Why hotel HVAC is its own discipline
Hotels are simultaneously the most demanding and the most heterogeneous building type a mechanical services engineer will design in a career. A 200-key urban luxury hotel is, in practice, eight buildings stacked on top of each other and operated continuously: a 200-room residential block, a 600-cover restaurant network, a 1,500-person ballroom, a 400 m² spa with steam and sauna, a 25 m lap pool, a 600 m² fitness centre, a casino floor in some assets, and 4,000 m² of back-of-house operations including a 24-hour kitchen, a 1,200 kg/day laundry, IT rack rooms, plant rooms and service corridors. Each of those eight buildings has different occupancy patterns, different ventilation rates, different acoustic criteria, different humidity loads, and different fire and smoke compartmentation requirements. Coordinating them into a single coherent HVAC system that meets brand standard, NABERS Hotels rating, AS 1668.2, ASHRAE 62.1, NFPA 96 and a dozen other codes is the art of hotel mechanical design.
Five characteristics make hotel HVAC fundamentally different from any other building type:
Twenty-four hour operation. Unlike an office tower that runs 12 hours a day five days a week, a hotel operates every minute of every day. The HVAC system never gets a maintenance window without affecting paying guests. This drives redundancy choices (N+1 on critical plant), failure-tolerant control strategies, sectional shutdowns by floor or zone, and ductwork access provisions that allow cleaning and inspection without entering occupied rooms.
Individual guest control expectation. Every guest expects to walk into their room, set the temperature to their preferred number on a dial or touchscreen, and have the HVAC respond within minutes. This drives the room-level fan coil unit (FCU) architecture that dominates hotel design above the budget tier, and the dedicated outdoor air system (DOAS) architecture that decouples ventilation from individual room temperature control.
Mixed-use density. A single hotel building might contain a guest room with NC-25 acoustic criteria sitting one floor below a 1,500-person ballroom that runs concerts until 2 AM. The HVAC system must service both spaces — quietly, with full fresh air, no cross-contamination of cooking smells from the kitchen below, and no leakage of bass frequencies through the supply duct. Ballroom AHUs are typically located in dedicated plant rooms with full acoustic isolation, and the ballroom supply ductwork passes through structural slabs sealed to brand-standard acoustic ratings.
Acoustic sensitivity. Hotel guest rooms are the most acoustically sensitive normally-occupied space type a HVAC designer specifies. AS/NZS 2107:2016 sets NC-30 as the maximum recommended in-room sound level; international five-star brand standards push this to NC-25, and presidential suites and signature villas often specify NC-20. Achieving these criteria reliably across hundreds of rooms requires internally lined supply duct (perforated metal facing over mineral wool), inline attenuators downstream of every fan coil, isolation hangers, low-velocity diffusers, and FCU selection at low fan speed. None of these is optional, and value-engineering them out of a project is the single most common cause of post-opening guest complaints.
Commercial kitchen integration. Hotels have multiple commercial kitchens — main hot kitchen, cold kitchen, pastry, banquet, room service, often a separate signature-restaurant kitchen and a staff cafeteria. Each requires Type I (grease) hood exhaust to NFPA 96, replacement air, and coordination with the building structure for riser routing. The grease duct is typically the single most contentious mechanical service on a hotel project — it has to be welded liquid-tight, sloped continuously back to the hood, separated from other services by 450 mm or fire-rated wrap, and must reach atmosphere via a continuous riser without horizontal offsets where grease can pool.
Premium guest expectation. Above all of this sits the expectation that a guest paying $800 a night for a Park Hyatt or Capella suite will not encounter HVAC. They will not hear it, smell it, see grilles in inappropriate places, feel cold drafts at the bed, or arrive in a room that is at the wrong temperature. The HVAC system is invisible when it works — and very visible when it does not. This drives the entire design philosophy of premium hotel HVAC: every visible element is detailed, every audible element is attenuated, every measurable parameter is tuned at commissioning to a tighter band than the brand standard requires.
Post-pandemic, a sixth characteristic has joined the list: infectious disease control. Major operators (Hilton, Marriott, Hyatt, Accor) have published cleanliness commitments that include enhanced filtration (typically MERV 13 minimum on guest floor return air), increased outdoor air rates above ASHRAE 62.1 minimum, UV-C irradiation in some applications, and demonstrable air change rates in public areas. The HVAC system documentation now needs to support an infection-control narrative that the operator's marketing team can use credibly with corporate accounts and high-end leisure guests.
Hotel categories and brand standards
Hotel HVAC specifications scale with brand tier. The same square metre of floor area receives a fundamentally different mechanical specification at a Park Hyatt versus a Quest serviced apartment, and an experienced hotel engineer reads the brand from the brief before reading the architectural drawings.
Five-star international
The five-star international segment includes the Hilton Curio and Conrad collections, Marriott's Ritz-Carlton, JW Marriott, St Regis and W brands, Hyatt's Park Hyatt and Andaz, the Four Seasons, Mandarin Oriental, Capella, IHG's InterContinental and Six Senses, and Australian-developed luxury such as Crown Hotels and Pier One Sydney. HVAC specifications in this tier typically include: NC-25 guest rooms, NC-20 in suites and presidential suites, four-pipe fan coil units, full DOAS with energy recovery, MERV 13 minimum filtration, internally lined supply ductwork to all guest rooms, dedicated AHUs per ballroom and signature restaurant, 316L stainless throughout the wellness and pool zones, and pre-opening acoustic verification with NC measurements in 10 percent of rooms. Brand standards are typically 200–400 pages of mechanical engineering specification overlaying SMACNA, ASHRAE 62.1 and ASHRAE 90.1 with project-specific tightening.
Four-star upper-upscale and business
The four-star upper-upscale segment includes Marriott (full-service Marriott Hotels), Sheraton, Hilton flagship, Hyatt Regency, IHG Crowne Plaza and Holiday Inn, and Accor's Pullman, Sofitel mid-range and select Novotel properties. HVAC specifications: NC-30 guest rooms, two- or four-pipe fan coil, DOAS with or without energy recovery (often value-engineered for energy recovery only on guest floors), MERV 11 to MERV 13 filtration, lined flexible duct standard for FCU connections, dedicated AHUs for ballroom and main F&B venues, 316L stainless in wet areas, and acoustic verification on commissioning samples rather than every room. Brand standards in this tier are typically 100–200 pages.
Three-star limited service
The three-star limited service segment includes Mantra, Adina, Travelodge, Vibe, Quest serviced apartments, Hyatt Place and Hyatt House, Holiday Inn Express, Hampton by Hilton, Best Western Premier and Mercure. HVAC specifications: NC-30 to NC-35 guest rooms, two-pipe fan coil with electric reheat or simple split systems, fresh air either through dedicated DOAS (better) or window infiltration plus bathroom exhaust (cheaper), MERV 8 to MERV 11 filtration, standard flexible duct connections, ballroom and meeting room consolidation rather than dedicated AHUs per space. Brand standards are usually 50–100 pages and reference the local code (NCC Section J, AS 1668.2) as the baseline rather than overlaying significant brand premiums.
Motel and budget
The budget segment includes Best Western Plus and Best Western, Comfort Inn, Days Inn, Travelodge International, Ibis Budget and Hotel Formule 1, Tune Hotels and traditional Australian motels. HVAC specifications: NC-35 guest rooms acceptable, packaged terminal air conditioners (PTAC) or window-wall units in many properties, no separate DOAS, basic bathroom exhaust to AS 1668.2 minimum, no acoustic verification beyond drop-by checks. Branded budget hotels still maintain code compliance and acceptable basic comfort, but they do not engage in brand-premium acoustic, IAQ or aesthetic specifications.
Serviced apartments and extended stay
The serviced apartment and extended stay segment includes Quest, Adina, Meriton Suites, Oaks, Mantra Apartments, Element by Westin and Hyatt House. HVAC specifications include in-room kitchen exhaust (different from a hotel guest room because guests cook) — typically Type II hood exhaust at 100–150 L/s per apartment, a fan coil for sensible cooling, fresh air either through DOAS or per-apartment energy recovery ventilator (ERV), and an apartment-level moisture management strategy because clothes drying and cooking add significant latent load. The duct distribution is more complex than a typical hotel because each apartment has a kitchen exhaust riser, bathroom exhaust riser, and a fresh air supply.
Boutique and luxury independents
Boutique and luxury independent operators in Australia include Ovolo Hotels, Pier One Sydney, QT Hotels, Adge Hotel, the Calile in Brisbane, Halcyon House, Spicers Retreats and the Como The Treasury in Perth. These properties are typically 50–200 keys, often in adaptive-reuse heritage buildings, with strong design narratives that drive the architectural and FF&E expression. HVAC specifications follow the corresponding brand tier (boutique luxury at five-star spec, boutique upscale at four-star) but with significant adaptation for the heritage building constraints — often VRF systems instead of central plant, in-ceiling concealed FCUs instead of below-window units, and acoustic challenges from existing structures that lack modern slab-to-slab partitions.
Australian hotel operators and their portfolios
The Australian hotel sector is dominated by a handful of large operators whose brand standards drive most of the new-build and refurbishment HVAC specification work in the country. Understanding each operator's preferences shortens the design cycle considerably.
Accor
Accor is the largest hotel operator in Australia by room count, operating Sofitel, Pullman, MGallery, Movenpick, Mantra, Peppers, Novotel, Mercure, ibis, ibis Styles and ibis Budget across more than 350 properties. Their luxury and upper-upscale brands (Sofitel, Pullman, MGallery) follow Accor's "Esprit Sofitel" and "Pullman Care" engineering standards which include full DOAS, NC-25 guest rooms in Sofitel, MERV 13 filtration, and Accor's Planet 21 sustainability programme that targets specific NABERS Hotels ratings. The mid-tier Novotel and Mercure standards are pragmatic — local code compliance plus targeted acoustic and IAQ premiums. The ibis brands follow lean budget mechanical specifications.
Crown Resorts
Crown Resorts operates three integrated resort hotels — Crown Casino Melbourne (1,604 rooms across Crown Towers, Crown Metropol and Crown Promenade), Crown Sydney at Barangaroo (349 rooms in the iconic Wilkinson Eyre tower opened 2020), and Crown Perth (around 1,200 rooms across three hotels). The Crown Sydney project at Barangaroo is the highest-specification hotel HVAC project completed in Australia in the past decade — six-star ambitions, NC-20 in signature suites, full-floor casino-tier ventilation in the high-roller gaming areas, four signature restaurants from chefs including Clare Smyth, and a 1,000 m² pool/spa complex on level 26. The Crown engineering standards are project-specific rather than a brand template, but consistently target the absolute upper end of Australian hotel HVAC quality.
TFE Hotels
TFE Hotels (Toga Far East Hotels) is an Australian-Singaporean operator running Adina Apartment Hotels, Travelodge, Vibe, Rendezvous, Quincy, A by Adina and TFE Hotels Collection across 70+ Australian and New Zealand properties. The Adina serviced-apartment brand is the largest of the group and drives most of TFE's mechanical engineering work — apartment-level kitchen exhaust, energy recovery ventilators, and four-pipe FCU on the upper-tier Adina properties.
Salter Brothers and Pro-invest
Salter Brothers and Pro-invest Group are the two largest Australian hotel investment platforms, between them owning more than $5 billion of Australian hotel real estate including a substantial Holiday Inn Express portfolio (Pro-invest) and a luxury and upscale portfolio that includes Mantra, Sebel and InterContinental properties (Salter Brothers). Their development pipelines drive significant new HVAC procurement work each year.
Event Hospitality and Entertainment
Event operates Rydges, QT Hotels, Atura and Independent Collection across 70+ Australian and New Zealand properties. The QT brand is a design-led upper-upscale segment with strong individual property identities — QT Sydney, QT Melbourne, QT Perth, QT Newcastle, QT Bondi, QT Auckland and QT Queenstown — each with project-specific mechanical specifications adapted to the architectural concept.
International operators in Australia
Hilton Australasia operates around 20 properties spanning Conrad, Hilton, DoubleTree, Hilton Garden Inn and Hampton. Marriott International runs nearly 40 Australian properties across Ritz-Carlton, JW Marriott, W Hotels, Westin, Sheraton, Marriott, Le Meridien, Element, Aloft, Four Points and Courtyard. IHG Australia operates InterContinental, Crowne Plaza, Holiday Inn, Holiday Inn Express, voco, Kimpton and Indigo across 50+ properties. Hyatt Australia runs Park Hyatt Sydney and Melbourne, Grand Hyatt Melbourne, Hyatt Regency Sydney, Andaz, and Hyatt Place properties. Each international operator imports their global brand engineering standards which tend to exceed local code substantially in the luxury and upper-upscale segments.
Major Australian hotel projects driving HVAC specification
The reference projects listed below are the benchmark hotel HVAC schemes against which new Australian hotel projects are typically benchmarked.
Crown Sydney at Barangaroo
Opened in December 2020 and designed by Wilkinson Eyre architects, Crown Sydney is a 75-storey hotel and apartment tower with 349 hotel keys and 82 luxury residences. The HVAC scheme includes: full DOAS with energy recovery on every guest floor, four-pipe fan coil units in every room, NC-20 in signature suites, dedicated AHUs for each of the four signature restaurants, a casino-floor ventilation scheme that handles peak gambling occupancy, a 25 m lap pool with 316L stainless ductwork throughout the pool hall, and a sky lounge on level 88 with high-velocity perimeter air management for the floor-to-ceiling glass. The project is widely considered the apex of Australian hotel HVAC.
W Sydney Darling Harbour
Opened in October 2024 and operated by Marriott as part of the W brand, W Sydney is a 595-key flagship across two interconnected towers at the Ribbon development, Darling Harbour. The HVAC scheme covers W's distinctive design-led acoustic and lighting integration, a 600-cover signature restaurant by chef Marc Polese, the W Living Room (lobby bar) at 800 m², a ballroom complex of 1,200 m² that subdivides into six junior ballrooms, a substantial AWAY Spa, and a rooftop pool deck with retractable glazing. The project showcases Marriott's W brand engineering standards adapted for high-density urban Australian construction.
Capella Sydney
Opened in March 2023, Capella Sydney is a 192-key luxury hotel in the heritage-listed Department of Education building at Bridge and Loftus Streets. The HVAC scheme is the most challenging type of hotel mechanical design — adaptive reuse of an early-20th-century sandstone heritage building with very limited shaft and slab penetrations available. The team specified VRF for guest rooms (no four-pipe central plant could be retrofitted), bespoke supply diffusers integrated into heritage cornice details, a ground-floor signature restaurant (Brasserie 1930) with carefully concealed kitchen exhaust routing, and a basement spa with mechanical ventilation that does not impact the heritage facade. Capella Sydney sets the benchmark for Australian heritage adaptive-reuse hotel HVAC.
Ritz-Carlton Melbourne
Opened in March 2023 and occupying the upper 16 floors of the 80-storey West Side Place tower in Melbourne's CBD, the Ritz-Carlton is a 257-key luxury flagship for Marriott in Melbourne. The HVAC scheme handles the high-rise stack effect in a slim residential-tower form factor, includes a sky-level pool and spa on level 80, a signature restaurant (Atria) on level 80, and lobby/check-in on level 80 — meaning every supply, return and outdoor air route runs vertically through a 250 m tower with associated stack-effect, fire and smoke management challenges.
Park Hyatt Sydney refurbishment
The Park Hyatt Sydney at the foot of the Sydney Harbour Bridge undertook a comprehensive refurbishment programme in stages from 2018 through 2023. The HVAC retrofit included full plant room renewal, replacement of the original 1990 four-pipe FCU system, integration of contemporary DOAS, upgrade of the rooftop pool dehumidification system to current 316L stainless duct specification, and acoustic re-tuning of guest rooms to achieve current Park Hyatt brand NC-25 criteria. The project is a textbook example of luxury hotel HVAC retrofit with rooms remaining in operation through phased shutdowns.
Tasmanian luxury resort programme
Tasmania has emerged in the past decade as Australia's most active luxury resort development market — properties include Saffire Freycinet (Coles Bay), the MACq 01 (Hobart), the Henry Jones Art Hotel (Hobart), the planned Pumphouse Point expansion, the Tasman (Hobart), and Spicers Retreats Tasmanian properties. These are typically 30–100 keys, low-rise, with substantial F&B and spa programmes. The HVAC scheme tends toward heat recovery ventilation appropriate to the Tasmanian cool-temperate climate, hydronic radiant in some lounges and spas, and bespoke architectural integration of supply diffusers in heritage and design-led buildings.
Cairns and Gold Coast resort upgrades
The Queensland resort segment is undergoing a substantial NABERS-driven upgrade programme. Properties including the Hilton Cairns, Pullman Reef Hotel Casino, Sheraton Grand Mirage Gold Coast, JW Marriott Gold Coast, the Star Gold Coast hotels, and the planned Mondrian Gold Coast all have substantial mechanical refurbishment work in pipeline. The Queensland tropical climate drives different HVAC priorities than southern Australia — humidity control is dominant, free cooling is rarely available, and pool hall and beachfront restaurant ventilation needs to handle salt-laden air in addition to chlorinated humidity.
Standards and codes
Australian hotel HVAC projects sit at the intersection of multiple overlapping regulatory frameworks. The mechanical engineer's first task on any project is to confirm which of the following apply and at what level.
Ventilation and indoor air quality
ASHRAE Standard 62.1-2022 — the international baseline for ventilation and indoor air quality. All international branded hotels reference 62.1 in their engineering standards. Key tables include 6-1 (minimum ventilation rates by space type), 5.6 (filtration), and 8.4 (system commissioning). Five-star brands typically specify outdoor air at 1.25 to 1.5 times the 62.1 minimum.
AS 1668.2-2012 — the Australian standard for mechanical ventilation in buildings. Applies to all Australian projects regardless of brand. Sets minimum outdoor air rates per AS 1668.2 Table 3.1 (e.g. 10 L/s per person for guest rooms, 6 L/s/m² for kitchens, 25 L/s/m² for pool halls in some configurations) and bathroom exhaust rates (typically 8–10 ACH for hotel ensuites).
Energy efficiency
ASHRAE 90.1-2022 — the international energy standard. Section 6 governs HVAC system efficiency, section 6.4 mandates ductwork insulation and seal class.
NCC Section J — the Australian National Construction Code energy efficiency provisions. Volume One (Class 5–9 buildings, which includes hotels) sets minimum building envelope, glazing, lighting, lift and HVAC efficiency requirements. Section J6 covers HVAC, J5 covers building sealing, J3 covers thermal performance of the envelope. Hotels above three storeys must comply with current NCC Section J at the date of building permit.
NABERS Hotels — the Australian rating tool specific to the hotel sector. NABERS Hotels rates whole-of-hotel performance per guest night and is the dominant sustainability rating tool for hotel commercial real estate in Australia. Most institutional hotel investors target a minimum 4 stars NABERS Hotels with a stretch target of 5 stars. The HVAC system is the single largest contributor to NABERS Hotels rating outcomes — duct leakage class, insulation, fan power, AHU efficiency and BMS metering all directly drive the rating.
Green Star Performance — the operating-rating product of the Green Building Council of Australia, used by some institutional owners as a complement or alternative to NABERS. Green Star addresses a broader set of sustainability dimensions than NABERS but is less hotel-specific.
Commercial cooking
NFPA 96 — the international standard for commercial cooking ventilation, referenced by virtually every international branded hotel as the kitchen exhaust baseline. Sets hood capture velocity, grease duct construction, fire protection, cleaning intervals, and access door requirements.
AS 1668.2 commercial cooking provisions — the Australian equivalent within AS 1668.2. Largely consistent with NFPA 96 but with some Australian-specific access door spacing and clearance requirements.
Acoustic performance
AS/NZS 2107:2016 — the Australian and New Zealand standard for recommended indoor sound levels. Table 1 sets the recommended NC range by space type: NC-25 to NC-35 for hotel guest rooms (depending on tier), NC-30 to NC-40 for hotel meeting rooms, NC-35 to NC-45 for hotel restaurants. International brand standards typically specify the lower (quieter) end of the AS/NZS 2107 range.
Fire and smoke management
AS 1668.1 — Australian fire and smoke management ductwork. Sets construction, leakage and integrity requirements for stair pressurisation, smoke spill, smoke exhaust and zone smoke control duct.
NFPA 92 — international atrium smoke management standard, referenced by international branded hotels with atrium designs.
AS 1530.4 — fire test method for service penetrations including duct fire dampers and fire-rated wraps.
Guest room HVAC architecture
Guest rooms typically account for 60–75 percent of conditioned floor area in a hotel, but they account for only 25–40 percent of HVAC plant capacity because the load is spread, intermittent and dominated by the simultaneous diversity of when guests are actually in their rooms. Designing guest room HVAC well is the single most important determinant of guest experience and the single largest determinant of operating energy cost.
Fan coil unit (FCU) configuration
The dominant guest room HVAC architecture across the upscale and luxury segments is the four-pipe fan coil unit. Each room has a recessed-ceiling or below-window FCU sized for room-peak sensible cooling and a coil that switches between chilled water and hot water depending on room thermostat call. Four-pipe gives simultaneous heating and cooling capability anywhere in the building, which matters in shoulder seasons when north-facing rooms call for cooling while south-facing rooms call for heating. Two-pipe systems (used in three-star and lower) only provide one mode at a time across the building or large zones, with electric reheat at the room level for the off-mode requirement.
Dedicated outdoor air system (DOAS)
Above the three-star tier, the FCU is paired with a dedicated outdoor air system (DOAS) that delivers tempered, dehumidified outdoor air directly to each room at room-neutral conditions (typically 18–22 °C and 8–10 g/kg moisture content). The DOAS handles the entire ventilation latent load and a portion of the sensible load, leaving the in-room FCU to handle only the residual sensible load and provide individual guest temperature control. This decoupled architecture has three major advantages over single-coil all-air designs: (1) significantly quieter rooms because the fresh air is delivered at low velocity through a separate small grille, (2) better indoor air quality because outdoor air rate is controlled at the system rather than dependent on room call, and (3) substantially lower energy because the FCU handles only the small residual sensible load while the larger DOAS handles ventilation efficiently with energy recovery.
Bathroom exhaust
Hotel bathrooms require dedicated continuous mechanical exhaust per AS 1668.2 — typically sized at 8–10 air changes per hour, which translates to 25–35 L/s on a typical hotel ensuite of 4–6 m². The exhaust riser runs vertically through the building to a roof fan, with backdraft dampers at each room outlet and constant-volume regulators to maintain flow regardless of stack effect. Premium five-star brand standards push bathroom exhaust to 12–15 ACH and add a humidity sensor that boosts exhaust to 25 L/s during shower use. The bathroom exhaust riser is the single tightest mechanical service in a hotel — it is the primary path for cross-room odour and particulate transfer if construction is not airtight.
Acoustic specification — achieving NC-25
NC-25 in a hotel guest room is the single most demanding acoustic specification in routine commercial mechanical engineering. Achieving it requires:
- FCU sound power selection — the FCU must be sized for low-speed operation at room-peak sensible load, with manufacturer NC ratings at low speed of NC-22 or quieter as the starting point
- Internally lined supply duct — supply duct from FCU to room diffuser is internally lined with mineral wool faced with perforated metal, providing 8–12 dB attenuation per metre of duct length at 250–500 Hz
- Inline attenuator — an inline rectangular attenuator immediately downstream of the FCU provides further 12–18 dB attenuation at the dominant FCU frequencies
- Low-velocity diffuser — supply diffusers selected for face velocity below 2 m/s and NC rating of NC-22 or quieter at design flow
- Isolation hangers — the FCU is suspended on spring or rubber isolation hangers to break the structure-borne path from fan vibration to ceiling drywall
- Bathroom exhaust isolation — the bathroom exhaust grille and riser must be acoustically separated from the bedroom by a closed bathroom door and lined transfer duct
Even with all of the above, achieving NC-25 reliably across hundreds of rooms requires acoustic verification at commissioning. Premium brands measure NC in a sample of 10 percent of rooms (typically 20 rooms in a 200-key hotel) using an octave-band sound level meter against the standard NC contour. Rooms above NC-25 are remediated by adjusting fan speed, replacing diffusers with quieter selections, or extending lined duct lengths.
For a deeper treatment of acoustic duct design see our acoustic HVAC duct lining and attenuator guide.
Lobby and atrium HVAC
The lobby is the guest's first impression of the hotel and the most-photographed space in the building. The HVAC scheme has to deliver thermal comfort at peak check-in occupancy, work invisibly within architectural feature ceilings, manage smoke for any space designated as an atrium, and avoid drafts at the front-door interface where outdoor air ingresses every time the door opens.
Lobby ventilation
Lobby ventilation rates per ASHRAE 62.1 are 5 cfm/person + 0.06 cfm/ft² (≈ 25 L/s + 0.3 L/s/m²). For a typical 800 m² hotel lobby with peak check-in occupancy of 100 people, this gives 2,500 + 240 = 2,740 L/s of outdoor air. The full lobby AHU sizing is typically 15,000–25,000 L/s including return air recirculation — the lobby is volumetrically large and the air change rate is typically 4–6 ACH at peak. Cooling load is dominated by solar gain through lobby glazing, lighting and occupancy heat. The supply diffuser strategy uses long-throw architectural slots, perimeter floor swirl diffusers in some designs, or low-velocity displacement ventilation in atrium configurations.
Atrium smoke management
Any atrium in a hotel — defined as a space connecting more than two storeys with an unenclosed opening — requires engineered smoke management per AS 1668.4 (Australia) or NFPA 92 (international). The system typically includes high-volume smoke exhaust fans at the atrium roof, makeup air at low level, and tight smoke duct construction (AS 1668.1 Class A leakage, fire-rated to the relevant resistance level). Atrium smoke management AHUs and fans are not the same plant as the comfort HVAC — they are dedicated emergency systems triggered by fire detection. The duct supplying the smoke exhaust system is welded or fully sealed to prevent smoke leakage into adjacent compartments during a fire, and is typically fire-rated for 2 hours where it passes through fire compartments.
For a deeper treatment of fire and smoke duct integration see our fire and smoke damper HVAC duct integration guide.
Restaurant and bar HVAC
Hotel F&B venues are simultaneously commercial restaurants and integrated parts of the hotel HVAC system. The combination drives a different design approach than a standalone restaurant.
Customer dining area
Dining area ventilation per ASHRAE 62.1 is 7.5 cfm/person + 0.18 cfm/ft² (≈ 38 L/s + 0.9 L/s/m²) — substantially higher than guest rooms because of higher CO₂ generation, higher latent load, and food and beverage odour management. NC criteria are NC-35 to NC-40 in fine dining, NC-40 to NC-45 in casual dining and lobby bar. The supply diffuser layout has to coordinate with the F&B operator's table layout and lighting design — tight integration with the architectural ceiling is mandatory in any signature restaurant.
Bar and cocktail lounge
Bar areas have higher air change rates than dining (typically 8–12 ACH versus 6–8 ACH) to manage spirit vapours and cigar smoke historically (now declining as smoking bans expand). The supply temperature is often 1–2 °C cooler than dining to compensate for lower air change rate as people stand at the bar. Acoustic criteria are deliberately higher than dining (NC-40 to NC-45) because background noise supports the social atmosphere of a bar.
Kitchen exhaust integration
The kitchen exhaust system is the most complex element of any hotel F&B HVAC scheme. Per NFPA 96 (or AS 1668.2 commercial cooking section):
- Hood capture velocity — 80 fpm (0.4 m/s) for medium-duty cooking (steam, light wok), 100 fpm (0.5 m/s) for typical hotel main-line cooking, 125 fpm (0.65 m/s) for high-temperature wok and char-broiler
- Grease duct construction — 16-gauge (1.6 mm) black steel minimum, continuously welded liquid-tight, no internal lining or insulation that could trap grease, sloped 1:50 minimum back to the hood
- Access doors — every 3.5 m of horizontal duct and at every change of direction, with grease-tight gaskets
- Fire suppression — wet chemical (Ansul or equivalent) at the hood, automatic fan shutdown on fire signal
- Replacement air — 70–90 percent of exhaust volume supplied by a dedicated MUA unit, with the balance supplied to the dining area to keep the kitchen at slight negative pressure
- Riser routing — continuous vertical riser to roof discharge, no horizontal offsets where grease can pool, separated from other building services by 450 mm clearance or fire-rated wrap
The grease duct must be specified, fabricated, installed, sealed and tested as a single welded system. SBKJ does not supply grease ducts on auto duct lines — grease ducts are field-welded from 16-gauge black steel sheet. SBKJ machinery serves the kitchen replacement air, dining area supply, and bar supply duct in galvanised steel.
Ballroom and event space HVAC
The ballroom is the most variable load in the hotel — empty 80 percent of the time, full house 5 percent of the time, with the remaining 15 percent of time at moderate occupancy for medium-sized events. Designing for the full-house peak while operating efficiently at empty is the central challenge.
Peak occupancy
Hotel ballroom occupancy varies dramatically with event type:
- Cocktail reception standing — 1.0 person/m² (a 1,000 m² ballroom holds 1,000 people)
- Banquet seated 12-person rounds — 0.7 person/m² (700 people in 1,000 m²)
- Theatre seating — 1.4 person/m² (1,400 people in 1,000 m²) — the highest density
- Classroom seating — 0.5 person/m² (500 people in 1,000 m²)
- Concert / cabaret — 1.2 person/m² (1,200 people in 1,000 m²)
The HVAC system must handle the highest of these densities, which is typically theatre seating. A 1,000 m² grand ballroom at theatre seating with 1,400 occupants generates approximately 175 kW of sensible heat and 30 kg/h of moisture. The supply air volume to handle this load at a 12 °C supply-room delta is approximately 50,000 L/s — a large, dedicated AHU that sees full duty perhaps 50 hours per year.
Demand-controlled ventilation
Demand-controlled ventilation (DCV) using CO₂ sensors lets the BMS modulate outdoor air between empty and full house. The CO₂ setpoint is typically 800 ppm (versus 400 ppm outdoor), with the AHU outdoor air damper modulating from minimum 10 percent at empty to 100 percent at peak. DCV saves 60–80 percent of ventilation energy on the average operating day and is the single largest individual energy saving available in hotel HVAC.
Operable partition coordination
Most hotel ballrooms can subdivide into 2–6 smaller event rooms via operable partition walls. The HVAC zoning has to align with the partition wall lines so each sub-divided room has an independent thermostat, independent CO₂ sensor, and independent outdoor air control. Acoustic separation between partition-divided rooms requires careful coordination of supply ductwork — a single supply branch crossing the partition line carries sound between rooms even when the partition is closed. The standard solution is independent supply branches per sub-room, with each branch lined for 3 m upstream of the diffuser and an inline attenuator at the AHU.
Pool and spa HVAC
Hotel pools and spas require fundamentally different ductwork from any other hotel space. Chlorine in a humid environment is corrosive to galvanised steel — galvanised duct in a pool hall corrodes through within months. The standard specification for all duct exposed to pool atmosphere is 316L stainless steel, with EPDM gaskets rated for chlorine.
For a complete treatment of pool HVAC including dehumidifier sizing, vapour barrier integration, condensation control and pool water chemistry, see our indoor pool and aquatic centre HVAC duct guide. The key points specific to hotel pools are:
- 316L stainless throughout — supply, return, exhaust, and any duct passing through the pool hall plenum or service voids carrying pool air
- Dehumidifier sizing — typical hotel pool of 25 m by 12 m generates 80–120 kg/h of moisture at design conditions, requiring a 30–50 kW dehumidification load
- Heat recovery from pool exhaust — the pool exhaust air is hot and humid, making it an ideal source for energy recovery to preheat outdoor air or pool water
- Integration with hotel guest experience — pool decks are guest amenity spaces with NC-35 acoustic criteria, requiring lined supply ductwork in stainless that adds cost versus standard galvanised lined
- Pool door and glazing detail — the pool envelope must be vapour-tight, and the HVAC scheme must keep the pool hall at slight negative pressure to the surrounding hotel to prevent humid air migration into adjacent guest rooms or lobby
Gym and fitness centre HVAC
Hotel gyms have the highest per-person ventilation requirement of any normally-occupied hotel space. ASHRAE 62.1 sets gym ventilation at 20 cfm/person + 0.06 cfm/ft² (≈ 100 L/s + 0.3 L/s/m²) — four times the rate of a typical guest room and twice the rate of a meeting room. The high rate handles the elevated CO₂ and moisture generation from exercising occupants.
Beyond the high outdoor air rate, hotel gym HVAC requires:
- Higher air change rate — typically 8–12 ACH for elevated odour and moisture management
- Lower temperature setpoint — typically 20–22 °C (versus 22–24 °C in the rest of the hotel) to compensate for high metabolic rates
- Anti-microbial filtration — many five-star brand standards specify MERV 13 with optional UV-C irradiation in the AHU to address gym-equipment-related bioaerosols
- Acoustic isolation — gym free-weight drops generate impact noise that travels through the slab to rooms above. The HVAC scheme should not exacerbate this — supply diffusers in flexible-mount frames isolated from the structural slab
- Locker and shower exhaust — locker rooms get 6–10 ACH exhaust, shower rooms get 8–12 ACH, both per AS 1668.2
Conference and meeting room HVAC
Hotel meeting rooms are the second-most acoustically sensitive space type after guest rooms. Business guests using a meeting room expect to be able to hear a softly-spoken voice at the far end of the room without HVAC interfering. NC-25 to NC-30 is standard, with NC-25 in boardrooms and presentation rooms.
Each meeting room above 25 m² gets a dedicated VAV terminal with CO₂ sensor and thermostat for occupant control. The VAV terminal allows demand-controlled ventilation — minimum outdoor air at empty room, full design air at peak occupancy — and individual temperature control independent of the central AHU. Operable wall partitions must align with VAV zone boundaries.
Acoustic spec — internally lined supply duct from VAV to room diffuser, inline attenuator at the VAV outlet, low-velocity slot diffusers integrated into the architectural ceiling, lined return path with sound traps before reaching the central return riser. Meeting rooms above 50 m² often get separate supply and return paths to minimise cross-talk between adjacent rooms via shared return plenums.
Spa and wellness HVAC
Hotel spa zones have multiple sub-environments with different HVAC requirements:
Steam room
Steam rooms operate at 40–45 °C and 100 percent RH, with a sealed waterproof construction. The HVAC scheme is a small dedicated steam generator (electric or gas) with no general ventilation — the steam room is essentially a closed humidity-saturated environment. Exhaust on door opening prevents pressure buildup. Materials in any duct exposed to steam atmosphere are 316L stainless throughout.
Sauna
Saunas operate at 80–95 °C and low humidity. The HVAC scheme provides a small fresh air intake near the heater, exhaust at the upper level, and a wood lining that absorbs and releases moisture passively. No general HVAC duct passes through a sauna.
Treatment rooms
Treatment rooms are the largest part of the spa programme by floor area. Each room typically has individual thermostat control, 6–8 ACH ventilation, and a relatively low NC criterion (NC-30) for the relaxation atmosphere. Aromatherapy oils are common — the exhaust must be at a sufficient rate to clear oils between treatments, and the AHU return path should not recirculate treatment-room exhaust to other spa zones.
Vichy and hydrotherapy rooms
Vichy showers and hydrotherapy rooms are small wet zones with high latent load. Local exhaust at 15–20 ACH plus a heated supply air to manage condensation. Floor drains are essential. Materials in supply and exhaust duct are 316L stainless within the wet zone.
Salt rooms and float tanks
Salt rooms (Halotherapy chambers) and sensory deprivation float tanks are highly specialist installations supplied by specialist vendors. The hotel HVAC integration is typically a low-rate fresh air supply and an exhaust to manage door-opening transfer. The vendor sets the room-internal HVAC.
Casino HVAC
Hotels with integrated casinos (Crown Sydney, Crown Melbourne, Crown Perth, the Star Sydney, the Star Gold Coast, the Star Brisbane Queens Wharf, Reef Hotel Casino Cairns) have casino-specific HVAC requirements that exceed general hotel standards.
Peak occupancy
Casino floors can run at high density — particularly during peak gambling periods, special events, and concerts in adjacent venues. A 5,000 m² casino floor at peak can hold 2,500–3,500 people. The HVAC scheme must handle this peak with full outdoor air rates per ASHRAE 62.1 (5 + 0.06 for general gambling area, higher for concentrated gaming tables).
Historic smoking permit areas
Australian state laws have progressively banned smoking in casinos — Victoria from 2010, NSW substantially restricted, Queensland and WA progressively tightening. The remaining permit areas are typically high-roller rooms with separate dedicated exhaust and sealed smoking rooms with up to 25 ACH. Where smoking is permitted, the HVAC scheme requires:
- Sealed envelope with negative pressure to surrounding casino floor
- Dedicated exhaust riser direct to roof, no recirculation to general HVAC
- Smoke filtration on the makeup air for the smoking-permitted zone (typically activated carbon)
- High air change rate (15–25 ACH) to manage tar and nicotine deposit on surfaces
Casino HVAC duct in non-smoking areas is standard galvanised; in smoking-permit areas it is typically 304L stainless to manage tar deposition that compromises galvanised duct.
Back-of-house HVAC
BOH services occupy 30–40 percent of hotel floor area and are the workhorse of the operation. The HVAC scheme covers:
Laundry
Hotel laundries (where the laundry is on-premises rather than outsourced) generate substantial heat and moisture. A 200-key hotel typical on-premises laundry processes 1,000–1,500 kg/day of linens, generating 30–50 kW of sensible heat and 5–10 kg/h of moisture from drying. Exhaust requirements per AS 1668.2 are 6–10 ACH for the general laundry plus dedicated dryer exhaust direct to atmosphere. The laundry exhaust riser is separated from grease exhaust and from general building HVAC — laundry steam and lint are corrosive and must not migrate to other zones.
Housekeeping storage
Housekeeping storage rooms hold cleaning chemicals (chlorine bleach, ammonia, surfactants) and require chemical exhaust at 4–6 ACH continuous. The exhaust path is direct to atmosphere with no recirculation. Storage room finishes are chemical-resistant (epoxy floor, tiled walls).
IT rack rooms
Hotel IT rack rooms house the property management system, the BMS server, the security and CCTV recorders, and the network core. Cooling load is 5–25 kW depending on hotel size. The HVAC scheme is a dedicated chilled water FCU at 22 °C setpoint with N+1 redundancy (two FCUs each sized for full load), continuous 24/7 operation, BMS-monitored, with a high-temperature alarm escalating to engineering supervisor on call. Smoke detection in the rack room is dual-stage (VESDA aspirating plus standard ceiling smoke detectors). The rack room HVAC is independent of the general hotel HVAC — the IT system must keep running even when the main plant is shut down for maintenance.
Kitchen back-of-house
Kitchen back areas (cold rooms, dry stores, prep areas, dishwash, garbage rooms) have specific exhaust requirements per AS 1668.2 — typically 6–10 ACH for prep areas, dedicated cold room HVAC (cold rooms are refrigeration not HVAC, but the corridor outside the cold room often gets ducted exhaust), 12–15 ACH for dishwash and pot wash to manage steam, 8–12 ACH for garbage and waste rooms with dedicated exhaust to atmosphere.
Service corridors
Service corridors connect back-of-house functions and run alongside guest corridors on guest floors. The HVAC scheme keeps service corridors at slight positive pressure to back-of-house service rooms (so odours stay in the rooms) and slight negative pressure to guest corridors (so service smells do not migrate to guest areas). Air change rate is 4–6 ACH.
Staff dining and locker rooms
Staff dining rooms (often called "the canteen" in hotel jargon) have a small commercial kitchen of their own, with dedicated grease exhaust at NFPA 96 standard. Staff lockers and changing rooms get 6–10 ACH per AS 1668.2. The staff toilet and shower facility gets 8–10 ACH per AS 1668.2 ensuite specifications.
Materials specification
Hotel duct material selection follows the space type and the air conditions. The standard specification for an Australian luxury hotel project is:
Galvanised G90 (Z275) for general HVAC
Galvanised steel sheet at G90 (Z275) zinc coating thickness is the workhorse of hotel HVAC — used for guest floor supply and return, lobby and atrium supply and return, ballroom and meeting room supply and return, conference room supply and return, and non-grease BOH ductwork. G90 (Z275) provides 30–50 year service life in conditioned indoor air. Lower zinc coatings (G60 / Z180) are not recommended for hotel projects because of the longer service life expectation and the brand cost of replacement.
Internally lined duct for guest room and conference acoustic
Guest room supply duct, conference room supply duct and any duct upstream of an NC-25 or NC-30 space gets internal acoustic lining. The lining is mineral wool at 25–50 mm thickness with a perforated metal facing to prevent fibre erosion into the airstream. Lined duct provides 8–12 dB attenuation per metre of duct length at the dominant FCU frequencies (250–500 Hz). The lined duct is fabricated on the SBKJ auto duct line with the lining installed inline before transverse joint forming, which keeps the lining flush with the duct interior and eliminates the field-installation labour of retrofitting lining to a finished duct.
304L and 316L stainless
304L stainless is used in kitchen non-grease exhaust (steam and condensate exhaust from dishwash, grease-free hood exhaust above pastry stations) and in some smoking-permit casino exhausts. 316L stainless is used for all pool, spa and steam room ductwork. The grade is selected for chloride resistance — 316L contains 2–3 percent molybdenum which dramatically improves pitting resistance in chlorinated atmosphere versus 304L.
Black steel for grease exhaust
Grease exhaust ductwork is 16-gauge (1.6 mm) black carbon steel with continuously welded liquid-tight seams. Galvanised, stainless and aluminised steel are not acceptable for grease exhaust per NFPA 96 because they are not field-weldable to the required standard. The grease duct is field-fabricated by the kitchen exhaust contractor — SBKJ machinery serves the makeup air, replacement air and dining area HVAC duct in galvanised, but does not produce grease ducts.
Fabric duct (Durkeesox / Prihoda)
Fabric duct is increasingly specified in some atriums and ballrooms as an architectural feature and a low-cost long-throw distribution method. Fabric duct hangs from a steel skeleton, is supplied via a single feed connection from a galvanised hard-duct main, and distributes air through perforated holes or fabric porosity along its length. Hotel applications of fabric duct are typically the great room of an event venue, an atrium ceiling, or a high-volume kitchen makeup air distribution. Fabric duct is washable (specifically designed for laundering) and meets fire codes when specified to the appropriate fire-rating class.
Acoustic specification by space
The full acoustic specification matrix for a typical Australian luxury hotel project is summarised below. Brand standards may tighten any individual line.
- Presidential suite, signature villa — NC-20 (the absolute upper bound of acoustic specification)
- Executive suite, premium guest room — NC-25
- Standard guest room (luxury and upper-upscale) — NC-25 to NC-30
- Standard guest room (upscale and midscale) — NC-30
- Boardroom, executive meeting room — NC-25 to NC-30
- Standard meeting room — NC-30 to NC-35
- Ballroom (concert and presentation events) — NC-30
- Ballroom (banquet and reception events) — NC-30 to NC-35
- Spa treatment room — NC-25 to NC-30
- Spa relaxation lounge — NC-25
- Lobby and reception — NC-35
- Lobby bar and cocktail lounge — NC-35 to NC-40
- All-day dining restaurant — NC-35 to NC-40
- Signature fine-dining restaurant — NC-30 to NC-35
- Casual restaurant and bar — NC-40
- Pool deck — NC-35
- Fitness centre — NC-40 to NC-45
- Casino general gaming floor — NC-45 to NC-50 (intentional masking of background noise)
- Casino high-roller room — NC-35 to NC-40
- Back-of-house corridor — NC-40 to NC-45
- Kitchen and BOH service area — NC-45 to NC-50
Construction phasing for hotels
A typical 200-key Australian hotel project has a 12–14 month construction programme on top of 6–9 months of design and approvals. The HVAC ductwork procurement and installation phasing typically follows this sequence:
Months 1–3 — Shell and core
Concrete structure, primary plant rooms, riser shafts. No ductwork installation yet but riser sleeve coordination and slab penetration sleeves are critical and irreversible if missed.
Months 4–6 — Risers and BOH
Major HVAC risers installed up the building including supply, return, exhaust, smoke management, kitchen exhaust, laundry exhaust, and bathroom exhaust risers. BOH ductwork installation in plant rooms, basement, ground floor service areas. Total ductwork volume in this phase: approximately 25–35 percent of project total.
Months 7–9 — Public area fitout (lower zones)
Lobby, ballroom, conference rooms, signature restaurant, lobby bar, spa, gym fitout. Public area ductwork including lined supply duct to high-acoustic spaces. Total ductwork volume: approximately 30–35 percent of project total.
Months 9–11 — Guest floor fitout
Guest room rough-in including FCU installation, bathroom exhaust connection, lined supply duct from FCU to bedroom and bathroom diffusers, DOAS supply branch to each room. Guest floor work is the largest ductwork volume by linear metre but each individual room is small — pre-fabricated guest room duct kits are standard practice on rooms-block construction above 100 keys. Total ductwork volume: approximately 25–30 percent of project total.
Months 10–12 — Pool, spa, kitchen finals
316L stainless ductwork in pool, spa and steam rooms. Kitchen grease exhaust welded and pressure tested. Pool dehumidifier commissioning. Pool envelope vapour barrier final close-out.
Months 12–14 — Pre-opening commissioning
Air balancing across the entire building — typically 8,000–15,000 individual measurement points on a 200-key luxury hotel. Leakage testing on smoke management duct. Fire damper drop testing. NC measurement in 10 percent of guest rooms. Kitchen exhaust capture velocity verification at every hood. Pool dehumidifier performance verification at design conditions. BMS point validation against I/O list. Full commissioning manuals and as-built CAD packages — typically 2,000–4,000 pages on a 200-key hotel.
Pre-opening commissioning is the single most schedule-critical phase of the project. Issues found here are 10x cheaper to fix than post-opening, and pre-opening commissioning failures regularly delay hotel opening by 2–8 weeks at significant commercial cost — a 200-key luxury hotel running at $400/key/night ADR loses $80,000 per night of delayed opening. The HVAC contractor's commissioning programme is therefore aligned with the hotel operator's pre-opening calendar including staff training, soft launch, friends-and-family stays, and grand opening.
Hotel retrofit market
The Australian hotel retrofit market is the second-largest source of HVAC ductwork demand after new build. Existing 1980s-90s hotels are being retrofitted for energy compliance (NCC Section J / NABERS Hotels), acoustic upgrade (premium guest experience), brand refresh (operator changes), and guest room reconfiguration (key counts and room mix changes). Major Australian retrofit projects in recent years include:
- Park Hyatt Sydney — staged refurbishment 2018–2023, full plant room renewal and DOAS retrofit
- InterContinental Sydney — multi-year refurbishment of the heritage Treasury building, mechanical upgrades coordinated with heritage constraints
- Sheraton Grand Sydney Hyde Park — guest floor refurbishment with FCU replacement and acoustic upgrade to current Marriott brand standard
- The Langham Melbourne — full HVAC refresh including DOAS retrofit and pool dehumidification upgrade
- Hilton Sydney — staged refurbishment with energy upgrades targeting NABERS Hotels improvement
- Sofitel Sydney Wentworth — full mechanical refresh ahead of brand recommitment
Retrofit projects have unique HVAC challenges: existing structure constrains shaft and slab penetration locations, asbestos-era buildings (pre-1990) require careful demolition coordination, hotel rooms remain in operation through phased shutdowns reducing daily working hours, and existing ductwork material may not be compatible with new specifications (e.g. existing pool hall galvanised duct must be replaced with 316L stainless). The retrofit ductwork specification is identical to new build, but the procurement quantities are smaller per phase, the lead times are shorter, and the contractor margin pressure is higher because of programme complexity.
SBKJ machinery for hotel projects
SBKJ supplies the duct manufacturing machinery used by HVAC fabricators serving hotel projects across Australia and internationally. The four machines below cover essentially the entire ductwork fabrication scope of a hotel project, with the exception of grease ducts (field-welded black steel, not produced on auto duct lines).
SBAL-V auto duct line — the workhorse
The SBAL-V auto duct line is the workhorse of hotel HVAC fabrication. A single SBAL-V outputs 60 m²/hour of rectangular galvanised duct with TDF transverse joint, and a 200-key hotel project typically requires 35,000–55,000 m² of galvanised rectangular duct supplied over a 12-month construction programme. One SBAL-V on single shift comfortably outputs the volume for one 200-key project at a time, with capacity headroom for parallel smaller projects. The SBAL-V handles coil widths up to 1,550 mm and thicknesses 0.5 to 1.5 mm — covering the full hotel HVAC gauge range from supply duct to fire-rated smoke duct. The line includes integrated TDF flange forming, beading, integral lining option (optional inline mineral wool installation for acoustic duct), and final cutoff. See the auto duct lines category for full SBAL-V specifications.
SBTF spiral tubeformer for round duct
The SBTF spiral tubeformer produces round galvanised duct in diameters from 100 to 1,500 mm for lobby, atrium, BOH service corridor, and pool/spa applications (in stainless versions). Round duct is more efficient than rectangular for the same air volume, has higher structural rigidity, and is the preferred geometry in exposed-feature applications such as design-led hotel atriums. The SBTF outputs at typical 5–8 m/min depending on diameter and gauge. See the spiral tubeformer category for full SBTF specifications.
TDF flange former for low-leakage smoke duct
The TDF flange former (integrated into the SBAL-V or available as a standalone) produces tight-leakage duct suitable for AS 1668.1 Class A smoke management duct and SMACNA Seal Class A. Smoke management duct in hotels — atrium smoke exhaust, stair pressurisation, zone smoke control — must be tight to prevent smoke leakage between fire compartments. TDF flange duct with butyl gasket strip achieves Class A leakage in mass production at the same throughput as standard galvanised duct.
Lined duct fabrication for guest room acoustic
Internally lined duct for guest room and conference acoustic supply is fabricated on the SBAL-V with the optional inline lining station. Mineral wool sheet (25 mm or 50 mm thickness) is fed into the line ahead of the transverse joint forming station, the wool is faced with perforated metal sheet at 25 percent open area, and the final lined assembly emerges as a complete rectangular lined duct in a single pass. This eliminates the field labour of retrofitting lining into finished duct — a significant cost saving on hotel projects with thousands of metres of lined supply duct.
How SBKJ supports hotel project teams
SBKJ Group works directly with HVAC fabricators serving the Australian hotel sector, including fabricators supplying the major operator portfolios (Accor, Hilton, Marriott, Hyatt, IHG) and the integrated resorts (Crown, the Star). Our engineering team supports project teams in three ways:
- Duct line sizing — given a hotel project programme (key count, m² of duct, construction duration), we size the SBAL-V configuration that matches the throughput requirement with sensible utilisation. A 200-key luxury hotel needs one SBAL-V on single shift; a 600-key integrated resort like W Sydney needs two SBAL-V on single shift or one on double shift
- Material specification matching — our standard auto duct line handles 0.5 to 1.5 mm galvanised G90/Z275. For 316L stainless pool and spa duct we configure tooling for stainless stock; for 16-gauge black steel grease ducts, we point to specialist welded-pipe suppliers because grease ducts are not auto-line products
- Acoustic duct optimisation — we specify the inline lining station for fabricators serving the luxury hotel segment where lined duct volume justifies the in-line lining capability versus field lining
SBKJ Group is based in Box Hill North, Victoria, and has supplied HVAC duct machinery to fabricators operating across the Australian eastern seaboard (NSW, Victoria, Queensland), Western Australia, and South Australia. Our after-sales engineering is provided in English from the Melbourne office with on-site visit capability for major projects. See SBKJ in Australia for our local presence and case studies.
Frequently asked questions
What NC criteria should hotel guest rooms be designed to?
AS/NZS 2107:2016 recommends NC-30 for typical hotel rooms and NC-25 for premium and five-star rooms. International luxury brands typically specify NC-25 with NC-20 in suites. Achieving NC-25 reliably requires internally lined supply duct, an inline attenuator, isolation hangers, and FCU selection at low fan speed. NC-30 is achievable with lined flex duct and standard FCU selection. Below NC-25 you typically need a dedicated outdoor air system plus a sound-isolated FCU located outside the guest room.
How does kitchen exhaust integrate with hotel HVAC?
Commercial kitchen exhaust in hotels follows NFPA 96 or AS 1668.2 commercial cooking. Hood capture velocity 80–125 fpm, 16-gauge black steel grease duct with continuously welded liquid-tight seams, no internal lining, sloped 1:50 minimum back to the hood, access doors every 3.5 m. Replacement air at 70–90 percent of exhaust through dedicated MUA. Grease duct must be separated from other ducts by 450 mm or fire-rated wrap. The hotel HVAC designer coordinates the kitchen exhaust risers with the architectural shafts at schematic stage.
What duct material is required for hotel pools and spas?
316L stainless throughout for all duct exposed to pool atmosphere — supply, return, exhaust and any duct passing through the pool plenum. 304L is acceptable in low-humidity zones. Galvanised steel corrodes in months in chlorinated environment and is not acceptable. Bolted flange joints with EPDM gaskets rated for chlorine. See the indoor pool HVAC guide for the full materials matrix.
What is the typical lead time for hotel ductwork supply?
For a 200-key Australian hotel with a 12–14 month construction programme, ductwork supply is staged: shell-and-core risers and BOH at month 4–6, public area at month 8–10, guest room kits at month 9–11, kitchen and pool stainless at month 10–12. Total volume is typically 35,000–55,000 m² of sheet metal duct plus 8,000–15,000 m of round and oval duct. One SBAL-V on single shift comfortably supplies a 200-key project.
How does ductwork support a NABERS Hotels rating?
Three ways: (1) low leakage construction — TDF flange duct sealed to AS 4254 Class A reduces fan power by 8–15 percent, (2) thermal insulation thickness — Section J sets minimum R-values that translate to NABERS energy performance, (3) zone control — VAV terminals on guest floor risers allow the BMS to throttle ventilation to unoccupied rooms, the single largest energy saving in hotel HVAC. SBKJ supplies low-leakage TDF and Mez-flange duct as standard on the SBAL-V line.
What ASHRAE 62.1 minimum air rates apply to hotel spaces?
Guest rooms 5 cfm/person + 0.06 cfm/ft² (≈ 25 L/s + 0.3 L/s/m²), lobby same, conference same, ballroom 5 + 0.06 at full occupancy, restaurant 7.5 + 0.18, bar 7.5 + 0.18, fitness 20 + 0.06, kitchen 7.5 + 0.12 with separate cooking exhaust, spa 5 + 0.06, pool deck 0.48 cfm/ft² (≈ 2.4 L/s/m²) of pool surface. AS 1668.2 sets equivalent Australian values; design to the more stringent of the two for international branded hotels.
What duct standard applies to hotel projects in Australia?
AS 4254.1 (rectangular) and AS 4254.2 (round) for general HVAC, AS 1668.1 for fire and smoke duct, AS 1668.2 for ventilation, NCC Section J for energy. International branded hotels overlay their own standards which typically reference SMACNA HVAC Duct Construction with project-specific tightening on leakage, gauge and acoustic. SBKJ machines produce duct compliant with both AS 4254 and SMACNA out of the box.
What are the typical occupancy peaks for hotel ballrooms?
Cocktail reception 1.0 person/m² (highest standing density), banquet seated 0.7 person/m², theatre seating 1.4 person/m² (highest density of all), classroom 0.5 person/m². A 1,000 m² ballroom at theatre seating reaches 1,400 occupants. Demand-controlled ventilation via CO₂ sensors saves 60–80 percent of ventilation energy on the average operating day. Supply duct sizing must still handle peak — typical 1,000 m² ballroom AHU is 35,000–55,000 L/s with 8–12 supply diffusers.
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