Why data centre HVAC duct is a different market
Hyperscale data centres are the single largest commercial HVAC project category in 2026. A 50 MW hyperscale facility consumes 8,000–15,000 m² of HVAC ductwork over a 12–18 month construction window, with strict tolerances on tolerance, fire rating and acoustic performance. The fabricators serving this market need a different equipment fleet, a different standards capability, and a different production rhythm than fabricators serving commercial office buildings or shopping centres.
SBKJ has supplied auto duct lines and spiral tubeformers to HVAC fabricators serving data centre projects in five regions over the past decade. The patterns repeat — once a fabricator wins a data centre framework agreement, the volume and the technical specification both step-change. This guide is the equipment and process framework we walk through with fabricators positioning for data centre work.
Airflow demand drives everything
Data centre cooling is sized by IT load. A typical 1 MW IT load requires approximately 75,000–110,000 CFM (35–50 m³/s) of cooling air at the ASHRAE TC 9.9 recommended supply temperature of 18–27 °C. Air handling units (CRAC/CRAH or air-side economiser) deliver this air through supply ductwork to the cold aisle, the hot return air is captured (often via hot aisle containment) and ducted back to the AHU.
For a 50 MW facility, that is 3.75–5.5 million CFM (1,750–2,600 m³/s) circulating continuously. The supply duct main risers are typically very large rectangular sections (1,500 × 750 mm or larger) running at +1 to +2 in.wg. Branch ducts step down to 600 × 400 mm and below. Round duct (spiral) is common for shorter runs and economiser intakes.
Standards that apply
- SMACNA HVAC Duct Construction Standards (rectangular and round) — dominant specification for data centre HVAC duct in North America, Middle East and international hyperscale projects. See our international standards comparison.
- EN 1505 / EN 1506 — Europe
- AS/NZS 4254.1 and 4254.2 — Australia and New Zealand (mandatory by NCC)
- ASHRAE 90.1 energy standard
- ASHRAE 62.1 ventilation standard
- ASHRAE TC 9.9 Thermal Guidelines — driving supply air temperature and humidity envelope
- UL 1978 / EN 1366-1 / BS 476 — fire-rated duct construction for risers and floor penetrations
- NFPA 75 / NFPA 76 — Standard for the Fire Protection of Information Technology Equipment (NFPA 75) and Fire Protection of Telecommunications Facilities (NFPA 76)
- Project-specific specifications — hyperscale operators (AWS, Azure, Google, Meta, Equinix, Digital Realty) often have additional brand-specific HVAC duct specifications layered on top of public standards
Gauge tables for data centre duct
Data centre supply air typically operates at +1 to +2 in.wg (250–500 Pa). Per SMACNA tables, this drives the following gauge:
- Up to 300 mm wide: 24-gauge (0.7 mm) galvanised
- 300–600 mm wide: 22-gauge (0.85 mm)
- 600–1,200 mm wide: 20-gauge (1.0 mm)
- 1,200–1,500 mm wide: 18-gauge (1.2 mm)
- Above 1,500 mm wide: 16-gauge (1.5 mm) with reinforced cross-bracing
Hot aisle return duct often operates at slight negative pressure (-1 to -3 in.wg in containment systems) and follows the negative-pressure SMACNA tables, typically requiring one gauge heavier than the supply for equivalent dimension. Reinforcement spacing tightens for negative pressure applications.
Fire-rated duct in data centres
Data centre HVAC duct frequently passes through fire-rated walls (compartmentation walls, generator room separations) and floor penetrations. These passages require fire-rated duct construction per:
- UL 1978 in North America (1-hour or 2-hour fire rating)
- EN 1366-1 in Europe (E, EI 30, EI 60, EI 90, EI 120 ratings)
- BS 476 Part 24 in the UK
- AS 1530.4 in Australia
Typical fire-rated construction: standard galvanised duct wrapped with fire-rated insulation board (Promat 25 or 50 mm board, Cafco K150 spray, or 3M Interam wrap) at fire-rated penetrations. The duct manufacturing shop produces the steel duct using standard SBAL-V or spiral tubeformer; the fire wrap is applied on site by the HVAC fitter. SBKJ supplies the duct forming equipment; we do not supply the fire wrap material.
Acoustic performance
Data centre supply duct often runs adjacent to office spaces, NOC rooms or building occupied areas. Acoustic transmission through duct walls is typically managed by internal duct lining (1" or 2" foam-faced fibreglass internal duct liner). For very high acoustic requirements, double-skin acoustic duct with mineral fibre infill is specified. SBAL-V can be configured to produce double-skin duct with internal liner; the second-skin closure is performed at the rectangular forming station.
EMI shielding (specialist applications)
For some federal, defence and high-security data centre rooms, HVAC duct is specified with EMI (electromagnetic interference) shielding to prevent emissions from the IT load propagating along the duct path. Typical solution: copper mesh or copper foil wrap on the duct exterior, bonded to the building EMI grounding system. SBKJ supplies the standard galvanised duct; the EMI shield is applied by a specialist contractor.
Equipment list for a data centre HVAC duct fabricator
A fabrication shop targeting the data centre construction market needs the following minimum equipment fleet to deliver hyperscale volumes:
- SBAL-V auto duct production line (rectangular supply and return) — running 1,500–2,500 m²/day single-shift, multi-shift capable
- SBTF-1602 spiral tubeformer (round duct for branches and economiser intakes) — Φ80–1,600 mm, flying shear
- SBTF-2020 spiral tubeformer (large-diameter risers) — Φ800–2,000 mm, for trunk and main risers
- TDF flange forming machine — connects rectangular sections, primary joint type
- SBLC lockformer — Pittsburgh seam forming for rectangular duct
- CNC plasma cutter (1500 × 6000 mm bed) — high-throughput blank cutting
- Hydraulic shear and folding — for fittings, transitions and reducers
- Welding station — for any continuous-weld sections (acoustic chambers, special fittings)
- Auxiliary — auto corner mounting, hoop machine, run-out tables
This fleet costs approximately USD 700,000–950,000 ex-works from SBKJ, plus freight, customs and rigging. With 2-shift operation it can sustain 6,000–10,000 m²/month of finished duct, sufficient for one mid-sized hyperscale project at any given time.
Throughput planning for hyperscale projects
A 50 MW hyperscale build typically demands HVAC duct delivery of 8,000–15,000 m² distributed over 12–18 months. The fabricator's planning challenge is matching site demand pull against fabrication production push. Common patterns:
- Front-loaded delivery for early-stage shell-and-core (large risers, main horizontals, plant room duct)
- Mid-cycle peak for fitout phase (branch ducts, terminal connections, fire-rated wraps)
- Back-loaded fittings for commissioning (custom adapters, terminal fittings, balancing dampers)
Multi-shift operation on the SBAL-V is the normal answer to peak-cycle demand. With 3-shift operation, an SBAL-V can sustain 7,500 m²/month — sufficient for a single hyperscale project on its own. Multi-line fabricators (2 SBAL-V cells) can serve multiple concurrent hyperscale projects.
Quality acceptance criteria
Hyperscale projects audit duct quality against very tight tolerances. Typical acceptance criteria:
- Length tolerance: ±2 mm on sections up to 2 m, ±5 mm above 2 m
- Squareness: corner-to-corner diagonal within ±3 mm
- Leak rate: SMACNA Class A (or EN Class C / AS-NZS Class C equivalent) at +2 in.wg test
- Reinforcement spacing: per SMACNA tables for the specified pressure class
- Surface finish: no visible scratches longer than 50 mm, no dents deeper than 0.5 mm
- Galvanising integrity: no zinc disturbance from forming or handling visible to the eye
SBKJ machines are configured by default to meet these tolerances; the limiting factor in field acceptance is usually handling damage between fabrication shop and installation, not the fabrication itself.
Why SBKJ for data centre HVAC duct fabricators
- Proven hyperscale references in Australia, Saudi Arabia, Singapore, Vietnam, Indonesia (NDA-protected list available)
- Multi-standard PLC recipes (SMACNA, EN 1505, AS/NZS 4254, DW/144) for fabricators bidding across regions
- Multi-shift capability with full hot-handover documentation between shifts
- FAT testing at SMACNA Class A at our partner production facility before shipment
- Strong parts continuity over 10+ years for fabricators committing to long data centre programmes
- Australia office for English-speaking after-sales coordination on Australian and SE Asian projects
Get a data-centre-ready SBKJ quotation →
FAQ
What duct standard applies to data centre HVAC?
SMACNA dominates in North America/ME/international, EN 1505 in Europe, AS/NZS 4254 in Australia/NZ. ASHRAE TC 9.9 governs cooling design; UL 1978 / EN 1366-1 / BS 476 govern fire-rated construction.
What gauge sheet metal is used?
Galvanised steel, gauge per SMACNA pressure class. 22-ga for ducts to 600 mm, 20-ga 600-1,200 mm, 18-ga to 1,500 mm, 16-ga above. Hot aisle return often one gauge heavier.
How is fire-rated duct different?
Standard galvanised duct wrapped with fire-rated insulation (Promat board, Cafco spray, 3M Interam wrap). The fab shop produces standard duct; fire wrap is applied on site.
Typical contract size?
50 MW hyperscale: AUD 8-15M HVAC duct supply. 5-15 MW colo: AUD 1.5-4M. Hyperscale demand is 8-15K m² over 12-18 months — needs at least one SBAL-V multi-shift.
Does SBKJ have data centre references?
Yes — Australia, Saudi Arabia, Singapore, Vietnam, Indonesia. Reference list available under NDA.
