PIR Pre-Insulated Duct vs Galvanized: A Cost and Installation Comparison

Every distributor and mechanical contractor eventually runs the same comparison: keep fabricating rectangular galvanized-iron duct on site, or move the air-distribution scope to a factory-made pre-insulated panel system. The answer is rarely universal. It depends on the building type, the duct routing, the labour rate you actually pay, the ceiling void you have, and — increasingly in Canada — on what the authority having jurisdiction will accept for a given occupancy.

This guide gives you the decision framework. It does not publish our prices, and deliberately does not quote savings percentages; the cost section below is a method — a list of line items you total in your own currency and labour rates. Any specification number in the tables comes from our published product data or from a document you must request from your supplier per project.

What the decision actually is

Strip away the material debate and there are only four decisions to make:

1. Scope boundary — who fabricates: your shop, a local sheet-metal subcontractor, or a panel supplier’s factory.
2. System type — galvanized-iron duct with field-applied external insulation, versus a composite panel that is structural and insulating in one product.
3. Installation method — cut-and-adhesive assembly in the ceiling void, versus traditional hanging, seaming, sealing and wrapping.
4. Evidence package — what you can put in the submittal so the engineer and the authority having jurisdiction accept the substitution.

If you cannot answer item 4, items 1–3 do not matter. Most failed substitutions in Canada fail on documentation, not on physics.

The two systems in plain terms

Galvanized-iron (GI) ducting is a metal air path. It is rigid, dimensionally stable, and universally understood by contractors, engineers and inspectors. It carries no thermal or acoustic value of its own, so an insulation layer is added — externally wrapped, or internally lined — and the assembly is finished on site. Its performance therefore depends on how well two separate trades executed two separate scopes.

PIR pre-insulated duct panel is a sandwich: aluminium foil facings bonded to a flame-resistant polyurethane core, produced under continuous pressure. The panel is the duct wall, the vapour barrier and the thermal insulation. Assembly is by cutting and adhesive connection rather than by metal fastening; accessories such as reamers, bending tools and rulers are part of the system.

Our Univer PIR pre-insulated duct panel is offered with the following published data:

Note the fire designation carefully. B1 is a material classification, not a duct assembly listing. In Canada the acceptance route for a duct system is normally a recognised duct standard and, where required, a certification mark carrying the Canadian “c” prefix. Those are separate questions from the panel’s own B1 rating, and they must be settled before you commit to a substitution. Ask your supplier which standard the assembly has been evaluated against, by which certification body, for which model range, and request the certificate — name, number, issuing body, validity and covered models. If that cannot be produced, treat the assembly as unverified for the project.

Specification comparison: what to tabulate

Do not compare “PIR versus GI” in the abstract. Compare the two assemblies against the same project schedule, column by column. A comparison table that survives an engineer’s review looks like this:

Two rows deserve emphasis because they are where submittals most often fall apart:

• Vapour control continuity. A foil-faced panel has an intrinsic vapour barrier only if every joint, penetration and field cut is effectively sealed. A GI system can have an excellent wrapped barrier defeated by one unsealed hanger penetration. Record who owns continuity and how it is inspected.
• Terminations. Panel duct does not accept a diffuser or a damper the way sheet metal does. Detail the transition at every diffuser and grille and every inline device before you price the job, not after.

The cost comparison as a method

Cost comparisons fail when they compare only the delivered material price per square metre. Totalled properly, a duct comparison has six buckets. Build your own sheet with these headers and your own numbers.

1. Material, delivered Panel or sheet metal, insulation, adhesives, sealants, foil tape, hangers, reinforcement, fasteners, dampers, grilles and any factory or site-applied coatings. Include freight, duties and the packaging/loading assumptions you were quoted — a per-square-metre price without an Incoterm is not a comparable number.

2. Fabrication labour GI: shop hours for cutting, notching, bending, seaming, reinforcing, plus liner or wrap labour. PIR: cutting, grooving, adhesive application, fitting assembly, plus the tool kit. Record hours per fitting type, not per project — fittings, not straights, decide the labour outcome.

3. Installation labour and access Hanging, joining, sealing, insulation finishing, and the man-hours lost to a congested ceiling void. This is where a lighter panel usually changes the arithmetic, and it is also where a contractor’s own historical data beats any supplier claim. Use your own crew’s productivity figures.

4. Ancillary trades and elapsed time Scaffolding or lifts, extended-hours premiums, drying or weather protection, cleaning after fabrication, and the schedule effect of a two-trade (metal then insulation) sequence versus a single-trade panel sequence. On occupied-building work, elapsed time is frequently the largest single term.

5. Verification and inspection Testing, documentation, rework from failed inspections, and the cost of any third-party review. If the assembly does not carry the documentation the specifier expects, this bucket can absorb the entire apparent material saving.

6. Lifecycle and service Cleaning regime, damage repair method, access panel provisions, and the cost of matching a discontinued panel thickness or fitting later in the building’s life. Ask how a damaged section is repaired in service — with a panel system, the answer should be a documented field repair, not a workaround.

Two rules keep this honest. First, present the comparison at the same scope: if the GI column includes the insulation trade, the PIR column must include sealing, terminations and hanger adaptation. Second, attach the productivity assumptions to named labour rates and date them; a comparison without dated assumptions is a marketing document.

Where each system tends to win

Treat the table as a starting hypothesis, not a conclusion. Every row still has to be checked against the project’s occupancy, the applicable code, and the certifications your supplier can actually produce.

What belongs in the submittal

For an engineer to accept a panel system, the submittal package should contain, at minimum:

• Manufacturer product data with thicknesses offered and the physical properties you are relying on.
• The fire classification of the core material and the duct assembly standard referenced, with the certification mark and its “c” prefix status stated explicitly where the project is in Canada.
• Fabrication drawings showing panel thickness by duct size, fitting details, reinforcement, hanger locations and maximum spacing.
• Joint and sealing detail: adhesive type, application method, cure requirements, and the inspection point before the void closes.
• Termination details at every air device, damper and equipment connection, cross-referenced to the diffusers and grilles schedule and to any EC inline duct fan or other inline device.
• Handling and storage requirements, including the temperature and humidity window for assembly.
• A repair procedure for in-service damage.
• Where the project is in Quebec, the bilingual documentation and marking obligations described below.

Keep the submittal to what you can evidence. A page of unverifiable comparative claims weakens an otherwise strong package.

Common failure modes

• Treating B1 as a duct listing. A material classification and an assembly listing are different things; conflating them is the fastest way to fail an inspection.
• Assuming North American certification. A certificate issued for another market is not automatically acceptable in Canada. Canadian marks carry a “c” prefix (for example cCSA, cETL, cUL); confirm the prefix, the issuing body and the covered models per project.
• Pricing material only. The delivered panel price is one of six buckets. Contractors who lose money on a switch usually lost it in terminations and inspection, not in the panel.
• Fabricating wet. Adhesive assembly in a damp, dusty or unconditioned void produces joints that look closed and are not. Confirm the storage, handling and assembly conditions the panel supplier requires, and sequence the work accordingly.
• Detailing terminations late. Dampers, diffusers and fan connections are the hardest part of a panel system. Detail them at tender stage.
• Ignoring acoustic intent. If the design relied on an internal liner for insertion loss, substituting a bare foil-faced panel changes the acoustic result. Ask for attenuation data for the specified thickness.
• Discovering the language obligation after printing. In Quebec, commercial publications, product markings and documents supplied with a product are subject to French-language requirements. Duct labels, installation instructions and warranty documents are in scope, and machine translation does not meet the quality standard the regulator expects. Plan bilingual documents and markings into the order, not into a reprint.

A worked sequence you can reuse

1. Take off the duct schedule by size band, separating straights, fittings and terminations.
2. Mark the routing by environment: conditioned indoor, unconditioned, exterior, high-temperature, wet or grease-laden.
3. Collect supplier data for the panel thickness you intend to use, and specifically the assembly standard and certification status.
4. Build the six-bucket cost sheet with your own labour rates and your own productivity history.
5. Run a sensitivity check: if installation labour moves by a realistic margin, does the choice change? If the answer flips easily, the decision is labour-driven and should be made by the installing contractor, not by the buyer.
6. Issue the submittal package and get written acceptance of the substitution before the order is placed.
7. Hold a pre-installation meeting covering storage conditions, adhesive method, joint inspection and termination details.

What to confirm with your supplier

• The exact standard the duct assembly has been evaluated against, by which certification body, and whether the mark carries the Canadian “c” prefix for the models you are buying.
• Certificate number, issuing body, validity period and the covered model range — in writing, before the order.
• Panel thickness recommendation by duct size and static pressure, and the reinforcement and hanger schedule that goes with it.
• Storage, handling and assembly conditions (temperature, humidity, cleanliness) and the adhesive system’s cure requirements.
• Attenuation, weight per m² and vapour-barrier continuity details for the specified thickness.
• Termination details for dampers, diffusers, grilles and inline fans, and any limits on fitting geometry.
• French-language marking and documentation availability for Quebec-bound shipments, and the labels that will physically appear on the product and its packaging.
• Whether the shipment carries the NRCan energy-efficiency reporting information your customs broker will need, since regulated energy-using products require reporting at import.

When you are ready to compare a panel system against your current duct scope, send the duct schedule and the project conditions through our RFQ channel, or review the ventilation and IAQ solutions range and the resources library for the matching guides and checklists.