How to Compare PIR and PUR Sandwich Panel Suppliers

When comparing PIR and PUR sandwich panel suppliers, make sure everyone is quoting the same thing first. Core type, thickness, steel facings, coating, thermal data, fire reports, joints, structural data, factory QC, delivery, packing, and warranty all need to line up. If a supplier cannot meet a required fire, thermal, structural, or compliance condition, there is no point comparing its price with the others.

RFQ Data to Send

You may see common options such as 50, 75–80, 100, 120–125, 150, or 200 mm cores, effective widths around 1,000–1,200 mm, and steel facings such as 0.40, 0.50, or 0.60 mm. These are only common product examples. They are not fixed industry requirements.

A proper RFQ could look like this:

100 mm PIR wall panel, 0.50 mm outer steel, 0.40 mm inner steel, specified pre-painted metallic-coated steel, 1,000 mm effective width, concealed joint, project-required thermal and fire documentation, FOB quotation.

Ask every supplier to write down any change from your RFQ. If you ask for 0.50 mm steel and the factory wants to quote 0.45 mm, that needs to be shown clearly instead of being buried in a technical sheet.

The same rule applies when comparing Chinese suppliers for other manufactured products: send the same requirement to everyone before you compare price.

Mandatory Pass/Fail Check

Price comes later. If the project requires a certain fire result and the supplier cannot meet it, a lower price does not fix that problem.

Only compare commercial terms after the basic technical requirements have passed.

PIR or PUR Decision

If the project already specifies PIR, compare PIR suppliers. If it specifies PUR, compare PUR suppliers. Do not switch from one to the other just because one quotation is cheaper.

If the core has not been decided yet, look at what the project actually needs:

• Fire performance
• Thermal performance
• Service temperature
• Project approval requirements
• Insurance requirements
• Total installed cost

PIR is often used where better fire behavior is needed, but “PIR” by itself is not a fire rating. Both PUR and PIR are combustible insulation materials. What matters is how the complete panel system has been tested and approved.^[1]

Market Compliance Documents

The documents you need depend on where the panels will be used.

For EU projects, check:

• Applicable harmonised technical specification
• Required declared characteristics
• Applicable declaration documents
• CE marking requirements
• Project-specific fire and structural requirements
• National building rules

Harmonised European standards provide the common technical basis used to assess and declare construction-product performance.^[2]

The EU Construction Products Regulation is now in a transition period under Regulation (EU) 2024/3110. Most provisions started applying from 8 January 2026, while parts of the earlier CPR framework still apply during the transition.^[3]

So “CE available” is not enough. Ask which technical specification applies, which declaration is being supplied, and whether those documents cover the exact panel in your order.

Fire Report Match Check

Here is a simple example:

The report may be genuine, but it may not cover what you are buying.

Reaction-to-fire results can depend on the panel form, fixing, joints, mounting method, and orientation. UK government guidance warns against using one classification for different product configurations without checking the permitted field of application.^[4]

For the buyer, the question is simple: does this report actually cover my panel?

Fire Label Check

The European reaction-to-fire system includes classes A1, A2, B, C, D, E, and F, with extra smoke and flaming-droplet classes where they apply.^[5]

A result such as B-s1,d0 is a reaction-to-fire classification. It is not the same as saying a wall has a certain fire-resistance time.

ASTM E84 is another test buyers often misunderstand. It reports flame-spread and smoke-developed indices under the test conditions. ASTM also states that the flame-spread index alone cannot be used to call a material noncombustible.^[6]

When two suppliers show different fire labels, compare them in this order:

standard → result → tested panel → permitted application

Thermal Data Check

For example:

This comparison only works if both suppliers use the same agreed calculation basis.

Do not put one supplier’s fresh foam test value next to another supplier’s declared finished-panel value and treat them as equal data.

Steel Facing Check

Both suppliers can call this a “100 mm PIR panel,” but the products are not the same.

For the steel facings, check:

• Outer base metal thickness
• Inner base metal thickness
• Thickness tolerance
• Steel grade or strength where required
• Metallic coating
• Paint system
• Paint thickness where specified

Also ask whether “0.50 mm” means the base metal thickness or the total thickness after coating.

On a 10,000 m² order, changing both facings from 0.50 mm to 0.40 mm can lower the quotation because less steel is being supplied. That is a different specification, not simply a cheaper price for the same panel.

Coating Check

Ask the supplier to state the metallic coating, paint system, coating thickness where relevant, and the environments it is meant for.

Then read the warranty exclusions. Coastal exposure, chemicals, cleaning methods, and maintenance can all affect what the coating warranty actually covers.

Core QC Check

If density is part of the PO, write both the nominal value and the tolerance into the specification.

Example:

The ±2 kg/m³ tolerance here is only an example of an agreed purchase requirement. It is not a universal PIR or PUR tolerance.

Depending on the product and project, core data may also include:

• Thermal conductivity
• Compressive strength
• Shear strength
• Tensile properties
• Dimensional stability
• Closed-cell content

ASTM E1730 is a useful example. Within its specific scope for PUR/PIR structural sandwich-panel cores used in shelter construction, it covers more than density, including thermal conductivity, compressive strength, shear strength, closed-cell content, and dimensional stability.^[7]

Joint and Bonding Check

Ask for a panel cross-section before ordering. It should show:

• Tongue and groove
• Main seal
• Fastener position
• Roof overlap where used
• Water path
• Thermal bridge
• Allowed installation gap

On finished panels, look for:

• Loose steel skins
• Delamination
• Blistering
• Foam voids
• Damaged tongues
• Uneven grooves
• Open edge bonding

For cold rooms, the seals around corners, floors, ceilings, doors, pipes, and cable openings matter just as much as the main panel joint.

For roofs, also check side laps, end laps where used, ridge details, eaves, and roof penetrations.

Dimensional Check

Do not wait until inspection day to argue about tolerances. Put them in the PO first.

Example:

The ±2 mm panel tolerance shown here is only an example. Use the applicable standard or the tolerance agreed in the purchase specification.

Cold-Room Check

• Air seal around every joint
• Vapor seal continuity
• Wall-to-floor connection
• Wall-to-ceiling connection
• Door frame detail
• Pipe and cable penetrations
• Internal surface coating
• Condensation risk
• Ceiling support design

Do not assume a cold-room ceiling can carry workers, pipes, cables, or other loads unless the design says it can.

The UK Health and Safety Executive reported a fatal cold-store ceiling failure involving insulated polyurethane sandwich panels and their supports. The alert points to support failure, corrosion, fatigue, and maintenance as issues that need proper engineering checks.^[8]

Structural Data Check

Ask for the load-span table for the exact panel you are buying.

A brochure saying “maximum span 6 m” tells you very little on its own. That 6 m figure only makes sense together with the load, fixing, support, steel, and panel conditions used to produce it.

Final structural selection should be checked by the project engineer.

Factory QC Check

During a supplier audit, check whether the factory actually records and controls:

• Incoming steel
• Foam chemical batches
• Panel dimensions
• Density where specified
• Joint dimensions
• Bonding
• Surface defects
• Production settings

For each item, ask:

• How often is it checked?
• Who signs the record?
• What measuring tool is used?
• When was it last calibrated where calibration is required?
• What happens if the result is outside the limit?

For example, if five thickness checks in a row are outside tolerance, the factory should be able to show which panels were affected, what was adjusted, what was rechecked, and what happened to the suspect panels.

ISO 9001 can show that a company has a documented quality-management system. It does not prove that one particular panel has a certain fire rating, U-value, or load capacity.^[9]

Traceability Check

The factory should be able to link the finished goods back to the production records.

That can include:

• PO number
• Production date
• Steel coil batch
• Polyol batch
• Isocyanate batch
• Inspection record
• Production batch

Bundle labels can show:

• Panel type
• Thickness
• Length
• Quantity
• Bundle number
• Order number

If 40 panels out of a 500-panel shipment show the same problem, good traceability should help the supplier work out whether those panels came from the same steel coil, chemical batch, shift, or production period.

Supplier Identity Check

Different company names are not always a problem, but the relationship needs to make sense.

If Factory A is on the test report, Company B signs the contract, and Company C receives payment, find out who is responsible for manufacturing, quality, export, warranty, and claims before you pay.

This is part of normal supplier due diligence.

Quote Normalization

Do not rank these quotations by price until the steel, coating, fire documents, accessories, packing, effective width, and Incoterm have been put on the same basis.

For building-material sourcing, also check whether flashings, profiles, fasteners, sealants, and other installation items are included or quoted separately.

Total Cost Check

Example:

This is only an example, not an industry cost benchmark.

When comparing total cost, include:

• Panel price
• Accessories
• Domestic transport
• Export charges
• International freight
• Import costs
• Unloading
• Damage
• Replacements
• Installation labor
• Rework
• Delay cost

Capacity and Lead-Time Check

Example order:

• Quantity: 30,000 m²
• Available production: 3,000 m²/day

30,000 ÷ 3,000 = 10 production days.

That is only the production time.

If the order also needs:

• 5 working days for raw materials
• 10 production days
• 2 working days for inspection and packing

the factory schedule is already 17 working days before allowing for rework, holidays, or shipping space.

Ask the supplier to confirm:

• Raw-material lead time
• Production start date
• Available daily output
• Expected completion date
• Inspection date
• Packing date
• Loading date

The same issue comes up in other manufacturing projects in China: the factory’s maximum capacity is less useful than the capacity actually available for your order.

Packing and Unloading Check

For each bundle, record:

• Bundle number
• Panel quantity
• Panel lengths
• Bundle dimensions
• Bundle weight
• Order number

Example:

Check edge protection, bottom supports, top protection, strapping, and water protection before loading.

Also confirm:

• Whether a forklift can be used
• Required fork spacing
• Whether a crane is needed
• Whether soft straps are needed
• Whether a spreader beam is needed
• Maximum bundle weight
• Required support points

Inspection Plan

Before production:

• Approved specification
• Approved drawings
• Approved sample where required
• Approved materials
• Inspection criteria

During production:

• Steel specification
• Panel dimensions
• Core checks
• Joint shape
• Bonding
• Production records

Before shipment:

• Quantity
• Dimensions
• Surface quality
• Joint condition
• Labels
• Accessories
• Packing

If the shipment has 20 bundles, do not take every sample from Bundle 1.

If 10 panels are measured, spreading those checks across several bundles and production batches gives a better picture of consistency than measuring 10 panels from the same stack.

The actual sample size and acceptance rule should follow the inspection plan agreed for the order.

A multi-stage inspection can catch problems earlier, before all panels are finished and packed.

A final pre-shipment inspection can then check selected dimensions, quantity, workmanship, accessories, labels, and packing before loading.

Contract Acceptance Rules

Put the important product details into the PO or contract:

• Core type
• Panel thickness
• Core specification
• Steel thickness
• Steel grade where required
• Metallic coating
• Paint system
• Effective width
• Panel lengths
• Joint
• Thermal requirement
• Fire-report reference
• Structural requirement
• Accessories
• Packing
• Inspection method
• Delivery date

Also agree what happens when something fails:

• Production hold
• Rework
• Replacement
• Reinspection
• Approved price adjustment
• Rejection

A small surface scratch and a failure to meet a required fire classification are not the same type of defect and should not be handled the same way.

Warranty and Claim Check

Replacing 20 defective panels may involve much more than supplying 20 new panels. Flashings may need to come off, lifting equipment may be needed, installed panels may need to be removed, and nearby work may need repair.

That is why a material-only warranty can still leave the buyer with a large bill.

Final Supplier Comparison

Red Flags

• Fire report cannot be verified
• Report covers a clearly different product
• Factory identity is unclear
• Payment company cannot be explained
• Steel thickness basis is unclear
• Technical values change during negotiation
• No written tolerances
• No joint drawing
• No batch traceability
• Production capacity does not match promised delivery
• Supplier refuses reasonable inspection
• Important raw materials can change without control

Documents to Collect

Before order:

• Final quotation
• Technical data sheet
• Panel drawing
• Joint drawing
• Steel and coating specification
• Thermal data
• Fire documents
• Structural data where required
• Installation instructions
• Warranty

Before shipment:

• Inspection report
• Packing list
• Bundle list
• Batch identification
• Required production records
• Accessory list
• Shipping documents

Before shipment, make sure the quotation, drawings, fire report, thermal data, PO, inspection report, and bundle labels are all describing the same panel.

Finally

Start by removing suppliers that cannot meet the required fire, thermal, structural, or market rules. Then compare the details that change the real cost: core thickness, effective width, steel thickness, coating, accessories, packing, and Incoterm. A 100 mm PIR panel with 0.50/0.50 mm steel is not the same as one with 0.40/0.40 mm steel. A 30,000 m² order at 3,000 m² per day also needs time for raw materials, inspection, packing, and loading. Before shipment, check that the PO, test reports, QC records, bundle labels, and inspected goods all match.