Guides / Facade Systems
A per-square-metre aluminium cladding price is a composite number, not a material price. It can mean the sheet alone, the fabricated panel, or the finished wall including sub-frame and labour. Knowing which one you have been quoted is what makes two prices comparable, and it is usually the reason two quotes for the same elevation land far apart.
This page breaks the number into its parts, using our own aluminium composite sheet specification as the reference, then sets out how to line two quotes up side by side. It does not publish a unit rate, because a rate without the build-up attached is the thing that causes the argument later.
Divide the quote by the right area before you compare it. Ask whether the rate is on sheet area, on fabricated panel area, or on wall area. A 1220 × 2440 mm sheet is 2.98 m² of material; the wall it eventually covers is less than that once cutting loss, joints and openings are taken out. A rate on wall area already carries the wastage, so it is normally the higher number for the same sheet.
Then check the build-up, not just the rate. On a composite panel the aluminium skin runs from 0.21 mm to 0.50 mm per side and is the largest single cost inside the sheet; coating, core and quantity follow. Two quotes that look far apart are usually two different products, and the cheaper one is thinner somewhere the drawing did not name.
Both suppliers say they priced what you sent, and the numbers are nothing like each other. Almost always one of four things has happened.
None of that is dishonesty. A rate sent without a build-up behind it cannot be compared with anything, and the fix sits on the buyer's side: send an RFQ specific enough that the reply has to name each part.
Eight lines. A quote that shows them can be checked; a quote that shows one cannot.
| Line | What it contains | Where it hides |
|---|---|---|
| Sheet | Composite panel at the specified total and skin thickness, 1220 × 2440 mm or cut to order | Usually the only visible line in a cheap quote |
| Fabrication | Cutting to the panel schedule, routing, folded returns, corner joints, stiffeners where the panel spans | Absent when the quote says sheets |
| Sub-frame | Vertical and horizontal members, brackets, shims, anchors to the structural substrate | Often a separate trade, sometimes simply missing |
| Fixings and sealant | Rivets or cleats, gaskets, backer rod, weather sealant, fastener corrosion class | Priced later as extras |
| Flashing and trims | Head, sill, jamb and corner pieces, parapet capping, movement joints | Discovered at installation |
| Wastage | Cutting loss on a 1220 × 2440 sheet, offcuts that cannot be reused, damaged sheets | Rolled into the rate, or billed as overage |
| Packing and freight | Protective film, timber crate or pallet, sea freight to the nominated port | Quoted ex works and left for the buyer |
| Labour | Installation, access equipment, supervision, making good | Rarely in a supplier's rate at all |
Method statement and inspection points for our own facade packages are on how we inspect; the material and fire documentation a project normally asks for is on certifications.
Everything else is arithmetic. These five are worth negotiating, because they change the product rather than the margin.
Two smaller ones are worth naming anyway: the destination port, because freight is quoted per shipment rather than per square metre, and the packing method, because a crate that survives a sea leg costs more than a pallet that does not.
Three different areas get called the area, and the difference is not academic.
A rate on wall area can be compared with another rate on wall area. A rate on sheet area set against a rate on wall area will always look like a bargain, and the difference lands on the buyer at the first delivery.
Put both on one sheet, in this order. The row that cannot be filled is the row to question.
| Check | What to write down |
|---|---|
| Area basis | Sheet, fabricated panel or wall area, and the measured quantity behind it |
| Total thickness | 3, 4, 5 or 6 mm, stated as total |
| Skin thickness | mm per side, stated separately from the total |
| Coating | PE, PVDF, nano or specialty, with the colour reference |
| Core and fire class | Polyethylene or mineral, and the class the project requires |
| Fabrication in scope | Cutting list, folding, returns, stiffeners, corner details |
| Framing in scope | Sub-frame, brackets and anchors, or explicitly excluded |
| Fixings, sealant, trims | Included, or listed as excluded with a price against each |
| Wastage | Percentage allowed, and who carries what is left over |
| Delivery basis | Ex works, FOB or delivered, named port, packing method |
| Validity | How long the rate holds, and what happens if the alloy price moves |
Colour has to be confirmed against a physical chart rather than a screen image, on both quotes, or the two panels will not match on site even when every number does.
Eight items. A supplier who receives all eight can price once; a supplier who receives three will price, be asked to revise, and price again.
Send the drawings rather than a description of them. A facade question answered from a paragraph is a guess with a price attached; answered from the elevation, it is a quote. There is a drawing upload on send drawings for exactly that.
It depends on what the supplier is quoting, and that is the first thing to establish. A sheet-only figure covers the panel cut from a 1220 × 2440 mm sheet. A fabricated-panel figure adds folding, routing, returns and stiffeners. A wall-area figure, which is what an installer quotes, adds the sub-frame, brackets, fixings, sealant, flashing, wastage on cuts and labour. The three can be compared only after you know which one you are looking at.
Usually because they are not the same build-up. The aluminium skin on a composite sheet runs from 0.21 mm to 0.50 mm per side, and the skin is the largest single cost driver in the sheet. Add the coating (polyester for interior work, PVDF for exterior, or a nano or specialty finish), the core (standard polyethylene or a fire-rated mineral core graded B1 or A2), whether sheets are supplied full size or cut to order, and the freight lane. A wide spread between quotes is normal rather than suspicious.
Ask, because the two differ by the amount of cutting loss. A 1220 × 2440 mm sheet is 2.98 m² of material. Once panels are cut, folded and laid out with joints, the wall area covered is smaller than the sheet area consumed, and offcuts that cannot be reused are charged to the project. A quote on wall area already carries that loss, which is why it is normally the higher number for the same sheet.
Not necessarily, because sheet thickness and skin thickness are different numbers. A 4 mm panel can be built with a thin skin and a thick core, and a 3 mm panel with a heavier skin; the skin is what carries the cost. Specify skin thickness in millimetres per side and total panel thickness separately, or two suppliers will quote two different products under the same 4 mm description.
Panel thickness and skin thickness separately, alloy and temper, coating system and colour reference, core type and the fire classification required, sheet size or cut sizes with a cutting list, edge and joint detail, whether framing and fixings are in scope, packing method, destination port, and the date the quote is needed by. A quote that answers all of those can be compared. One that answers three of them cannot.
Where a figure depends on the project — area, wastage, freight, installation — it comes from the drawings and the shipping lane, not from this page.