How to estimate ACM (aluminium composite panel) cladding
Reza7 min read
To estimate ACM cladding, find your finish codes on the elevations, read each one in the finish schedule, check the wall types, then find those walls on the setout plans. Take lengths from the floor plans and heights from the sections. List every scope item, price each on your own rates, and apply waste and margin once.
Draft.This article hasn’t had its final edit yet, so treat anything specific in it as provisional.
ACM looks simple on the elevations: a grid of flat panels in one or two colours. The price is anything but. On a tray system each panel is cut from flat sheet and folded into a tray, with returns at the edges, fixed to a subframe that may not appear on any elevation. Miss a wall, a return or a flashing and the job loses money before anyone picks up a drill.
This is the method I use as a facade estimator. It has no figures in it on purpose: waste, rates and prices belong to your business, and the right ones come from your own finished jobs. Where a figure goes, I'll show you where.
What makes ACM cladding different to estimate?
Three things set it apart from sheet or board cladding.
- Each panel is a fabricated item. On a tray system the panel is cut and folded from flat sheet, so its size, its returns and its layout drive the material and the fabrication cost, not just the wall area.
- The joints are part of the design. Joint and reveal widths are usually set by the architect, and they decide the panel layout, the subframe positions and how many panels are unique.
- The cost hides behind the face. The subframe, top hats, brackets, flashings and fixings need as much attention as the panels, and they come from the wall types and details, not the elevations.
Which drawings do you need to estimate ACM cladding?
The same set as any cladding job, plus the facade details. No single sheet gives you an accurate quantity.
| Drawing | What you take from it for ACM |
|---|---|
| Elevations | Where each ACM finish code is, and the panel layout if the architect drew one |
| Finish schedule | What each code is: product, colour, finish, thickness |
| Wall types | The build-up behind the panel: substrate, subframe, insulation, cavity |
| Wall setout plans | Which walls carry each wall type, including ones hidden on the elevations |
| Floor plans | True lengths, including returns, setbacks and angled walls |
| Sections | True heights: floor to floor, parapets, soffits and slab edges |
| Facade details and specification | Joints, reveals, corners, flashings, fixings and the performance requirements |
How do you measure ACM cladding from the drawings?
Work in this order. Each step answers a question the one before it can't.
- Find your codes on the elevations. Mark every ACM finish code in your scope and note which faces of the building it appears on.
- Read each code in the finish schedule. Two codes that look the same on the elevation can be two colours, two finishes or two thicknesses, with two different rates.
- Check the wall types. Find every wall type that includes ACM, and note the subframe, insulation and substrate behind it.
- Find those walls on the setout plans. Courtyards, recesses, returns and walls behind balconies often carry ACM that no elevation shows clearly.
- Take the lengths from the floor plans. Every wall at its true length, following returns, setbacks and angled walls.
- Take the heights from the sections. Where the height changes along a wall, the section shows you where.
- Combine them wall by wall. Length from the plan times height from the section, less the openings. Keep each wall as its own measurement so you can find it again.
- Measure the linear items separately. Corners, joints, flashings and the edges around openings are lengths, not areas, and they are priced differently.
Then go back to the elevations as a check. If you can see a panel you haven't measured, you've missed a wall. The full method, with why the elevations alone mislead you, is in how to price a cladding job from the drawings.
What scope items belong in an ACM estimate?
Use this as a checklist. Each item should be its own line, so the price shows what you allowed for.
| Scope item | Where to find it | What to check |
|---|---|---|
| Subframe and top hats | Wall types, facade details | The system, spacing and brackets the details call for, and what they fix back to |
| Panel fabrication | Elevations, details, specification | The tray shape, folded returns, notched corners and how many panels are one-offs |
| Joints and reveals | Elevations, details | The joint and reveal widths the architect set, and whether they are open or sealed |
| Flashings | Details, sections | Head, sill, jamb, base and parapet flashings, measured as lengths |
| Corners | Plans, details | External and internal corners, folded or formed, measured as lengths or counts |
| Penetrations | Elevations, services drawings | Vents, pipes and fixtures through the face, counted and detailed |
| Fixings | Details, specification | The fixing type and method the specification names, for panels and subframe |
| Access and hire | Sections, site plan | Scaffold, elevated work platforms or swing stages, and how long you'll need them |
| Fire performance evidence | Specification | Check the specification and NCC requirements for the project, and price the evidence the specification asks for |
Anything the drawings don't settle goes in your inclusions and exclusions, or becomes a question to the builder. That is where variations are won or lost later.
How do you build up the price on your own rates?
Price each scope item as labour, material, subbie and hire, plus fabrication as its own cost code if you make or buy the panel trays separately, all under your own cost codes. Every rate comes from your business, not from an article.
| Cost type | Typical lines on an ACM job | Where the figure comes from |
|---|---|---|
| Material | ACM sheet, subframe, top hats, flashings, fixings, sealants | Your supplier's current quote, priced against your measurements |
| Fabrication | Cutting, routing and folding the panel trays | Your own figure from past jobs, or your fabricator's quote |
| Labour | Subframe, panel installation, flashings, sealing | Your own figure from past jobs, against each measurement |
| Subbie | Any part you let to another trade | Their quote, compared with your own allowance |
| Hire | Scaffold, platforms, swing stages | Your hire supplier's rate for the time the programme needs |
Each line is the same shape: a quantity from your takeoff, times your rate, under a cost code. When you're unsure of a rate, look at what you charged on the last job that carried it. Subino's rate finder searches every line you've priced and shows the rate on each job, with the material rate separate from the installed rate.
Where should waste and margin be applied?
Once each, across the whole estimate, at the end.
- Waste: put your own waste figure from past jobs in one place, applied across the material lines, not inside each wall's measurement. Hide it in the quantities and it gets added twice, or forgotten on half the job.
- Preliminaries and margin: apply them once across the lot, after the lines are priced. Adding margin by hand to some lines and not others is one of the easiest ways to lose money on a tender.
In Subino's cost sheet, waste, preliminaries and markup are applied across every line for you (set the job's margin and preliminaries), so you set each figure once.
Where do ACM estimates usually go wrong?
| Where it slips | What it looks like | What stops it |
|---|---|---|
| Measured off the elevations only | Returns, setbacks and angled walls short | Lengths from the plans, heights from the sections |
| Area priced, panels ignored | Folded returns and one-off panels missing from the fabrication cost | Fabrication priced as its own line from the panel layout |
| Subframe left to the end | Top hats and brackets under-allowed or missed | Subframe measured from the wall types and details |
| Linear items forgotten | Flashings and corners priced as an afterthought | Every linear item measured as its own length |
| Waste and margin applied twice | A price that looks high on some lines and thin on others | Waste, preliminaries and margin applied once across the lot |
How do you keep the estimate right through revisions and replacement panels?
Keep the quantities with the price. In Subino the measurements are held against the scope they belong to, inside the revision you priced (measurements that stay with the price). Name a measurement once and every line built on it follows, and last year's revision keeps the quantities it was priced against. Start your next ACM job from a scope template of this one.
Once the job is running, damaged or changed panels come back from site as hand sketches. Subino's panel drawings turn a photographed sketch into a checked drawing and a CNC-ready DXF. I've written that up in cladding panel drawings to a CNC-ready DXF.
When you win, the estimate becomes the budget without retyping (win it, and the estimate is the budget). Pricing shows what each plan includes. If you'd like to see it on an ACM job you've already priced, book a 15-minute demo and bring the drawings.
Frequently asked questions
What waste allowance should I use for ACM panels?
Use your own figure from past jobs. Waste on ACM depends on the panel layout, the sheet sizes your supplier offers, the folded returns and how many panels are one-offs, so a number from someone else's job tells you little. Record what you actually used on each job, and apply waste once across the lot, not inside every measurement.
Can I measure ACM cladding from the elevations?
Not on their own. The elevations tell you where each finish code is, but they hide setbacks, leave out walls behind other parts of the building and show angled walls shorter than they are. Take the lengths from the floor plans or wall setouts and the heights from the sections, and use the elevations as a final check.
What should an ACM cladding estimate include?
At least the subframe and top hats, panel fabrication including folded returns, the joints and reveals, flashings, corners, penetrations, fixings, access and hire, and whatever fire performance evidence the specification asks for. Each one should be its own line, priced on your own rates, so you can show what you allowed for.
Do I need to check fire requirements for ACM cladding?
Yes. Check the specification and NCC requirements for the project, and price whatever evidence and documentation the specification asks you to provide for the panel. This article doesn't give compliance advice. If the documents are unclear or disagree, raise it as an RFI to the builder before the tender closes.
How do I price labour for ACM cladding?
On your own rates and your own figures from past jobs. Break the labour into the work it covers, such as subframe, panel installation, flashings and sealing, and price each against its own measurement. A figure you can trace back to a finished job is worth more than any rule of thumb.