Reading an ACP specification
| Parameter | Options in the market | What to specify | Consequence of the cheap option |
|---|---|---|---|
| Total thickness | 2 / 3 / 4 mm | 4 mm for facades, 3 mm internal | 3 mm oil-cans visibly on a large panel |
| Skin thickness | 0.21 / 0.25 / 0.30 / 0.50 mm | 0.50 mm external, 0.25 mm internal | Thin skin dents and shows every fixing |
| Core | PE / FR mineral filled / A2 | FR minimum for commercial | PE core is combustible and spreads flame |
| Coating | Polyester / PVDF | PVDF external, polyester internal | Polyester chalks and fades in 3–4 Mumbai summers |
| Fixing system | Adhesive / tray and cassette | Cassette on aluminium sub-frame | Direct-glued panels debond in heat |
| Sub-frame | MS / aluminium | Aluminium, or galvanised and painted MS | Untreated MS rusts through in coastal air |
2026 Indian rates
| Grade | Rate (₹/sq ft, material) | Installed rate | Typical use |
|---|---|---|---|
| 3 mm, 0.21 mm skin, PE core, polyester | ₹85 – 120 | ₹160 – 240 | Internal signage, shop boards |
| 3 mm, 0.25 mm skin, PE core, PVDF | ₹120 – 170 | ₹210 – 300 | Internal column cladding, counters |
| 4 mm, 0.30 mm skin, FR core, PVDF | ₹180 – 260 | ₹290 – 420 | Commercial internal cladding |
| 4 mm, 0.50 mm skin, FR core, PVDF | ₹240 – 350 | ₹380 – 550 | External facade, canopy soffits |
| Aluminium sub-frame and fixings | — | ₹90 – 180 | Included in the installed rates above |
Installed rates include the sub-frame, fabrication of trays, silicone jointing and fixing. Curved and folded work adds 20–40%.
Fire: the part that is not negotiable
Polyethylene-cored ACP burns, and it burns with the aluminium skins channelling flame up a facade. Indian commercial landlords and fire consultants increasingly prohibit it, and any competent fit-out specification will call for a fire-retardant mineral-filled core.
- For internal commercial cladding in a Mumbai office building, expect the landlord’s fit-out manual to require FR core with a test certificate. Submit it before ordering.
- Never clad a fire escape stair, a lift lobby or a corridor with PE-core ACP.
- A2 grade, with a predominantly mineral core, is the highest commonly available class and is specified on tall facades.
- Get the certificate for the actual batch, not a generic brochure page. Core substitution between quotation and delivery is a known problem in this market.
- Residential internal use — a feature wall, a counter front — carries much lower risk, but there is rarely a good reason not to use FR core anyway.
Mumbai coast, sun and the fixing detail
- Coating. PVDF is a fluoropolymer coating that holds colour and gloss for well over a decade. Polyester is a paint and in Mumbai’s UV it chalks within three to four summers, leaving a dusty, faded panel. For anything external, PVDF is the only sensible specification.
- Sub-frame. Salt air destroys untreated mild steel. Use aluminium sub-framing on any external or semi-external application, and hot-dip galvanised and painted MS at minimum elsewhere.
- Thermal movement. A 4 m aluminium panel in Mumbai sun moves several millimetres. Joints of 10–15 mm with backer rod and neutral-cure silicone, and slotted fixing holes, are how that movement is absorbed. Rigid fixing produces oil-canning and eventually cracked joints.
- Water. ACP cladding is not a waterproof layer. The wall behind it must be waterproofed and the cavity drained; a facade that relies on the silicone joints to keep water out will leak.
- Cleaning access. Specify how the facade will be cleaned before it is built. In a Mumbai building with no gondola, an external ACP facade may never be cleaned again.
Care, life and BOQ wording
- Wash externally once or twice a year with plain water and a soft brush. Do not use solvent or abrasive cleaners on PVDF.
- Expected life: 15–20 years for 4 mm PVDF externally; 5–8 years for polyester before visible fading.
- BOQ: “Cladding in 4 mm aluminium composite panel, 0.50 mm skins, fire-retardant mineral-filled core, PVDF coated; manufacturer’s batch test certificate for core classification to be submitted before delivery.”
- BOQ: “Fixed as cassette trays on an aluminium sub-frame with slotted fixings; 12 mm joints with backer rod and neutral-cure structural silicone.”
- BOQ: “Substrate to be waterproofed and cavity drained. ACP is not to be relied upon as the weatherproofing layer.”
Specification summary
| Property | Specification |
|---|---|
| Thickness | 4 mm external, 3 mm internal |
| Skin | 0.50 mm external, 0.25 mm internal minimum |
| Core | Fire-retardant mineral filled; A2 on tall facades |
| Coating | PVDF external, polyester acceptable internally |
| Sub-frame | Aluminium, or galvanised and painted MS |
| Joints | 10 – 15 mm with backer rod and neutral-cure silicone |
| Rate | ₹85 – 350 material; ₹160 – 550 installed, per sq ft |
| Life | 15 – 20 years with PVDF |
Frequently asked questions
What is the difference between PE and FR core ACP?+
PE core is solid polyethylene, which is combustible. FR core is polyethylene heavily filled with mineral, which resists ignition and does not propagate flame the same way. The price difference is roughly 40–70%, and for any commercial application the FR core is what should be specified.
How long does ACP last outdoors in Mumbai?+
Fifteen to twenty years with a PVDF coating and a 0.50 mm skin. With a polyester coating, visible chalking and colour loss start in three to four years. The coating, not the core, determines how it looks; the core determines how safe it is.
Can ACP be used as a waterproof facade?+
No. It is a rainscreen, not a waterproof layer. The wall behind it must be properly waterproofed and the cavity drained and vented. Facades that depend on silicone joints for weatherproofing leak within a few monsoons, usually at a corner.
Is ACP suitable for interior walls at home?+
It is used for feature walls and counter fronts and it performs well, but it reads as a commercial material in a domestic room. For the same money a veneered or fluted panel usually looks better. Where it does make sense at home is a balcony wall or an exposed external parapet.
How do I verify the grade I was quoted?+
Ask for the batch test certificate for core classification and a cut sample from the actual delivery. Cut a corner and look at the core: an FR core is visibly grey and mineral-loaded, a PE core is uniformly black or white plastic. Core substitution after quotation is a known problem.