Quick answer: Clean ACP cladding with plain water and a mild, neutral detergent using a soft sponge, rinse from top to bottom, and never use solvents, abrasives or high-pressure jets on joints. Just as important as cleaning: inspect the silicone joints, panel edges, fixings and sub-frame at least once a year, ideally before the monsoon. Most ACP problems start behind the panel, not on its face.
Why ACP needs maintenance at all
ACP is low-maintenance, not no-maintenance. In our region it faces:
- Strong UV that ages coatings and sealants.
- Dust and vehicle grime on busy roads.
- Monsoon rain that tests every joint.
- Salt air along the Kerala and Tamil Nadu coasts that corrodes untreated steel and fixings.
- Bird droppings, which are acidic and can mark the coating if left for long.
A simple routine keeps the facade looking good and catches small problems before they become leaks or loose panels.
How to clean ACP sheets safely
What you need
- Clean water (soft water if possible, to avoid spots)
- A mild, neutral (pH-neutral) liquid detergent
- Soft sponge, microfibre cloth or soft brush
- A low-pressure hose
- Safe access: ladder for ground floor; scaffolding or rope access by trained people for height
Step by step
- Rinse first with clean water to remove loose dust and grit, so you do not scratch the surface while washing.
- Wash gently with the detergent solution, working in small areas.
- Work top to bottom, so dirty water does not run over cleaned panels.
- Rinse thoroughly with clean water before the solution dries.
- Dry or let air-dry; wipe any water spots on dark colours.
- Avoid cleaning in strong midday sun; the solution dries too fast and leaves streaks. Early morning or late afternoon is better.
Stubborn marks
- Bird droppings: soften with water first, then wash. Do not scrape.
- Oily or sticky marks: use a cleaner recommended by the panel manufacturer, tested on a hidden area first.
- Leftover protective film residue: this happens when film is left on too long after installation. Ask your installer before using any solvent.
What not to do
| Don’t use | Why |
|---|---|
| Thinner, acetone, petrol or other strong solvents | Can soften or strip the coating |
| Acid or strong alkaline cleaners | Can stain and dull the finish |
| Steel wool, scouring powder, hard brushes | Scratch the coating permanently |
| High-pressure jets on joints | Force water behind panels, damage sealant |
| Sharp tools to remove stickers or residue | Scratch the coating |
The annual inspection checklist
Clean panels are only half the job. Once a year, and before the monsoon, check:
Joints and sealant
- Cracked, shrunk or peeled weather silicone
- Gaps where sealant has pulled away from the panel edge
- Black streaks that suggest water running behind
Panels
- Dents, bulges or waviness (may signal a loose fixing or trapped water)
- Delamination at edges, where the skin separates from the core
- Chalking or fading, especially on west and south faces
Fixings and sub-frame
- Rust stains from screws, rivets or brackets
- Corrosion on the sub-frame where visible, especially mild steel frames
- Loose panels that rattle in wind
Top edges, flashings and openings
- Parapet copings and top flashings, where rain collects first
- Openings for signage, lights and AC pipes that were cut later and left unsealed
A simple maintenance calendar
| When | What |
|---|---|
| After installation | Remove protective film promptly; check all joints |
| Every few months (dusty roads, coast) | Rinse and light wash |
| Once or twice a year (inland) | Full wash |
| Before monsoon (April–May for Kerala and western TN; before October for the northeast monsoon) | Inspect joints, flashings, fixings; reseal where needed |
| After major storms | Visual check for loose or damaged panels |
Coastal and industrial sites
Near the sea or industries, salt and pollutants settle on the facade and attack fixings and frames. Wash more often, check fixings for rust more closely, and when renovating, use PVDF-coated ACP, corrosion-protected sub-frames and stainless steel fixings.
When to call a professional
- Sealant that needs replacement over large areas
- Panels that are loose, bulging or damaged
- Leaks appearing on internal walls behind the cladding
- Any work above ground floor height without safe access
Common problems and what they usually mean
| What you see | Likely cause | What to do |
|---|---|---|
| Black streaks running down from joints | Dirt washing out of ageing sealant, or water running behind | Clean, then inspect and reseal the joint |
| Panel looks wavy only in afternoon sun | Thermal movement with fixings too tight, or thin skins | Have the fixings and panel checked |
| Brown rust streaks below fixings | Corroding screws, rivets or mild steel frame | Replace fixings with stainless steel; treat the frame |
| Powdery white film when you rub the surface | Coating chalking from UV, common on polyester coatings | Clean gently; plan repainting or replacement in time |
| Damp patches on the inside wall | Water entering behind the cladding | Trace the leak from the top edge and joints downward |
| Edge of panel lifting or separating | Delamination of skin from core | Replace the affected panel |
Questions to ask before hiring a cleaning team
- Do they have safe access equipment and trained people for work at height?
- What cleaner will they use? Ask to see the product and check it is mild and suited to coated aluminium.
- Will they use pressure washers, and at what pressure and distance from joints?
- Will they report damaged sealant or loose panels they notice while cleaning?
Cleaning crews are often the first people to see a problem up close. Ask them to photograph anything unusual so you can have it checked.
How Cladex helps
Cladex Elevations installs ACP cladding across Tamil Nadu and Kerala. If your existing facade has loose panels, failed joints or leaks, our engineers can look at it on site and tell you plainly what needs repair and what does not. We look behind the panels where possible, because that is where long-term problems usually start.
WhatsApp us photos of your ACP facade for a free, site-measured quote.