What surfaces should I avoid using Universal Cleaner on?Updated 3 days ago

Koh Universal Cleaner is alkaline at pH 12.5, which is strong enough to cut through grease but reactive with a small number of materials. Avoid raw soft metals: raw aluminium, copper, brass, and zinc can discolour, tarnish, oxidise, etch, or develop a cloudy film on contact. Avoid aftermarket window tint films and protective window films, which can peel, cloud, or lift at the edges. Avoid factory-applied or aftermarket easy-clean glass coatings such as ShowerGuard, Diamon-Fusion, ClearShield, EnduroShield, or similar hydrophobic glass treatments, which can strip. Also avoid wool and untreated natural fibres. These reactions are chemical, not a cleaning product defect, and any alkaline cleaner will produce the same result. Sealed, lacquered, or coated versions of these metals are usually fine but should be spot tested first to confirm the protective layer is intact.

No. Avoid Koh Universal Cleaner on aftermarket window tint films (car windows, privacy films), protective window films, and factory-applied or aftermarket easy-clean glass coatings (such as ShowerGuard, Diamon-Fusion, ClearShield, EnduroShield, or similar hydrophobic glass treatments). These coatings can peel, cloud, lift at the edges, or strip when exposed to alkaline cleaners. Factory-installed automotive tints are usually more robust than aftermarket films but still worth checking with the manufacturer before using any alkaline cleaner. Always follow the manufacturer's cleaning guidelines for coated glass and treated surfaces.

Spot test. There are too many specialty finishes, manufacturing coatings, and vintage materials in modern homes to list every incompatible surface. If a surface is unfamiliar, unusual, or valuable, spray a small amount of Koh Universal Cleaner on a hidden area, wait a few minutes, wipe with a Koh cloth, and check for colour change, sheen change, etching, or texture change before committing to the full surface. Five minutes of testing beats a damaged surface. Spot testing is especially worth doing on natural stone, aged sealants, soft furnishings, and anything labelled as a specialty finish.

Universal Cleaner Starter Kit

Pairs a box of Universal Cleaner with Atomiser Spray Bottle and Universal Cloths. Everything you need to start.

Universal Cleaner

2L bag-in-box refill. 20+ cleaning jobs around the home. Most surfaces, most homes, no fuss. Spot test the tricky ones first.