Do I need to spot test Universal Cleaner first?Updated 9 hours ago
TL;DR: Yes. Always spot test Universal Cleaner in an inconspicuous area before using it on any new or unfamiliar surface. Particularly important on natural stone, sealed timber, soft metals, and soft furnishings. Three quick steps, a few minutes, peace of mind.
Last reviewed: April 2026
Why do I need to spot test Universal Cleaner?
Universal Cleaner is alkaline (pH 12.5). Most hard surfaces handle it fine, but materials like untreated natural stone, aged timber sealants, soft metals, and some delicate fabrics can react. A 5-minute spot test catches any issue before you apply it to the full surface. Best for peace of mind and protecting valuable finishes.
✓ Always spot test
Natural stone (marble, granite, travertine, limestone). Sealed timber. Soft furnishings (carpet, upholstery, leather). Any vintage, aged, or unusual finish. Any surface you're unfamiliar with.
⚠ Known incompatible
Soft metals (zinc, copper, brass) will discolour. Raw aluminium will oxidise. Aftermarket window tints can peel. Skip the spot test and avoid these surfaces entirely.
How do I spot test Universal Cleaner?
Pick a hidden corner or edge (the back of a cabinet, underside of a chair, hem of upholstery, closet floor). Spray a small amount of Universal Cleaner, let it sit for a few minutes, wipe clean. Check for any change in colour, sheen, or texture before cleaning the rest of the surface.
✓ Three-step spot test
Pick a hidden spot. Back of a cabinet, underside of a chair, hem of upholstery, closet floor, or any corner that won't show if something goes wrong.
Spray a small amount onto the hidden area, wait a few minutes for the alkali to have full contact time, then wipe clean with a microfibre cloth.
Check for changes. Look for colour loss, discolouration, sheen change (matte patches on glossy surfaces), etching, softening, or texture change. If clear, proceed to the full surface.
What should I look for during a spot test?
Changes can be subtle. Look for colour loss or lightening, darkening or staining, sheen changes (matte patches on a glossy surface or vice versa), etching or pitting on stone, softening or stickiness on sealants, or visible texture change on fabric. If any of these show up, stop and reach for a more surface-specific cleaner.
⚠ Warning signs to watch for
Colour loss or darkening. Sheen change (matte patches on gloss, shiny patches on matte). Etching or pitting on stone. Softening, stickiness, or tackiness on sealed surfaces. Fabric texture change. Any discolouration on metals.
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