Heat stripping is the removal of old paint or varnish layers by warming them with a heat gun until they soften, then scraping them off with a paint scraper or filling knife. It is a widely used method when renovating timber window frames, doors and cladding.
How does heat stripping work?
The heat gun blows air at 300–600 °C onto the paint surface. The paint softens and lifts from the substrate. A broad scraper or filling knife is then used to peel the softened paint away.
Step by step:
- Heat — hold the gun about 5 cm from the surface and move slowly
- Scrape — as soon as the paint blisters or wrinkles, scrape it off
- Sand — after stripping, lightly sand the timber for good adhesion of the new coat
Application
Heat stripping is used on:
- Window frames — removing multiple old paint layers during renovation
- Doors — stripping back to bare timber for a fresh finish
- Cladding — weatherboarding, featheredge boards and fascias
- Staircases — old paint on timber stairs and balustrades
- Mouldings — cornices and architraves cleared of old paint layers
Advantages over other methods
- No chemicals — unlike chemical paint strippers
- Less dust — compared with sanding
- Fast — thick paint layers are removed efficiently
Safety notes
- Fire risk — keep combustible materials clear; do not use near roofing felt or insulation
- Lead paint — buildings from before 1960 may contain lead paint; take precautions
- Glass — protect glass from the heat, as it may crack
Related terms
- Decorating
- Window frame
- Maintenance
- Sanding
- Timber
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