Identify the surface and follow the current instructions for your exact products. Do not sand or strip uncertain old coatings. Read the safety guide before disturbing materials.
Find out what is already there
A greasy door, bare timber and a sound painted skirting need different preparation. Older paint may contain lead, so establish that the surface is safe before scraping or sanding. Thin veneers and moulded door skins need gentler treatment than solid timber.
Clean first, following the cleaner’s instructions and rinsing where required. Sanding grease into the surface makes adhesion worse. Let the surface dry fully before further preparation.
Keep the shape, improve the surface
On safe, sound painted woodwork, the goal is usually to remove nibs and provide the preparation specified by your paint system, not to remove every old layer. Avoid rounding sharp profiles or sanding through thin edges.
- Remove or protect handles and protect adjoining surfaces.
- Clean, dry and make suitable stable repairs.
- Abrade only as required and remove dust thoroughly.
- Prime bare areas, knots or difficult surfaces using the specified system.
- Apply thin, even coats in a logical order along the panels and grain.
- Keep doors separated from contact points until sufficiently cured to avoid sticking.
Give trim paint time to harden
Touch dry does not mean ready for scrubbing, tape or a tightly closed door. Water based trim coatings can take considerably longer to reach their intended hardness than to accept a second coat. Follow the manufacturer’s curing advice.
Check the work in side lighting while the paint is still workable, then leave it alone. Repeated brushing as the coating starts to set often increases drag marks.
Common mistakes
- Putting water based trim paint directly over an unprepared glossy coating.
- Leaving dust packed into corners.
- Closing painted doors tightly before the finish can tolerate contact.
Suspected lead paint, timber decay and damaged fire doors require suitable specialist advice before alteration or stripping.
Sources & further reading
Original general guidance from Aethos, informed by the resources below. These references cover relevant safety, materials or techniques, not a specification for your property. Product examples are not paid recommendations.
- HSE: lead in construction (opens in a new tab)
Why disturbing older lead paint requires a planned, controlled approach.
- Zinsser: Bulls Eye 1 2 3 technical information (opens in a new tab)
An example of why preparation, substrate suitability and recoat instructions are product specific.
- Farrow & Ball: paint finishes (opens in a new tab)
Different products and sheen levels for different surfaces. Check the current product advice sheet.