Interior Windows & Doors

Window frames and doors are most usually made of timber, metal or aluminium. Here’s how to clean, prepare and paint each type of surface.

Cleaning & Preparing

General Guidelines

• The first thing to do is to wash the windows and doors down with a warm water and sugar soap solution. Dirt and grease tend to build up around door handles and window catches especially. So be sure to give these areas a really good scrub
• If the paintwork is glossy, you might want to rub the gloss down to remove imperfections and create a slightly rougher surface for the new paint to stick properly. Rub down with 200 grit wet and dry abrasive paper dipped in water.

Timber

Previously Painted Timber In Good Condition

• If the timber has been previously painted, check to see if the paint work is in good condition. If it is, just rub it down with a rag dipped in methylated spirits. Then rub down gloss with 200 grit sandpaper.
• This is all the stripping you’ll need to do before filling and then priming
• Always prime previously painted timber with an oil-based primer unless you have totally stripped the timber bare.

Previously Painted Timber In Poor Condition

• Harder stripping will be needed if the previous paintwork is in poor condition (flaking, cracked, peeling, etc) or if the previous colour is much darker than the new colour
• Rub down gloss
• Replace or repair any rotted timber
• Prime bare patches of wood
• Fill gaps, cracks and nail holes with exterior wood filler (flexible filler)
• Give the surface a light sand. Try using a Masterflow® sanding sponge or wrap your sandpaper around a Masterflow® cork sanding block
• Remove any loose putty on windows, and replace with new putty
• Always prime previously painted timber with an oil-based primer unless you have totally stripped the timber bare.

Other Types Of Timber

• See Exterior Walls for information on how to clean and prepare other types of timber.

Metal (Iron, steel etc.)

• As with timber windows and doors, clean off grease with sugar soap, and get rid of mould (use either a moss and mould cleaner or a 3 part water to one part bleach solution). Use a nylon bristle brush
• Remove flaking paint
• Then use a wire brush or scraper to remove all loose mill scale, rust, paint, and other loose foreign matter
• Prime with an anti-rust primer.

Aluminum

• As above, clean the surfaces of grease, and mould. Use a nylon bristle brush
• Then make sure you thoroughly  clean off products applied with clean water
• Allow to dry
• Use wet and dry sandpaper to remove any corrosion. Sand it all down so that it is even and smooth
• Round off sharp edges on the edges of the frames and doors to allow better film build when painting
• If the aluminum hasn’t been painted before, or if you’ve just stripped back poor paint, apply a coat of a specified paint for aluminium (check with your paint supplier) before you top coat.

Painting

Type Of Paint

You need a good quality hard-wearing paint for windows and doors. Try a water-based enamel (gloss or semi-gloss). It’s easy to wipe clean and much faster drying than a solvent-based paint.

Best Applicators For The Job

Windows

For painting windowsills and frames we recommend using a Masterflow® Angle Trimmer brush. The angle lets you control where the paint goes and is easier than painting with a straight edge

Doors

• For doors with a smooth surface we recommend using a smaller roller 75mm. But don’t forget to match the right roller to the paint you have chosen. Use the PAL® Roller System.
• For doors with glass inserts or surface designs brushes may provide the best result and we would recommend using a Masterflow® Angle Trimmer brush around the edges.

Handy Hints

• Whether you’re painting windows or doors, always paint from the top down.

Windows

• Your first step when you start painting is to either cut in around the glass with a cutting in brush, or mask the glass.
• Then use a small trim brush to paint muntons (the dividers in the window). Start at the top and work down, painting both the vertical and horizontal dividers.
• Then paint window surrounds.
• Make sure you work from top down and wipe off drips before they dry.
• Lastly, paint the face trim around the window using an angled trim brush.

Doors

• Paint the edges first then apply paint to the face of the door, starting at the top.
• If the door has a moulding, or raised inset panels, paint the mouldings and inside the panels first. Then do the remainder of the panels and door surface. If the door has a threshold, do that last.