More in Painting
Paint or a natural wood preservative finish are essential for exterior woodwork because it is prone to damage from the elements. Maximize protection by using hardwearing fillers and exterior-grade paints. Problems can still occur. The heat of the sun can cause sap to bubble out of knots, blistering the paintwork. Use a heat gun followed by knotter to prevent further damage. This technique can also be used on bare wood, prior to painting. Small cracks in paintwork can lead to minor rot problems. Pellets of wood preservative or wood filler repair are an excellent way to repair rot damage. Large areas of rotten wood need to be replaced.
Wooden siding is treated like any other exterior woodwork, but it must be washed down thoroughly in order to remove all signs of dirt. In some circumstances, fungicide may be required, which can be applied as shown for masonry walls.
Scrape all the sap and excess paint away from the affected area (Image 1).
Use a heat gun to heat up the sap so that it bubbles out from the knot. Keep using the heat gun until the sap stops flowing (Image 2).
Sand the area to remove residue and provide a clean, smooth surface for painting (Image 3).
Apply sealer to the knot using a small brush. Once this is dry, you can prime and paint the area using exterior-grade paints (Image 4).
Scrape the rot back to sound wood (Image 1). Allow the area to dry out, then apply wood hardener to the exposed wood.
Use a two-part wood filler specifically for exterior use to repair the damage caused by the rot (Image 2).
Drill holes around the rotten area. (Drill bit size will be specified on pellet packaging.) Push pellets into the holes, making sure they sit below the wood surface (Image 3). You can then fill the holes with more exterior filler. Sand the treated area smooth before priming and painting. Like many preservative products, pellets contain toxins, so be sure to wear gloves when handling them.
Wooden windows and external doors rely on paint or a natural wood finish for protection. Start work early in the day so you can close the windows and doors before night. Apply paint using the technique specified for wood.
Cracked puttywork can let down the finish of an otherwise well-painted window or glazed door. As long as the putty is sound, fill it with an all-purpose filler, then sand and paint with the wood. Take care not to allow the sandpaper to touch the glass surface, because it will scratch it. Where putty is very loose or missing, remove as much as possible, dust away any debris and re-putty.
Take the door off its hinges. Apply preservative primer to the top and bottom edges of the door (Image 1).
Prime and paint the edges when the preservative primer has dried using exterior paints (Image 2).
Vinyl doesn't require painting. It can be kept bright and clean with a non-abrasive cleaner. Some cleaners denature and degrade rubber seals or gaskets, so check the manufacturer’s guidelines. When painting surrounding wall surfaces, take care to mask up vinyl as removing any paint overspray can be very difficult.
Metal windows or parts of windows are often factory-coated and so don't require painting. Old metal windows can be painted using much the same system as normal wooden windows, except that an appropriate primer must be used to prevent rust damage.
Excerpted from Do It Yourself Home Improvement
© Dorling Kindersley Limited 2009