Also prime the ends of adjoining boards. This step pays off by slowing the moisture penetration that can lead to peeling at the joints. If the new siding is redwood or cedar, buy a special “stainblocking” primer. Both of these woods contain natural chemicals (tannins) that can bleed through paint, causing brownish stains. A stain-blocking primer will seal in the tannins.
Use a wire brush and a wide-blade putty knife to remove small areas of defective paint. Scrub under the laps of clapboard siding as well as on downspouts and gutters. For speedier work on metal, a wire brush attachment on an electric drill will remove rust and paint with less effort. For more extensive paint removal, invest in a sharp pull scraper -- a tool with a replaceable blade that's capable of stripping old paint all the way down to bare wood with a single scrape. Hold the scraper so the blade is perpendicular to the wood, apply moderate to firm pressure, and drag it along the surface. Keep the blade flat against the wood so it doesn't gouge the surface.
A number of factors help determine when you should paint your home’s exterior. These include your local climate and weather conditions, the age of your home, and the type of siding used. A high-quality finish in ideal conditions could last 10 years. But if your home takes a beating from the elements, you may need to repaint as often as every three years. Most homes can be on a 5-8 year interval. If you’re not sure if your house is due for a refresher, watch out for signs of deteriorating paint, such as fading and chipping.