Preparation is key to successfully painting your wood siding. If your existing siding is in good shape, the only preparation that you might need to do is washing it thoroughly. If your existing paint happens to be peeling and cracking, you’ll need to remove it so that the surface is smooth, flat, and free of the failing paint.
When you begin to hose down your siding, you’ll want to be cautious not to force water between your siding boards and into the joints. In some situations, you are able to use a power washer but you’ll want to be extremely careful that in addition to not driving water between the siding boards, you aren’t eroding your wood’s surface with its forceful blast.
Note that washing your wood siding alone is not enough to remove mildew and mold from the surface. If you are experiencing mildew or moisture issues, you may want to think about getting your siding replaced.
In order to remove chipped paint and ensure an even painting surface, you’ll want to smooth down the edges of any scraped areas. A power sander can be used. For bigger jobs, if you are sanding down your entire home’s siding and not just a small area, a commercial-grade seven-inch sander is recommended. These are available at your local home improvement center or you can rent one at an equipment rental company.
Sanding is completed in two stages. First, the paint cover needs to be removed. It is recommended to use coarse 60-grit sandpaper for this task. This will leave cuts in the wood so it’s important to follow up with a medium 100-grit sandpaper to ensure a smooth surface.
Keep these in mind when using a high-powered sander:
For all of the areas that your power sander cannot reach, such as corners and tighter spots, use a scraper. Use the scraper with two hands to avoid gouging the wood. If you do happen to experience gouge marks, sand the areas down and fill them with a vinyl exterior spackle to prevent them showing through the new paint job. Make sure to sand down any rough edges from the scraper with coarse sandpaper.
Upon completing all of the above steps, you are ready to prime and paint. Dust off any sawdust and remaining debris and caulk any visible openings and seams. You’ll want to prime your bare wood with a latex primer that is tinted towards your finished color. Allow your primer to dry thoroughly before you begin painting.