The Best Type of Primer Paint for Exterior Wood

Acrylic-Latex Primers

• An acrylic-latex primer is ideal for most exterior wood siding. It's a breathable finish that expands and contracts with the wood's expansion and contraction. That means it bonds tightly to the siding as the seasons change. An acrylic-latex primer outperforms a latex primer at blocking stains and provides better adhesion to new lumber. It's fast drying time makes it common with weekend do-it-yourself painters. This primer class is a good choice for soft woods, such as pine and fir, when a latex or acrylic latex primer is later applied as the finish coat.

Alkyd Primers

• Alkyd primers are a good choice for blocking tannins in woods, such as cedar or redwood. These primers do a better job of sealing exterior wood for homes in high-humidity climates, and they prevent bleed through of wood resins, rust from nail-heads, and marker or graffiti stains. Alkyd primers also form a solid bond to chalking paint. Alkyd primers are often recommended for spot priming over nail heads on new construction preventing eventual rust bleed through. Apply alkyd primer over existing latex or alkyd paints.

Shellac Primer

• White-pigmented shellac primers are usually limited to indoor use, but are traditionally seen as the best choice for preventing resin bleed through from knotty portions of pine and other woods. Shellac is not suitable as an overall outdoor primer because it becomes brittle under temperature extremes. Shellac is usually applied as a spot primer. Depending upon weather conditions, it is ready to paint over in three to four hours, and it accepts latex, acrylic-latex or alkyd primers.

Peel-Bonding Primers

• The siding on many older homes is covered with multiple layers of oil-based paint that now appears uneven because some of the older coats have peeled off. The best choice is stripping all the damaged paint off the wall, but that takes much time and expense. Instead, use a peel-bonding primer. These primers go on thick enough to fill in the voids and level out the surface for the next coat of exterior paint.