Priming New Cedar Siding

Hardboard siding may also require a primer.

Priming new cedar siding.

Allow it to dry for the amount of time specified on the instruction label. Apply one even thorough coat of water repellant preservative to the cedar siding with a paint brush or roller. Water borne primers cannot block the tannins in the cedar. First remove any mill glaze a hard shiny surface on one side of the siding by sanding.

If you do not intend on priming brand new cedar or redwood for that matter a high quality stain paint should be used as 50 of volume soaks into the wood other 50 is left on top as a dried paint mil. This stain covers all wood grain completely and gives the wood an appearance of being painted. Stains dry rapidly and fresh stain applied over dried stain will show lap marks. Priming western red cedar helps the wood s natural properties stay put.

The only way to block the tannins in the cedar siding is to use an oil primer. Without a primer tannins from within the cedar mix with moisture and seep to the wood s surface naturally staining and discoloring the surface. Staining cedar siding differs from application of paint and other finishes. If possible stain all sides of the siding before installation.

As a general rule use an alkyd primer and a latex topcoat when repainting. Properly primed a 100 percent acrylic latex paint will provide decades of protection for cedar siding shingles. What that means is that you can put primer on the cedar siding but brown stains will come through. Do not use water borne primers over exposed cedar siding.

These paints form a tough but flexible film that allows moisture within the wood to escape while protecting the cedar from atmospheric moisture that might lead to extractive bleed. According to paul mackie at the western red cedar lumber association wrcla red cedar siding that has been finished on all six sides with a stain blocking primer and top coated with 100 percent exterior acrylic latex paint has the longest expected service life of any coating system.