Fir has a light rosy color that darkens with age when exposed to sunlight. To preserve the natural vertical wood grain colors in fir, select oil-based stains that penetrate beneath the surface of the wood. Oil-based stains are an effective stain option for fir because the oily composition soaks into the fibers of the wood. Due to the stain-resistant nature of some types of fir, for example Douglas fir, the wood needs to proper sanding before applying any stain. Oil-based stains protect against weathering, discoloration and fading but take time to dry. Oil-based stains are durable and they maintain a uniform finish requiring little maintenance.
If you have a piece of fir furniture unsealed with a permanent finish, select a semitransparent stain. Semitransparent stains come in a variety of colors that harmonize with fir wood grains. Apply semitransparent stains over bare natural fir to encourage the natural wood grains to show through after the stain application is completed. Semitransparent stains are not recommended on outdoor fir furniture because the stain does not soak deep enough into fir fibers to protect it against harsh weather elements.
Gel stain is a one of the most suitable stains for fir. Since fir is somewhat resistant to staining, gel stain works well because it rests on the wood and slowly seeps into the wood grain. Sand your fir furniture before you apply gel stain to ensure long-lasting adhesion. Allow sufficient time for the gel stain to penetrate the surface of the wood and keep the furniture in a moisture-free area until the stain completely cures.
Select a latex stain for fir furniture if you want a thick durable stain that is suitable for the outdoors. Even though re-staining over previous stain is not advisable, if you need to cover over an old oil-based stain and don't have the time or the necessary tools and chemicals to remove the old stain, a latex stain works best. Latex stains are weather-resistant and are not prone to fading. Due to the adhesive qualities in latex stain, it is the best choice for a wood like fir that is resistant to rot. Avoid latex stains on bare fir if you don't want the stain to darken or discolor the natural beauty of untreated fir.