Western red cedar used indoors for panelling, posts, beams and joinery requires less protection than exterior siding, trim and decks and consequently different types of finishes are used. The exception to this general rule is when the western red cedar may be subjected to high moisture levels, for example in bathrooms. In such situations, finishes should be exterior grade, and have good resistance to moisture. Always ensure that the coating is recommended for interior use.
Most people selecting western red cedar for use indoors will want to retain its natural appearance. This is best achieved using transparent finishes such as waxes, shellack and other clear film forming finishes. These “interior” finishes provide some protection to the cedar from minor abrasion and liquids (less so with wax) and make cleaning easier.
Western red cedar used indoors can also be coated with a variety of finishes. For example, bleach, oils, semi-transparent and solid body stains and opaque finishes can be used to change the wood’s appearance to complement a decorative theme. We have a complete list of suitable interior products in our indoor finishing types section. This section, however, will focus mainly on finishes that enhance the natural appearance of cedar and have a minimal effect on indoor air quality.
To achieve the best results, the wood should be preconditioned in the area of the building in which it will be used, prior to installation. This will enable the cedar to achieve equilibrium moisture content with its surroundings. Western red cedar, depending on its texture, may require a light sanding with fine-grit sandpaper to remove any minor surface characteristics. It is good practise to experiment with the proposed finish on a small sample of wood identical to the product to be finished. This will ensure that the coating will achieve the desired “look.” Once the decision has been made about the type of finish, the same brand name product should be used throughout to avoid incompatible formulations and colour variations.
The rich beauty of western red cedar’s natural colour can be enhanced or modified by applying any of a number of commercial finishes. If left in its natural state, some darkening of the wood can be expected as it ages and the colour variation will become less pronounced. Application of transparent finishes will also darken western red cedar to some degree but they form a protective surface that is easier to maintain.