A garden shed can be a functional and attractive addition to your garden. A well-constructed and -maintained garden shed can last for decades. The key to shed maintenance lies in protecting the shed from sun, water and accumulated dirt and grime. Keeping a good finish on the shed and cleaning it periodically will greatly increase longevity.
Prepare the shed for finishing. Scrub the wood surface down with a good quality wood cleaner. Make sure the wood is completely dry before you apply any coatings to it. Surface preparation is key to the success of any finish applied to your garden shed. The wood should be clean, dry and free of any coatings that might interfere with the finish's ability to bond with the wood surface.
Select a finish. Assuming you are working with a wooden garden shed, you have a few different finish options. Transparent stains, semitransparent stains or solid colour finishes (paints) all seal the wood and protect it from both moisture and damaging UV rays from sunlight. Your choice of finish will depend on the look you are going for and the amount of maintenance you are willing to perform.
A transparent stain provides pigment for the shed's wood and seals it from moisture. The appearance of a transparent stain is such that it will change the colour tone of the wood, but it will not obscure the wood's natural grain pattern. The look of a quality wood stained with a transparent, oil-based stain can be strikingly beautiful. A transparent stain will last between 1 to 3 years before it requires another application. Longevity will vary depending primarily on exposure to sunlight.
A semitransparent stain is another one-coat, oil-based product. The pigments in the semitransparent stain are slightly larger than those in the transparent stains. A semitransparent stain will obscure more of the wood's detail, but the overall pattern of the wood grain should still be visible. A semitransparent stain should last between 2 and 4 years before requiring reapplication.
A solid colour finish, or paint, is a coating with a high amount of pigment. With proper surface preparation, a solid colour finish will provide your garden shed with 5+ years of protection before it will need to be reapplied. A solid colour finish is a multicoat product that completely obscures the wood's grain pattern.
Apply the finish of your choice. Make sure to follow the specific manufacturer's instructions for the finish you have selected. Transparent and semitransparent stains are generally one-coat products meant to penetrate completely into the wood's surface. A solid-colour product is a film-forming product, and typically two coats are applied over a primed surface. .
Keep the wood clean. Dirt, grime and mildew can compromise your garden shed's finish and cut into longevity. Periodically clean your garden shed. Wood cleaning products are usually sold in concentrated form. Follow the manufacturer's instructions depending on the type of cleaning you are performing.
Brighten the wood. Depending on the type of wood you have and the type of finish you are using, you may also want to use a wood-brightening product in order to neutralise tannic acids. These naturally occurring acids are prevalent in cedar and redwood and can dramatically darken the wood's colour.
Inspect the coatings. Keep an eye on the quality of the finish. With a penetrating oil stain, look for good colour and water resistance. Run a garden hose over the stained surface; water should sheet off. Water absorption is an indication that the shed should be restained. With a solid colour finish, look for signs of bubbling, peeling or lifting.
Refinish your garden shed when necessary. Any finish you apply will eventually need to be reapplied. To reapply a semitransparent or transparent stain, wash the surface down, allow it to dry and then brush, roll or spray on another coat of finish.
With a solid colour finish, generally more surface preparation prior to reapplication is necessary. Solid colour stains fail by lifting or peeling. Sand or scrape to remove the compromised coating from the wood's surface. After you've removed loose product, clean the surface with a wood cleaner. With the surface clean and dry, brush, roll or spray on two more coats of finish.
The greater exposure to damaging UV rays from sunlight, the more frequently you will need to refinish your garden shed. By placing the shed in a shaded area, you can dramatically increase the lifespan of the finish. Water is another component that breaks down finishes. Make sure your shed is furnished with proper gutters and downspouts. In addition, adjust sprinklers so that they are not hitting your shed.
Make sure to follow all manufacturer's warnings when using wood finishing products. Wood cleaners can be harsh and could burn your skin or injure your eyes. Wear long sleeves, long trousers and eye protection when working with wood cleaning and finishing products. Some oils used in wood stains can be subject to spontaneous combustion. Follow manufacturer's directions when disposing of rags used for application or clean-up of these products.