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lot of people still love wood siding and shingles even though the expense is rather high when compared with other exterior sheathing materials. Unfortunately that new look won’t last forever because the Sun’s UV light, rain and snow and other conditions can break down the fibers and bleach the wood. Some people enjoy the look of bleached siding but there are options if you want to keep your home looking fresh.
The first thing you should understand is that you don’t want to apply any paint or clear products to the wood that will seal it off completely. Paint and Varnish or Polyurethane will create a skin over the wood but as humidity and moisture works its way through the back of the untreated wood or even through cracks in the paint then the paint will begin to fail and flake. This is why if you want to use a product on your exterior wood surfaces it is normally best to use a breathable product that will allow some moisture to pass through it. There are some situations where Paint or Polyurethane is appropriate but that is mostly limited to outside furniture which will be protected with a tarp or brought inside during winter months.
If you don’t use a stain or sealer on your wood as soon as it is put up then it will start degrading from UV Light and weathering. Some people like that and others think it looks like crap. I personally think it looks like the owner isn’t taking care of their property. You can end up with some nasty uneven stains from water running off the roof or around windows and especially at ground level. At that point if you change your mind you end up trying to bleach out these stains before you can apply a clear preservative or you have to use a solid stain to cover the staining. Whatever you attempt to do after there has been weathering will never result in as good a finish as if you acted when the wood was applied to the building.
When contractors are shingling a home they will normally apply the sealer to all sides of the shingle or siding board by building a dipping trough. It is then filled with gallons of stain or sealer and the wood is dipped into it and then removed and placed on a drying surface often with nails that support the wood or stacked in a way that they won’t stick to each other or the drying surface when the stain drys. This way a lot of product can be processed quickly and you are sure to get every side of the material treated.
Treating material that has already been installed can be done with a sprayer and then back brushed after. Back brushing is when another person follows the person with the sprayer and brushes it into the surface and all the areas that might have been missed. It is very important to back brush stains and sealers because spraying alone can result in drips, spotting and uneven application.If you don’t have two people to do the job then you will have to work slow enough that you can back brush before the surface drys. For this reason you never apply stain or sealer in direct hot sunlight.
Another consideration is the moisture content of the wood. It is best to not apply stain right after a rain and the surface can be checked with a moisture content meter to make sure it is dry enough to accept the stain without problems. Problems could mean early failure of the stain or sealer because it does not penetrate deep enough into the wood. If you have to pressure wash the wood before applying stain then you will have to wait a number of days before you apply the stain or sealer for it to dry fully. The best wood is very low moisture content 12% or less and it will suck up the stain or sealer deep into the wood.
Which Is Best Sealer, Semi Transparent Stain Or Solid Stain?
The choice of what type of product to apply to your exterior wood surfaces can be tough to make. Many people love the natural look of wood and if you do then a sealer is probably your best choice as it will just preserve the wood and not change its color. If you materials have a slightly uneven look then a semi transparent stain can help make it more uniform and it can also add a tone to the wood to slightly change its color. This is a great choice for decks made of pressure treated lumber that you want to make look a little more like a hardwood and still see some of the natural grain through the stain. Solid Stains act pretty much like paint and will give you a surface that looks painted but will stand up much better to weather. Solid stains are also a great choice for older weathered wood that you want to restore and make look new. Simply ask your paint supplier to match the color of a natural piece of wood. They will scan the wood and then the paint mixer will produce a color that is very close to natural wood color although it will only be a single color so it won’t look exactly like natural wood that has many changes in tone it will be surprisingly nice from a slight distance and look like new wood.
Should Wax Based Sealers Be Used On Siding?
Many people debate wax vs oil based sealers when it comes to treating exterior wood products. The main thing about using a wax based product is that it will embed into the wood and cover it with a coating that won’t accept new stain. This can be a serious problem for people that want to later treat older siding or wood with stain to restore its fresh look or who want to change the color of the wood by applying a solid stain. The option can be to sand the surface to remove the wax but you have to go deep enough that you remove all of it.
Unfortunately once you go with a waxed based sealer there isn’t really a chance to go back to an oil based sealer or stain. This can be ok on utility sheds and other out buildings if you don’t ever expect to stain them but for the most part it is recommended that you don’t use wax sealers when the wood is early in its life and reserve them for when the wood is nearing its replacement age.
Also the life of the product between treatments will increase based on how much solid materials are in it. A clear oil based sealer will have to be applied every 1 to 3 years a semi transparent stain should last to about 5 years and a solid color stain should last to about 10 years. The rating and warranty on the products should tell you more details but basically the less you can see through the product means the less UV Light can degrade it.
Final Note
It is important that you understand the proper and normal use of Stains, Paints, Sealers and other products that you apply to exterior wood surfaces and the best practices for each product.
For the most part stain and oil based sealer are the best choices for exterior wood products. Oil Based Sealers are manufactured by the same company that makes the Stain and it is just a product that has no solids or pigments so its the stain without the color. If you stay within this range of products you can go back and change colors or apply new tones later.
Waxed Based Sealers might be good for any type of building, fence or other wood items but you have to remember that the wax will embed into the wood and then staining and sealing is not really an option unless you are willing to sand the entire surface and that normally only works on older wood vs freshly treated wood.
Ask your paint supplier for more information but treating you wood shingles and siding when you install them will extend their life and will probably result in a better appearance overall.