Creosote is a compound common found built up inside chimneys of wood-burning stoves and fireplaces. Although most creosote accumulates in the chimney, it can also build up on your composition roofing shingles. As the ash comes out of your chimney, the air can carry it along your roof, where it will settle on your shingles over time. If you're seeing signs of black stains along your roofing shingles, particularly in the area of your chimney, that's a sure sign that you have creosote built up. It's important to clean your roof before and after your burning season to prevent serious damage.
Why is Creosote a Problem?
Creosote is a highly flammable substance, and it is to blame for the vast majority of chimney fires across the country. The last thing your roof needs is a layer of something this flammable covering its surface. One spark or errant hot ember from your chimney can set the whole thing ablaze if you don't keep it clean.
Who is at Risk of Creosote Buildup?
If you're burning a woodstove or a fireplace, you're going to have creosote. It's formed from the residual byproducts of the fire. In order to avoid a dangerous level of creosote buildup along your roof, you'll have to keep it clean. You can call a roof cleaning contractor if you prefer, but you can do the work on your own with the right supplies.
What Do You Need?
If you decide to tackle the cleaning project yourself, you'll want to make sure that you have everything you need ready before you get started. Drop cloths will be beneficial for covering your shrubbery and landscaping along the edge of the house. You'll also want to have protective wear such as gloves, goggles and dust mask for your face.
To create the cleaning solution, you'll need a bucket, oxygen bleach liquid or powder, a measuring cup and a wooden stick to mix it with. Make sure that you use oxygen bleach, as chlorine bleach may cause damage to the surface of your shingles.
Finally, you'll have to have a ladder to get to the roof and a hand-pump sprayer that you can use to apply the solution.
How Do You Clean the Roof?
Spread the drop cloths out over the landscaping and border shrubs planted around the outer edge of the house. This will protect your growing plants from any bleach splatter or creosote. Put on your protective gear before you start mixing the cleaning solution so that you are protected from the dirt and debris.
Mix a cup of oxygen bleach into each gallon of warm water, then stir it to make sure that it is well-blended. If you choose a liquid oxygen bleach, this won't be as difficult, but if you choose a granular oxygen bleach product, you'll want to be attentive to how well it dissolves. It needs to be thoroughly dissolved before you use it.
Place the ladder firmly against the house in the area where you want to clean. If you're going to clean the whole roof, start at one end and work your way around. Put the bleach cleaning solution into the sprayer and secure the lid. Use a hand-pump sprayer, not a pressure washer. The force behind the water from a pressure washer can damage the granules on the surface of your composition shingles, which can cause more damage to the roof.
From a secure perch on the ladder, spray the bleach solution onto the areas of the roof that you need to clean. Make sure that cover the area thoroughly. After about fifteen minutes, fit a low-pressure spray head to your garden hose and rinse the roof area thoroughly. Let it dry completely after rinsing. It may be best to do this on a sunny day so that the heat from the sun can help the shingles dry.
If you aren't comfortable doing this on your own, talk to a roofing contractor about cleaning the roof for you twice a year. This will prevent any dangerous buildup.