How do I clean cedar siding?

When it’s not time for repainting or staining, you can preserve the life of your finish with a regular annual cleaning of your cedar wood siding. Inspecting and cleaning your siding on a regular basis will help protect it from staining, splitting, and moisture damage that come from seasonal changes.

Dirt is commonly found to be the greatest contributor of discoloration to cedar wood siding. You can clean dirt from your cedar siding by simply using warm, soapy water and a soft-bristled brush. Making sure your siding is free of dirt and mildew will help ensure the longevity of your cedar wood siding.

Here’s a very quick how-to clean wood siding:

When cleaning wood siding, work in smaller 10’x10’ sections. Start at the top of the wall and work to the bottom. Never allow your cleaning solution to dry to the wall, so, make sure to rinse frequently once each section of siding is completed.

Also, when you are ready to get to cleaning your cedar wood siding, make sure to turn off the power to any outside lights or power outlets that you may come in contact with during the clean; and make sure all of the windows are properly closed. Oh, and spray away from doors and windows - not towards.

Restoring cedar wood siding’s color

Natural cedar wood siding that has discolored due to age can be restored back to its original color by using a wood cleaner or brightener. These types of products are often purposed for use with cedar wood decks, but they also work well on natural cedar wood siding.

How to clean mildew off cedar wood siding

When mildew appears on cedar wood siding, it shows up as tiny, black spotted staining. Use a rag and dab the area with some diluted bleach, if the black spots disappear, it’s most likely mildew. In order to clean mildew from your cedar wood siding, simply use a solution of 1 part bleach to 4 parts water. Scrub the areas with a soft-bristled brush, and make sure to wear proper eye and skin protection. When using bleach solutions, don’t forget to protect any of your beloved garden plants from coming into contact with your cleaner. Afterwards, rinse thoroughly with your garden hose.

How to clean the rust off cedar wood siding

Another commonly found stain on your cedar wood siding is rust. Rust stains will appear as dark black stains and vertical streaks. Rust stains are most often the result of ungalvanized fasteners used to affix the cladding or other items attached to the cedar wood siding. In order to remove a rust stain, dissolve 4 oz. oxalic acid in 1 cup warm water and apply the solution directly to the stain by gently scrubbing with a soft bristle brush. When done, thoroughly rinse the area with your garden hose. Again, safety first! Make sure to wear proper eye protection, acid-proof gloves, and certainly avoid spilling the solution onto adjacent surfaces.

Power-washing cedar wood siding

When using a power washer, a lot of care needs to be taken or you run the very real risk of seriously damaging your cedar wood siding. The forces power-washing generates easily strips the paint, carves out gouges in softwoods, blows out caulking, and even forces moisture through painted surfaces!

If this is your preferred attack, avoid upward angles, as that will force the water beneath your cedar wood siding. Begin spraying with the nozzle pointed away from the cedar wood siding, slowly bringing the tip towards the wall, making sure to not get closer than 12” from the cedar wood siding, and away from windows or damage may occur. Always use both hands when operating a power washer, and never use it while on a ladder. If cleaning is necessary beyond the first floor, and a ladder is required, using the soft bristled brush approach is your safest bet.

The best technique when power washing is to go the full horizontal length of the siding board, not vertically from course to course. Spraying in a vertical pattern will cause a visibly inconsistent pattern which will be undesirable and very difficult to overcome.

In closing, if you suspect that your cedar wood siding may have been painted with lead paint in the past, you risk spreading lead paint flecks throughout the area and can negatively affect your children and your pets, and would be best served to wash it by hand and hose.

Cleaning your siding and staying on top of annual inspections helps you to avoid more costly repairs for your siding. It’s easier to replace a few damaged pieces of cedar wood siding when required, than to try to reclaim the days past after years of neglect. Cedar wood siding is beautiful and can last for many decades with the proper care and regular maintenance.