How to Lighten Dark Cedar Siding
- 1). Find out whether mildew is the cause of the discoloration by applying a small drop of household bleach to the wood. If the area becomes lighter immediately, you are dealing with mildew.
- 2). If this is the case, wash all the cedar with a mixture of 1 part bleach to 3 parts water, and scrub with a plastic brush.
- 3). Rinse the wood quickly with clean water, as leaving the bleach on the wood for too long can cause damage.
- 4). If mildew is not the problem, wash the cedar with wood cleaner, be sure to follow the instructions on the packaging. Check the cedar every 15 minutes to ensure that the dirt is being removed while leaving the cedar unscathed. Scrub with a nylon or plastic brush to remove all dirt.
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