A . Corresponding Editor Paul Fisette responds: I think that if your normal bleaching procedure accomplished what you want, then you should try to use a modified version of the same procedure indoors. First, wet-sponge the bleach solution (50/50 household bleach and warm water) onto the boards, and wait for the boards to lighten up. Then go over the boards lightly with a sponge that has been dampened with clean rinse water, instead of hosing the wall down. It would be a good idea to test this procedure in an inconspicuous corner of the room to be sure the result is satisfactory.
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