During rough-in stage, minimal preparation is required. Electrical outlets, plumbing penetrations, bathroom/ kitchen vents, etc should be covered. The sealant will not stick to vertical surfaces, so there is no need to cover windows or walls. After rough-in, the sealing will produce a thin layer of sealant on horizontal surfaces that can be removed with everyday household cleaners. Any finished horizontal surfaces need to be covered and any large intentional openings (e.g. exhaust fan ducts) need to be covered manually.