Ralph writes from Waterford, Michigan: "I purchased this house flat-ranch on a slab the vaulted roof does not have a ridge vent or rafter or eave vents on the house the drywall on the inside is screwed right to the rafter I noticed the roof to be spongy in spots I want to know where to install the rafter vents and should this correct my problem also the previous owner just had the roof done so I don't. want to tear off the shingles if I don't have to."

Answer: I am not so sure that adding Raft-R-Mate® rafter vents will solve the problem of soft spots, but Raft-R-Mate rafter vents are installed right under the roof deck with gaps between the pieces to allow moisture to travel into the airspace you are creating. Venting needs to be installed at the soffits and at the ridge or peak of the roof.