Q: I have built some furniture of clear pine and like the natural color of the new wood when freshly sanded. If I coat it with polyurethane, it yellows and darkens the wood; if it is left raw, it darkens with age. Is there any way to maintain the raw look of freshly sanded wood?
A: Any finish will darken the wood to some extent -- it is just a matter of degree. Experiment with different finishes, but expect some darkening with all. As a rule, clear lacquer and clear shellac will darken less than a varnish or penetrating sealer.
Q: I live in a 70-year-old house that has a chimney going up through the center. During the last two winters I have noticed that the base of this chimney is very damp and the paint is peeling off on the inside. There is no door at the base of this chimney. Can you tell me what the cause of this can be and what I can do to remedy it?
A: Moisture is getting into the chimney structure from outside, and since the chimney runs through the center of the house it must be that the moisture is entering from somewhere near the top in the section that sticks up above the roof. First, check the concrete chimney cap at the very top. If this is cracked (or missing in places) the cement should be patched to keep water out. Then check the flashing where the chimney comes in contact woth the house walls on the outside. Finally, check the mortar joins in the brickwork -- they may need tuck pointing.
Q: We are planning to insulate the attic crawl space in our house before next winter. It has no insulation now. The opening in the ceiling through which we must go to reach into this crawl space is rather small, so we plan to unroll the insulation batts down below, then pull them up to make things easier. Would it be just as effective to use two layers of 3-inch-thick batts as one layer of 6-inch-thick material and, if so, should the vapor barrier of the top layer be facing the same way as the one on the bottom layer (both facing down)?
A: Insulation layers are additive -- in other words, adding insulation rated at R-10 to the top of another one rated R-10 would result in a layer of insulation that had a rating of R-20 (if the two layers were not compressed or forced together excessively.) There is nothing wrong with using two thin layers instead of one thick one if that is more convenient. Using two vapor barriers is another matter -- there should be only one and that should be on the second layer, or make sure you slice through the vapor barrier in this second layer in numerous places before putting it up.