Disputing advice about below-grade insulation

Q. I wanted to comment on your article. I believe the energy auditors likely got it right on each of the three recommendations. Insulation most definitely should go more than 2 feet below grade. In fact, it should completely surround the building envelope, including under the slab. I believe your assumption that the drainage around the house was done improperly will mislead readers who don't read the article very, very carefully to the conclusion that insulation, and therefore heat loss, doesn't occur below grade. It most certainly does! The recommendation that the sill plate be sealed is a good one, in my opinion. The blower-door test likely showed that this was not done properly and there is serious air infiltration in this area. Fiberglass insulation will do next to nothing to slow air infiltration down. Fiberglass is what they make air filters out of! This is not a vapor barrier issue as you have suggested. This is a very significant source of heat loss, possibly equivalent to leaving a window open. This is an important issue, in my opinion, as there are a lot of natural resources being wasted needlessly, and the errors in your piece should be corrected so the misinformation doesn't continue to get spread. A lot of people look up to you for information of this type. It is important to have the building science correct, and it would be best if the corrections were to come from you.A. You are referring to my recommendation to insulate foundation walls to only 2 feet below grade unless the backfill was done with coarse material, there is a functioning foundation drain and the grade slopes away from the house. You have completely missed the point. Please read my answer more carefully and critically. The sources that you quote (deleted to save space) recommending that basement wall insulation be carried all the way to the floor do not mention anything about the local climate and soil conditions. They deal only with ideal situations. But I have the responsibility to advise my readers, conservatively, about how to do things that could otherwise turn out to have disastrous effects. I will assume that you haven't spent much time investigating cracked concrete and block foundations, as I have, or you would not be so quick to make such comments. I did not assume that the drainage around the house was done improperly; I cautioned that it could be, as I have seen so often. I am fully aware that heat loss occurs around the entire envelope of any building, but one must be careful not to cause serious problems by following the general recommendations of people who may not have fully treated the subject. When one is not sure that all necessary conditions for a safe foundation-insulating system are present, it is wisest to allow some heat to conduct through the foundation to keep the soil from freezing deeply, which could crack it. Soil is somewhat of an insulator as well, and if kept reasonably dry by proper grading, even more so. The auditors may be right in the case in point, but they can also be slack; I have run into that problem before. They, of course, had access to the building to do their testing, which I haven't. However, did they know the composition of the backfill and the condition of the drainage and take them into consideration? There are less expensive ways to control air infiltration at the rim joists than foaming them commercially, which is very expensive. Caulking will do a very good job, and the fiberglass insulation with a vapor retarder will provide the needed thermal protection and vapor control. The only correct statement you have made is that it is important to get the building science correct, and this is exactly what I have done. There were no errors in my answers - just cautious advice, which is what I continue to believe is my mission.I have removed wallpaper from a small bathroom, and there is a liner on the wall. It appears to be perfect - no glue or anything, just smooth paper. Before I put a new, heavy wallpaper up, do I need to prime and seal the paper? If I do not, will it be difficult to take the new paper off without taking the liner with it?A. There is no need to prime or seal the liner; it would actually make removal of the new paper harder and could damage the liner. Use only prepasted paper so it can be stripped later without damaging the liner. Wallpaper that is hung with paste will be very hard to remove and may actually take the liner with it.My ranch-style house was built in 1990. Every winter when it is cold outside my air conditioning vents drip water, and my exhaust fan drips water, too. The air conditioning was wrapped with insulation after the first dripping. I was told not to close the vents because the water would go around the vents, which did occur. I was told to run the air-purifying system, which is an added feature to my air conditioner to "dry out the vents." This helped but did not correct the problem. I was later told that I did not have enough ventilation, so we added a ridge vent. Do you have any suggestions?A. I assume that by "exhaust fan" you mean the bathroom fan, and that your air-conditioning unit and ducts are in your attic. I also gather that you live in a cold climate. Ventilation is not the problem. The condensation in the air-conditioning ducts occurs because warm, moist air from the living areas is convecting into the ducts through the ceiling vents and coming in contact with cold metal and a cold attic. No usual amount of insulation of the ducts will take care of this; the amount needed would have to be such as to turn the duct system into a conditioned space. And that would not take care of the coil system. For next winter, try to remove the ceiling grilles, fit a good chunk of fiberglass insulation in the ducts without crushing it, tape a plastic sheet over the opening and replace the grilles. This should stop the convection and isolate the duct system from the living spaces. As to the bathroom fan, my guess is that it is vented through the roof or high through a gable vent. If so, it should be rerouted to vent through a gable wall as low as possible so condensate does not run down the duct. The best way to do this is to use a schedule 20 solid plastic pipe of the type used for drainage. It comes in 10-foot lengths with a bell at one end, so you may need more than one length. If so, be sure to set the bell-end toward the fan and not the outside. Set small blocks of wood of decreasing size under each section of pipe (two per section is enough) in order for the condensate to flow toward the outside. Place 4-inch-thick fiberglass batts against each side of the pipe and another layer on top.I read your article regarding insulation of walls in homes built in the 1950s. We live in such a home, with an addition built in the '60s. How effective would blowing insulation in the walls be? How is it done? We have replaced the windows and have proper attic insulation.A. It depends on the type and amount of insulation in your walls. If you now have R-11 fiberglass or rockwool filling the stud spaces, it wouldn't make sense to do anything more. The best way to increase the wall's energy efficiency would be to add 1-inch-thick rigid insulation to the outside of the walls and install new siding. But that decision depends greatly on the type of siding you have and its condition. Many houses of that vintage have hardboard siding that, if not well maintained, is probably suffering from the weather and time. It may be time to replace it with new wood or vinyl siding after adding the rigid insulation. If you know for sure that your walls have only 2-inch-thick fiberglass - known as "masonry insulation," commonly used in the '50s - it may pay to have cellulose blown in. It would compress the fiberglass, but that is OK under the circumstances. It is generally done by drilling holes between the studs after removing some of the siding.My question is regarding cedar shakes. My contractor uses pre-dipped Maibec. However, the look I want is a Nantucket Gray. I know that they will need to weather, but I want to be certain that I have the right materials and the correct stain for Vermont. We also want them to be as maintenance-free as possible. Another contractor I know has recommended red cedar (Perfection) and said he would hand dip them. Somehow this seems like the preferable way if I want to achieve the results I am looking for.A. I assume that the pre-dipped Maibec are not of the shade you want, so having someone hand-dip the shakes in the stain of your choice sounds like the safest bet. A knowledgeable paint-store person can suggest the stain that would eventually give you the effect you want while it weathers in the Vermont climate.Great suggestionIn answer to my request for help, a kind St. Albans, Vt., reader provided the answer. A Lincoln, Vt., reader asked me whether I knew of a way to remove stubborn stains from a plastic laminate vanity top. She had tried everything I would have suggested to no avail. Here is the solution: "My husband purchased a lovely vanity that had been removed from a home being remodeled. It had several stains on the top and, like the Lincoln, Vt., reader, we tried everything. The stains did not come out. Our son took one look at it and advised us to use Turtle Wax Rubbing Compound. Presto, the stains all came out with no effort at all. My husband then simonized the top as you would a car. When he told a lady at our plumbing-supply house what he had done, she nodded her head and told him they do that all the time!"bull; Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. Write to him in care of the Daily Herald, P.O. Box 280, Arlington Heights, IL 60006, or via e-mail at henridemarne@gmavt.net.#169; 2009, United Feature Syndicate Inc.