Separation of beam's layers is serious issue
Q. I am writing with a question about arched laminated beams that are a main structural element in my 27-year-old home. There are three beams in total, about 80 feet in length. A few feet from the end of one there is some delamination in the top 30 inches of a 15-by-4-inch beam, along with something like a fungus in some places. How should I repair this, or whom would you recommend to assess the needed repairs?
A. This sounds serious. There must be a roof leak in the affected area that has caused the delamination and the fungus growth. Laminated beams depend on the strength of each ply glued to the others. Individual plies are not able to withstand the weight the beam is engineered to carry. You should have a structural engineer investigate and suggest the best way to repair the damage after the roof leak has been addressed.
Q. I read your column dealing with a crawl space at a shore house. My daughter and son-in-law recently purchased an older year-round home at the Jersey shore. The house was raised several years ago to put the first floor above the flood plane. The result is a walk-in crawl space with flood vents on all four sides. There is no insulation between the joists under the first floor. After removing some first-floor carpet, it was discovered that the hardwood flooring is nailed directly to the joists with no subfloor. Obviously, insulation is needed. Please advise as to the R-factor. Should there be a vapor barrier facing the floor?
A. If by flood vents you mean that they are open at all times and provide adequate ventilation so the crawlspace is dry, except at flood times, it is probably OK to insulate between the floor joists. The height of the crawl space is also a plus. You can do so with R-19 fiberglass with an integral vapor retarder, which must be tight against the floor above. Since you will not be able to staple the flanges of the vapor retarder to the joists, you can use wire pieces with sharp points, called Tiger Teeth, to hold the insulation in place. However, if there is constant or even frequent moisture in the crawlspace, it is best to use rigid insulation. Use 2-inch-thick XPS (extruded polystyrene - blue, gray or pink). Cut it to fit tightly, and hold it in place with nails driven horizontally and partially into the joists, supporting the insulation every foot or so.
Q. We have a summer home on Cape Cod to which we added a screened porch on the back. Last year we converted the screens to windows with screens. We would now like to improve the floor, which is pressure-treated 2-by-6-inch boards laid close to each other. Could we put tile or something else durable over this with a new subfloor? What kind of subfloor would you recommend, since there is such high humidity there? Right now we just cover that floor with carpet.
A. You should cover the treated 2-by-6-inch floor with 5/8-inch plywood. Any floor finish can be installed on the plywood.
Q. We have experienced a recent frigid spell. All of the gutters on my house are loaded very heavily with large icicles, as are several houses in my neighborhood. I suspect that heat loss melting the roof snow is the cause. Am I correct? And if so, how do I fix it?
A. You are correct; heat loss from the heated space is causing snow to melt. It runs down the roof until it hits a cold area, such as an overhang or a gutter, where it freezes and creates an ice dam or fills the gutters and the downspouts, which causes the downspouts' seams to split.
The houses without icicles have no convective paths allowing warm, moist air to migrate to the attic. They also have well-insulated attics, and may have some attic ventilation. Attic ventilation is helpful in most cases unless a cathedral ceiling is insulated with closed-cell sprayed foam, in which case ventilation is not needed. The first thing to look for and correct are holes, cracks, etc., through which heated air can convect into the attic. Then the level of insulation may be increased and ventilation provided, if it proves desirable. These matters can be best addressed by hiring energy auditors or contractors trained in this type of detection. Your utility provider is a good place to start. If they don't provide such services, they may recommend firms that do.
Q. Our house is a vintage ranch with fairly tall IGU (insulated glazing unit) windows measuring 21-by-66 inches. A number of them had failed and started to fog up, so I had 15 of them replaced with argon gas IGUs. Aside from the blue hue, the replacement windows are functioning fine. The original window units were manufactured in Malta, Ohio. I found they were a very good window unit but had shut down their operations a few years ago due to a buyout. Do you have any comment on these windows? My concern now is that the contractor who replaced the windows had used the original gaskets. The gaskets do not appear to fit the glazing rabbet properly, and some are very loose and dry. Can you recommend a replacement gasketing? Would a silicone sealant suffice? The wood of the windows also appears rot free.
A. One family for whom I did consulting work several years ago had double-hung Malta windows throughout their house. The windows were so drafty that the slightest wind would cause their curtains to move. In strong winds, the curtains would literally fly. So I am not impressed with Malta windows, and it may be one of the reasons why they are no longer in production.
The new insulated glazing units should have been set in new glazing tape. The old ones should have been removed. Are you planning to have the IGUs taken down to replace the gaskets? If so, any glass company can sell you glazing tape or install it for you. But if you are not, I don't really know what to suggest, not having seen what the problem is. Caulking may be appropriate, but there may be a better way to take care of the problem.
Q. I have an oil spot in my driveway that I am not able to remove or cover with a coat of driveway sealer. You had mentioned some chemical that can remove it. Can you send me the name?
A: You will first have to remove the sealer so the oil spot can be treated. The product to use is TSP (trisodium phosphate). If it's not available in your state, substitute TSPPF (trisodium phosphate, phosphate-free). Sprinkle the crystals onto the spot. Sprinkle hot water onto the crystals and scrub with a stiff-bristle brush and let stand for 30 minutes. Scrub again as you rinse with clean water. You may need to repeat.
Q. The dormer over the bathroom in our 1830s farmhouse was just completed about six weeks ago. In addition, we replaced the windows on the second floor of the front of the house and had a new (metal) roof installed over the old shingle roof. We have always had an issue with ice dams in the 10 years we've lived there, but never to this extent.
Having read your column and purchased your book, I realize this is probably a combination of gaps in insulation in the attic and poor venting. The roofer installed a ridge vent; there are gable vents on the north and south ends of the house, and for some reason he put in a soffit vent the length of the overhang of the dormer. There are 6 inches of fiberglass insulation in the attic, and the contractor insulated with fiberglass between the studs in the new bathroom. I have to say, though, the enlarged bathroom feels colder than the old, smaller one did. My questions: After plugging whatever gaps I find in the existing insulation, will adding an additional 6 inches of fiberglass insulation the length of the attic make a difference in the icicle formation; and is it feasible to "wrap" the dormer with additional fiberglass from the outside (i.e. from inside the attic)?
A. The photos you sent illustrate a serious ice-damming problem, not only on the new dormer, but throughout the entire roof, front and back. Although you had the problem before the dormer was built, that is no excuse for the new dormer to be affected. Its roof should have been built free of this problem. Because of its shallower pitch, is the new bathroom ceiling following the pitch of the roof? In this case, is there enough headroom to apply 2-inch thick rigid insulation directly onto the existing ceiling finish, and cover it with new drywall? This should cure the problem of the bathroom roof. However, if the bathroom has a flat ceiling, although you can apply rigid insulation to it, is there access to its attic to add more insulation?
To reduce the ice damming on the main roof, you will first need to find any convective paths through which warm air from the conditioned space enters the attic, as these are the worst offenders. This may not be easy for you to find, particularly in an old house. You may need the help of someone trained in energy conservation, thermal imaging and blowdoor testing. Since you are in Vermont, I can recommend someone skilled in this technology with whom I have worked for years, if you decide to go that route. Once you have sealed these paths, adding insulation is the next step to consider. It is difficult to provide effective ridge venting to a standing seam roof, and few roofers do it for that reason. If the roofer installed an effective ridge vent on the new dormer, and if there is an unobstructed air space from the soffit to the ridge vent, this can be helpful. You can increase the insulation of the dormer walls from inside the attic by adding 1-inch-thick rigid insulation to the studs. This will not only add to the existing insulation but also reduce the heat loss through the studs. This will not, however, increase the insulation of the walls above the roof. If you can add rigid insulation to the interior walls of the bathroom and cover it with new drywall, this will be a much greater improvement.
Follow-up: I was asked recently how to remove pine sap from an outdoor grill and furniture, asking for suggestions from other readers. One reader has successfully removed pine sap with isopropyl alcohol, using a paper towel dampened with the alcohol. Another reader suggests that, if the pine sap is old and has hardened, it be heated with a hair dryer or left in the sun, and the bulk of the sap scraped with an old credit or gift card. Yet another reader has done so with turpentine.
• 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.
© 2009, United Feature Syndicate Inc.