Roof Venting Unnecessary
Thanks for an intelligent and informative article about unvented attics and the use of closed-cell spray foam ("Insulating Unvented Attics With Spray Foam," 3/07). After mentioning the common misconception that code-required venting significantly lowers the surface temperature of asphalt shingles, the article goes on to state that a properly constructed unvented roof assembly "is immune to the moisture problems that occur in vented assemblies and is much more likely to be energy-efficient."
The article also points out that several major shingle manufacturers now guarantee shingles installed over properly constructed unvented roofs.
Why, then, is there an item in the Products section (on page 125) for venting a shed roof where it meets a vertical wall? Not only does the "solution" directly ignore all the information in one of your main articles, but it also defies the laws of physics. Hot air will not rise, then conveniently travel downward through lots of smallish grids, then conveniently rise again. It will rise and remain at the highest point unless it can go directly up and out or be actively blown out by a different route.
It seems to me that a lot of wasted expense has gone into the building of vented roofs.
Wendy Jackson
Potter Valley, Calif.
Editor Don Jackson responds: We don't necessarily endorse every product we run. Keep in mind that there are still plenty of jurisdictions where the building official will require a venting product like the one you mention, whether it does any good or not. So we try to keep our readers aware of what's available.
Dangers of Thin Plywood Paneling
The article on skim-coating paneling ("A New Look for Old Paneling," 4/07) implies that the material is worth saving and is safe (not a fire hazard). In my experience, the type of paneling shown is extremely flammable and should not be kept or salvaged.
I recommend that you obtain some of this material and perform a simple flame-spread test. Compare it with any kind of drywall and any type of dry nominal lumber. Make sure the paneling is made of wood veneer, like that shown in the article.
I will never recommend that a client or friend keep or install this kind of panel product in his home.
Mike Allen
R&J Construction Services
Port Orchard, Wash
Gable Overhang: Strong Enough?
George Neuwirt's detail for a strong gable overhang (On the Job, 3/07) raises the question of how strong is strong enough. We hired a structural engineer to review the roof framing plan for a Maine ski cabin with a 36-inch overhang on a 4/12 roof slope, and he insisted that we start the "ladder" lookout rafters inside the exterior bearing wall — half within the cathedral ceiling and half cantilevered over the raked top plate.
Neuwirt's detail is easier to build, but as the overhang gets larger and the snow loads heavier, what is the limit of a tacked-on lookout ladder?
Also, as Neuwirt showed, the first rafter inside of the stud has to be full-sized to create a fire block. Anyone trying to save a 2x12 and scrap in a smaller 2-by drywall nailer along the wall studs would fail framing inspection.
Alan Ruesch, GC
Mercer Island, Wash.
Sticky Weep Holes
The discussion of weep holes (Q&A, 3/07) overlooks a potential problem: Honeybees. I've run into them only once, but they were behind brick veneer. I don't know how far they extended, but there were a lot of them. I would saturate the entrance with wasp spray, and five minutes later they would be coming and going again. The homeowner decided not to do anything further, but I could imagine a large section of wall gradually becoming saturated with honey, with unpleasant results.
Jim Newman
Luray, Va.
Take Care Before Cutting Foundation
Regarding the article "Installing a ScapeWel" (3/07): ScapeWels are good products and I have installed them in new construction. Installing one in an existing wall should be done only after careful examination of the structural issues, including the presence of rebar in the concrete, the connection of the floor above to the plate and band joist, and the potential inward force of the soil outside the wall.
In new construction, I've left a concrete beam at the top, with reinforcing steel wrapping the opening to help transfer the loads around the window.
Joe Bates
Noblesville, Ind.
More on Lithium-Ion Tools
I read "Lithium-Ion Cordless Kits" (4/07) with interest. In the specification chart, the box listing compatible tools is inaccurate with regard to Ridgid's lithium-ion tools. Ridgid actually has four compatible tools: an adhesive/caulk gun, a hand planer, an orbital jigsaw, and an impact driver. All of these tools, known as MaxSelect Dual Voltage tools, can run on a 24-volt lithium-ion battery or a nicad 18-volt battery.
Paul Fitzmaurice
Imre Communications
Baltimore
Fixing Discolored Plaster
Here's an additional tip regarding stained plaster (Q&A, 3/07): Even after textured plaster has been bleached, there can be a slight color variation. Rather than painting (and losing some of the texture), I dust the remaining discolored spot and the area around it with white talcum powder, using a powder puff. The talcum sticks to the texture without filling it. I used the trick in my own house after a sink overflow on the second floor, and eight years later I can't find the spot.
Mike Guertin
East Greenwich, R.I.
No Freebies
You nailed it with your article "End of the Free Estimate" (Business, 3/07). I never understood why contractors offered this service. I can remember scheduling three to seven estimates on a Saturday, wasting all day and a half-tank of gas, and maybe getting one or two jobs. Homeowners would say they just bought the house and were curious how much it would cost to remodel the kitchen. Or if it was an insurance job, they would often take my written proposal, submit it to the insurance company, then have "Uncle Bob" do the repair and pocket the difference.
I now give an hourly rate with a price range over the phone before I ever visit a site.
Mike Gooding
Knoxville, Md.
