Ice and water membrane deters buildup
Q. In the winter after it snows, icicles form down the shingles of my house on its back (east) side. We have a gutter that runs the entire width of the house, but there is no overhang off the roof. There is an overhang in the front of the house and icicles form off the gutter. What could be the problem, and how do I solve it?
Mundelein
A. It sounds as if ice dams are forming at the eaves of your roof. In the front where the overhang is, the gutter fills with ice, and it's likely that water backs up and gets into the soffit. In the back of your roof, where there is no overhang, water backs up behind the ice dam and gets under the shingles and into the wall (you do not have the protection of an overhang). This is a serious matter, as it may lead to wet sheathing, insulation, framing and eventually rot.
The simplest solution is to have a protective ice-and-water membrane installed under the shingles on both the front and back of your house. A contractor will have to remove slightly over 3 feet of the shingles, make sure the sheathing is clean and adhere a membrane such as Grace Ice & Water Shield onto it. If the existing shingles cannot be removed without damage (it depends on their age, brittleness and the skill of the person removing them), new shingles will be nailed through the membrane. This will not prevent ice dams and icicles from forming, but it will keep the water building behind them from getting into the soffit and the wall.
Q. I was interested in your comments about the toxicity of various materials mentioned in one of your recent columns. You responded to a reader who questioned your suggestion of a sheet of rigid insulation under their mattress. You compared the toxicity of foams and other plastics to that of natural substances such as wood, silk, cotton and wool. I am curious as to why these natural materials are more toxic. What's in them that makes them so lethal?
Via e-mail
A. I don't know what the chemical compositions of these substances are, but I can tell you why they are so lethal. Polystyrene foams are hydrocarbons (like wood). When they burn, they exude smoke that contains various chemicals and water vapor (burning wood incapacitates and kills faster than polymers, except for sulfur-containing polymers). When polyisocyanurate foams and natural fabrics burn, they emit hydrogen cyanide and are far more toxic than the polymers. However, the natural and polyester fabrics and fibers kill faster than the plastic foam.
To make it clear to those who may have missed the original question and answer, I was responding to a reader who slept on a cold porch and wondered if she should enclose the 2-foot space under the bed and fill it with insulation. My suggestion was to put a piece of 1-inch thick rigid foam insulation under the mattress. When I was actively involved in construction, working in building sites during winter, it was great sitting on a piece of foam scrap during lunch. Our rear ends felt so warm because our body heat wasn't lost through contact with poorly insulated materials.
Q. I'm hoping you can help! Recently, the oil filter on the oil furnace leaked and spilled about 30 gallons of fuel oil on the concrete floor of our log cabin. We cleaned the oil from the basement floor. However, there is a stain, and there are fumes in the entire cabin. What can we do to eliminate the odor throughout the cabin, including the furniture and carpeting?
Via e-mail
A. Try Knock Out, distributed by PTB Enterprises of Southfield, Mich, www.ptbent.com. The product is completely biodegradable and harmless to people, pets, fabrics, etc. You can order Knock Out on their Web site or by calling PTB Enterprises' toll-free number, (866) 478-2368.
Another product with which I have had very good luck is Nok-Out, manufactured by Amazing Concepts, LLC. It is only available from the distributor Neo Products at P.O. Box 190, Holly, MI 48442. Their toll-free number is (888) 977-4848. You can also order it online at www.nokout.com. In Canada, the distributor is OdorTech, located in Ontario. OdorTech's toll-free number is (877) 466-5688. Nok-Out works differently; it seems to have a chlorine base. Follow the directions in order to ensure success.
I have also heard from a Vermont reader who suffered a severe oil spill. She used NILodor with great success: NILodor, Inc., Bolivar, Ohio, (800) 443-4321, www.nilodor.com.
Q. My house is one level and fairly long (about 60 feet). Before 1996, it had only two small gable and soffit vents. That situation combined with some air leaks made for some big icicles in the winter. While replacing the roofing in 1996, we added a ridge vent. In 2000, we plugged up the air leaks and added insulation, which worked very well. Now, the ridge vent gets "plugged" up once we get enough snow on it. So for the last four to five years, I have been pretty good about going up and exposing the ridge. As long as I keep it open, I get little to no ice. Otherwise, I get 2 to 4 inches of ice at the bottom and small to moderate icicles. It seems that there could be a better way to vent the roof and minimize the melting of the snow. What are your thoughts?
Essex Junction, Vt.
A. What type of ridge vent did you have installed? Externally baffled ridge vents allow some air movement from the attic to take place through the snow, because snow is porous. This air movement from soffit vents to ridge vent, if unimpeded, usually opens up holes in the snow cover fairly soon, and as the air movement increases, the snow clears up. Non-externally baffled ridge vents can get so thoroughly plugged by snow that they become ineffective for long periods of time.
Some ice buildup and small icicles are unavoidable in our cold Vermont climate. This should not cause problems if you have a protective ice-and-water membrane installed at the eaves, valleys and around skylights and all other roof protrusions. It's a standard procedure for a quality job. You should not have to climb on your roof to clear snow from your ridge vent; not only is it risky, but it's not good for your roof either.
Q. Is there an American company like Wintite Energy Systems of Ontario making magnetic storm windows?
Barton, Vt.
A. Magnetic storm windows were originally developed by MIT and are now sold by Magnetite of Baton Rouge, La., (800) 624-8483, www.magnetite.com. They are very effective. You can call them to get the name of an installer that covers your territory, or you can order the framing material from Magnetite and buy the acrylic sheets from a local glass shop and make your own storm panels. Magnetite recommends the use of 100 percent virgin acrylic glazing; it's less expensive than Lexan and works very well.
Q. Our hillside cape is built on piers (creosote-coated telephone poles set on rebar/concrete footers). The skirt around the building extends from the sill to about 12 inches above ground level. Underneath, the joists have fiberglass bats held in place with window screening that keep the interior floor warmer.
How should the skirt be closed off to increase the warmth of the floor? It gets quite cool during winter cold snaps. Can we extend it into the ground and insulate inside with panels of Styrofoam? How should we vent it if it is enclosed? Currently, we have two hotboxes for incoming water and outgoing waste water. One has been retrofitted to protect the pipes to about 25 F before an electric light is turned on for additional warmth.
Westford, Vt.
A. I gather that the soil under your home is bare. If so, it should be covered with 6-mil plastic in order to keep soil dampness from permeating the floor's fiberglass insulation. Make absolutely sure that the ground under the home is higher than the ground outside, or water may pool on the plastic. If it is lower, you should build a barrier around the perimeter of the home approximately 1 foot in by placing concrete blocks every few feet and leaning 1-inch-by-12-inch pressure-treated wood boards against the blocks. Then pile dirt against the boards so that it slopes away from the house. The plastic should cover the boards and be stapled to them. Screw or nail furring strips to the top of the boards through the plastic, so the wind won't affect it. Plant grass on the new soil to prevent erosion from roof runoff.
Now you can safely extend the skirt all the way to the ground, using pressure-treated plywood to which you can adhere 1-inch-thick rigid extruded polystyrene (XPS) insulation. Make several panels easily removable, so you get ventilation during the warm weather. Cover these open spaces with screen panels in order to keep animals from nesting under your home. Ventilation is best provided with several panels on each of the long sides of the home. There should be one within 2 to 3 feet of each end of the building and at least one in the middle, depending on the length of the home.
Reader tips: A reader from New Jersey sent me this: "You recommend sealing the registers/vents of unused rooms with 'plastic or cardboard taped over the grille.' There is a product on the market called Magnetic Vent Covers made by Thermwell Products Co. As the name implies, they are magnetic and do not require tape. They are 8 by 15 inches and can be cut to fit the size of the registers/vents with regular scissors. I bought them in Home Depot."
Thank you for the reminder; sorry I didn't think of it at the time.
© 2008, United Feature Syndicate, Inc.