Sealing and Insulation A Do It Yourself Job In the Attic
There is probably no more cost-effective method for home comfort and energy efficiency than sealing and insulation, and do it yourself insulating costs a fraction of what a contractor will charge for it. The major area to be insulated in a modern home is usually the attic. Why the attic? It will become clear when the homeowner attempts to locate air leaks strangely enough, they aren' t where most people think they are, around windows and doors. Those apertures may let in drafts during the winter (which is when the family really feels the need for insulating the home), but most often the significant leaks are in the attic. Thats because warm air always rises up through the home; it is the suction of that action that creates drafts. Sealing and insulation should travel the opposite direction as the home is insulated, top to bottom.
That means that do it yourself insulating always starts with the attic, where the big leaks are found. Leakage there is most likely to be found where walls meet floor. In an already insulated attic, the homeowner should check for insulation with excessive dust and dirt in it; this means air is traveling through that particular section.
If the section with the leak is easily removable, the best method of insulating is to cut a piece, usually 16 inches long, from a batt of fiberglass insulation. Then this gets folded into a 13 gallon garbage bag, creating an insulation pillow that is stuffed into the space that is leaking, usually along one of the stud pieces holding the attic floorboards in place.
The bag should fit tightly (one can add more insulation if needed), and the floorboards can be quickly replaced. In the case of an entire area of insulation evincing a leak, one needs to remove the flooring of the dropped ceiling section (called a soffit) and cut reflective foil or foam board to cover the section. Caulk the board or foil around the edges, replace the insulation, and replace the floorboard.
In completing the sealing and insulation of the attic, insulation pillows like the one just created can also be stuffed into open join spaces under the attic wall (foam board or foil works well also), and, in hard to reach areas, the use of an aerosol spray insulation foam works wonders. One covers the area with fresh insulation.
One special area that needs attention in the attic is the furnace flue, a major source of heat loss as warm air moves through the attic. The flue pipe gets hot; therefore there must be at least an inch of clearance between pipe and insulation, to prevent fires.
There are several methods to insulating the home furnace flue.
One method is to cut aluminum plate (called flashing) into two pieces, each with a half circle, overlapping the middle by about 3 inches. One can set the two pieces around the pipe and then caulk, nail or staple the pieces together. The next step is to seal the gap between the metal-cut flashing and the furnace flue with high-temperature heat-resistant caulk (spray foam will not work, and is flammable, to boot).
One then creates an insulation dam by coiling aluminum flashing around the flue, folding the edges of the roll so that it creates a one-inch set of feet separating the coil of aluminum from the pipe. The dam is thus wrapped around the flue and secured at the bottom with staples; one can then replace the insulation, right up the dam, and not risk contacting the hot pipe.
Remaining gaps at edges, points between walls and attic floors, and pipe joins can all be sealed over with aluminum flashing and heat-resistant high-temp caulk (for use with galvanized metal and masonry pipes) or expanding caulk foam (for use with cast iron pipes).
Seal the attic hatch or door with insulating tape, and the attic has gotten the best sealing and insulation the do it yourselfer can offer!