Wood-Framed Walls
Wood-framed walls are the easiest part of the home to insulate since they can be treated in the same way as new construction. The main concerns for wood-framed walls are the thickness and accessibility of the wall cavity. Assessment of wood-framed walls should also determine the presence or absence of insulation.
A check for wall insulation is easily conducted by removing the electrical plug cover plates to check for insulation behind the plug or switch. Check all the wall insulation in this manner for several electrical points in the house to assure accuracy in your investigation.
WARNING! Before conducting this test, the circuit breaker should be turned off or the circuit fuse should be removed to ensure that the power is off!
Brick Walls
Brick walls in most homes are comprised of veneer and an interior frame with a small gap to allow air circulation. This prevents moisture from forming on the bricks, which can rot and ruin the frame. This air gap should not be insulated but the frame wall should be. Tests for determining insulation for standard frame wall depth and area can be applied to brick walls.
Stone or Other Solid Walls
Besides brick, your property may have walls made of stone or concrete. These can be treated the same as brick walls, although not all treatments are suitable for insulation and sealing. Extensive reframing on the interior may be necessary to form an insulation cavity and possibly even a vapor barrier. You may also choose to insulate the side-wall exterior or use other coverings.
Attics and Roof Areas
A lot of homeowners do extra renovation in the attic, thinking that hot air rises and therefore the attic would be the place where the heat loss is greatest. Some may just think that the attic is the easiest place to insulate. Others expect their heating bill to be drastically reduced (by as much as 50%) once some insulation work is done. But that’s not the whole truth. An attic does not lose as much heat as an uninsulated basement. An exterior wall may lose more heat than the attic. Padding the attic in an old house with more insulation is fine if the air leakage spots have been identified and padding will rectify the situation. It is of utmost importance to understand the necessity of sealing the attic.
Moisture poses another potential attic problem, originating from many sources: a leaky roof, frost, ice damming and outlets of leaky bathroom or kitchen ventilation fans.
Good attic ventilation is paramount to cool summers and dry winters. However, few older homes have sufficient vents. Air intake vents which provide good ventilation can be fitted at the soffit, roof, gable or peak spots which allow heat to be released. A typical good ventilation construction should be in the ratio of 1:300 where one unit of vent is required for every 300 units of floor area in the attic. Hence, an attic measuring 1,200 square feet requires a vent area of 4 square feet.
Adding an electric vent fan is one of the most