The first question that you should ask yourself is whether your house is actually insulated. Old homes, circa 1920s and up have double walling or cavity walls and large percentage of them (excluding homes that are less than 10 years old) have inadequate or no insulation at all. Here are some telltale signs that your home is poorly insulated:
- Ice dams and icicles on your roof (also indicates poor ventilation)
- “Hot spots” in the summer and “cold spots” during the winter inside the house
- Drafty walls
- High utility bills
- Mold in the corners of your ceiling
- Stains on ceilings and walls
- Drafts coming through wall plugs
If you have any one of these signs, then there is great chance that your home has inadequate or poor insulation. Re-insulating your home is the best way to make it more energy-efficient and cost-effective.
Stains on the attic ceiling can go two ways: the water stains are from actual leaks on the roof or the stains are from condensations. To differentiate, stains from actual leaks are larger and will appear at the sides of rafters and on the roof sheathing itself. If the moisture is from faulty insulation the condensation will appear as drips on the rafters.
Insulating the rafters and studs has been overlooked in most instances. When the roof and walls are not insulated, the rafters and studs have the highest R-value at 1.25 per inch. Once the walls and ceilings between studs and rafters are insulated, the framing becomes the “weakest” link in the insulation due to thermal bridging. Simply put, insulated walls and ceilings could have an average R-36 whereas the studs and rafters remain at R-1.25. The solution is simple. For new homes, blown-in insulation for the attic and spray in or batt insulation for the walls. For older homes, remove a wall plate from a plug on an exterior wall. If you feel a draft on a windy or cold day, you are lacking insulation.
Be sure to check out the fascia and soffits too as there could be leaks and molds there. Check for protruding nail heads on surfaces. If they have rust and water stains around them or frost (in the winter) then the probability of condensation is high. Look for the source of condensation in the attic and fix it.
Aside from drafty rooms, air leaks cause health-hazardous molds to form. Molds are sure to form too if there is high condensation. It is easy straightforward to see molds on attic ceilings and basement flooring. However, molds on the inside of a cavity wall may not be evident until the mold progresses to the exterior face of the cavity wall.
If your home was built before 1980, there is an 80% probability that it is not sufficiently insulated. Homes built before 2003 also need to be inspected.
Blown-in insulation is the best option to use for insulating existing cavity walls and unfinished attics. Make your home “green” and energy-efficient.