In this photo, it is clear that the threshold of this exterior door is completely missing. It was also noted the most of the weatherstripping around the door frame was missing as well. The lack of proper weatherstripping will allow large amonuts of air infiltration into the home as well as allowing heat to escape from the home.
In the photo you can see how the home owner has cut and fit eps insulation in between the floor joists up against the rim joist. Then spray foam has been applied to seal the perimeter of the eps to the building framing to prevent air infiltration. A better use of foam would be xps due to its better vapor perm rating. Also insulating the entire wall with xps sheeting would greatly influence the energy effieciency of the basement exterior walls.
The article read to comment on was Enhancing Energy Efficiency in Historic Buildings. One thing learned from this article would be the interesting fact that homes built prior to 1940s had better energy efficiency than some buildings built 35 years after. This was due to common sense building factors such as window size and placement, which is only now really being paid attention to due to the increasing cost of energy. There is much we can do to improve new construction techniques and improve old historic buildings which is great for people in the energy auditing industry.
Air leakage has several paths throughout a home’s construction. Caulking that seals joints such as: wall to foundation, wall and roof, wall and floor where the floor penetrates the wall, and caulking around the windows. These are areas that should be looked at when looking for air leaks.
A home’s door has 4 major areas of air leakage. One: Beneath the door, check the seal. Two: Crucial corners (bottom of the door). Three: Upper Corners from not contacting the weatherstripping. Four: Along the Jambs from worn or improperly installed wheatherstripping.
On inspection the other day the crawl space ceiling had been sprayed with what appeared to be approximately 6" of closed cell foam insulation. Not only is the foam good insulation but it also clearly defined where the thermal & air barrier were, establishing the crawl space was not conditioned.
I read an article on home “Winterization” which almost verbatim mirrors the underlying reason for blower door testing, creature comfort and saving money/energy. The article spoke of sealing holes in the thermal envelope, insulation installation, sealing the HVAC duct system and checking that the fireplace is well sealed when not in use.
Air leaks and moisture problems go hand in hand. Drafty window glass condensates and rots down wood windows, drafty ceiling fixtures cause water damage on drywall and mold growth on attic insulation. Correcting one issue with air sealing a home prevents multiple other problems and pays for itself.
Blower door testing is now a requirement for energy audits. The patents are expired, the technology is basic and publicly available, but yet the cost of equipment still very high. We can expect that in the near future competing equipment cost will drop the price of this test so it becomes a standard for most home inspectors.
A blower door can be used to check the air integrity of the entire home. It also can be used to check the tightness of individual rooms within a enclosure. This is a deep diagnostics and not part of normal blower door testing
Multi point testing in both directions can be valuable as a diagnostic within a home outside of code compliance. By operating at different pressures in both directions the data can then be smoothed out providing accurate testing data for analysis.
A single pane window was examined using infrared thermography and identified to have some thermal leakage around the bottom and right side. This could potentially be a location for energy savings by addressing sealing issues and air gaps. The use of a blower to provide negative pressure in the building would help identify the issue by further magnifying the leakage.
Homes can save money and energy without the need for a professional energy audit. One big savings comes from heating and cooling which can be optimized by keeping proper maintenance schedules and installing a programmable thermostat. Replacing incandescent bulbs with LEDs and CFLs can greatly reduce energy consumption. Large holes in the home should be plugged, as well as attic access panels. Additionally, using electronics responsibly by managing the location of appliances and turning off certain devices while not in use are ways to save.
Air leakage is very common around recessed lighting. If the recessed lighting doesn’t have an air tight gasket kit installed it can lose a considerable amount of air. Another way to seal the light is with the use of a top hat and sealing the edges.
In the image titled Attic Knee Wall Vent it shows how a knee wall located in the attic can all own air leakage behind the batts of insulation. The edges of the insulation should be sealed to prevent air from getting behind the batts.
A blower door test can identify key problems with air leakage in a home. By using a blower door to depressurize a home, outside air is drawn in through leakage points and the air-leakage rate is calculated. This can help builders and homeowners identify the impact air leakage will have on energy rates and comfort.
There are some fairly easy steps homeowners can take to increase the energy efficiency of their home. Some of these include setting the thermostat at an appropriate temperature, changing filters regularly, and using ceiling fans. More intensive steps include upgrading the buildings insulation, appliances, and lighting to meet current energy efficient standards, which also provides a way for the homeowner to receive a return on their investment.