A home energy audit is a valuable energy-efficiency assessment tool used by your HVAC professional to identify devices, usage habits and systems in your home where energy conservation and home-efficiency upgrades could boost home comfort and reduce energy costs. Some of the primary equipment employed for an energy audit of your Sarasota or Manatee County home include a moisture meter to read moisture levels in building materials, an infrared camera to detect heat gain/loss in the home’s shell and a blower door test to pinpoint air leaks which affect moisture and heat gain/loss issues.
Air Leaks Inflate Your Energy Bill
Air leaks in a home’s shell or between the living spaces and unconditioned areas affect home comfort, indoor-air quality and energy bills. Air leaks may occur through gaps and cracks around windows and doors, access points of cables and pipes through the home’s shell, around recessed lighting, the attic hatch, leaky air ducts and even through walls via electrical outlets.
Air leaks cause your air conditioning and heating systems to work longer and harder to cool and heat your home. Since cooling and heating costs account for about half of the energy consumed in a home, finding and plugging those air leaks has the potential to sharply reduce overall energy consumption.
Blower Door Test Is Best
The primary methods used to detect air leaks in a home are a smoke device, such as a smoke pencil or an incense stick to detect more obvious air leaks, and a professional blower door test, which is the most comprehensive air-leak detection method available. While a smoke pencil may be used in a do-it-yourself air-leak test, it is best used in conjunction with a professional assessment along with the following components:
- A blower-door frame and flexible panel which is designed to fill an entire doorway.
- A powerful fan with a variable-speed motor is attached to the blower-door frame.
- One manometer (air-pressure gauge) is needed to measure air-pressure differences between the home’s interior and exterior, and a second manometer is used to calculate the fan’s airflow.
Blower Door Test Preparation
Your HVAC pro must properly prepare your home for the blower door test. This is a general checklist which you can expect during the day the test is performed.
- All windows and storm windows are closed.
- Close all doors, except for the door used for the blower-door frame.
- Open all interior doors.
- Important: turn off all fuel-combustion appliances (e.g. gas water heaters, stoves and dryers).
- For fireplaces and wood stoves, confirm all fires are out. Cover ashes with damp newspaper. Close dampers and close glass fireplace doors.
- Turn off all exhaust fans (e.g. kitchen and bathroom).
- Turn off electric clothes dryer.
- Your HVAC pro may seal combustion flues and dryer vents.
- Make sure mechanical ventilation inlet and outlet vents are closed.
Once your home is prepped and sealed, your HVAC pro turns on the variable-speed fan on low to begin depressurization. A walk-through of the home is done to check for anything unexpected, such as fireplace ashes being pulled across the hearth into the living spaces. The fan speed is increased until an air-pressure difference between the home’s interior air and exterior air reaches a pre-determined point (50 Pascals).
Air Sealing Your Florida Home
The results of the blower door test reveal the severity of any air leakage. If you’ve already made arrangements for your HVAC pro to simultaneously seal air leaks as they’re detected, then you’re in good hands. You may also choose to seal air leaks yourself, which doesn’t take much technical aptitude using caulk, foam spray and weather-stripping, but it could be time intensive and involve climbing and moving around in uncomfortable areas of the home, such as inside an extremely hot attic or accessing plumbing pipes.
While cracks, holes and gaps around windows and doors account for common air leaks, the following areas are also common and contribute potentially greater passages for air infiltration, and should be handled by your pro.
- Utility chases
- Kitchen soffits
- Recessed lighting
- Attic hatch or door
- Plumbing pipe penetrations
- Holes under bathtubs cut for plumbing traps
- Cracks at flooring and baseboards
- Basement rim joist
If you would like to improve home comfort and lower your energy bill with an energy audit, make sure the HVAC contractor you hire is adept at using a blower door test. For best results, contact Aqua Plumbing & Air, where quality service has been our hallmark to homeowners in Sarasota and Manatee counties since 1974.
Written by John Miller