Insulation and Sealing

  • Attic Insulation

    A common reason for energy loss in the home is insufficient insulation. Insulation in the attic or ceiling is one of the most important aspects in providing a boundary between your home and outside air. It also helps to minimize the heat lost during winter and reduce the amount of heat gain in winter.

    To see if you have enough insulation, measure the amount currently present. If the amount is less than 6 inches thick, you might consider adding insulation to your home.

    Next, determine the type of insulation – the three main types are fiberglass, cellulose, and foam. Fiberglass is the most common, cheapest, and least efficient. It looks like cotton candy with the main colors being white, pink, and yellow. Cellulose is a little more expensive, and the most common used for do-it-yourself installation. It is made of recycled paper mixed with harmless chemicals making it bug-proof and fire retardant; it also reduces outside noise. The final insulation type is foam, the most expensive and efficient insulation available. Foam must be installed by a professional and the average payback is five years.

    The efficiency of insulation is stated in R-values. R-value is the resistance to heat a product has – the higher the R-value, the more heat resistant. Most product labels state the R-value per inch, which is the baseline for each product’s efficiency. According to the Department of Energy, the R-values for the three most common types of insulation are: fiberglass-2.5, cellulose-3.5, and foam-6. CAEC recommends having your attic insulation at R-38. Below is a graph showing how many inches of each type of insulation is needed to reach R-38.



  • Insulating Water Lines

    Insulating your home’s water pipes reduces heat loss and can raise water temperature 2-4 degrees Fahrenheit hotter than uninsulated pipes, allowing for a lower water temperature setting. You also won’t have to wait as long for hot water, which helps conserve water.

    For exposed lines, such as in the crawlspace, or under a manufactured home, use pipe insulation foam to insulate the lines. Be sure to use the correct diameter based on the diameter of the pipes (i.e. if the diameter of the pipe is three-quarters inch, use the same size insulation). This will insure a tight seal around the lines. When installing foam insulation, do not leave any gaps where cold air could freeze the pipes.

    For a home built on a slab foundation, you do not have to insulate the lines since they are covered by the concrete slab itself. But you do need to keep outdoor faucets protected for cold weather. An easy way to prevent the exposed faucets from freezing is fitting them with faucet covers, available at your local hardware store.

  • Insulating Foam Sealant

    Air leakage through small holes and cracks around the home is a major cause of heating and cooling loss. According to a report by the Oak Ridge National Laboratory and Pacific Northwest National Laboratory, a homeowner can save 10 to 20 percent on their heating and cooling costs just by closing up those air leaks. To reduce energy costs, air-seal and eliminate drafts by applying insulating foam sealant throughout your home. Foam sealants expand to form an outer skin containing closed air cells providing an effective barrier against energy loss and can be used around windows and doors, plumbing fixtures, electrical outlets, baseboards, sill plates, exhaust vents, siding edges, sky lights, attic fans, garage ceilings, etc.

    Insulating foam sealants come in different applications (i.e. windows and doors, gaps and cracks, firelock, aquascape, and landscape). Be sure to apply the appropriate foam sealant and read all directions thoroughly before applying.


  • Blower Door Testing: Is My House Leaky or Tight?

    When you hear of leaks in your home, you probably think of those involving water and plumbing, but what about air leaks? Homes that experience excessive air leakage are difficult to heat and cool. Too much air flowing in and out of your house can cause several problems such as wasted energy and high cooling and heating costs, moisture condensation, uncomfortable drafts from the outdoors and poor air quality flowing throughout your home. In fact, air leakage can account for up to 30 percent of your cooling and heating costs. The only way to know whether your home is leaky or tight is to measure its air leakage rate with a blower door test conducted by a trained professional. This test provides a highly accurate and cost-effective method for determining your home’s air leakage performance.

    A blower door is a powerful fan that mounts into the frame of an exterior door. The “door” comes with a built-in fan and multiple gauges that measure air pressure. The fan removes air from your house, lowering the pressure inside. In turn, higher-pressure outdoor air will work its way through cracks and unsealed openings, making the leaks easier to measure and locate.

    Before a blower door test can be performed, the following preparation is required:


    • Close all exterior doors and windows
    • Open all interior doors
    • Remove any ashes from open fireplaces or cover the ashes with damp newspapers
    • Walk-through your home with the auditor to point out areas that you know are drafty or difficult to condition comfortably
    • Close any fireplace dampers, doors and woodstove air inlets
    • Turn off the clothes dryer and all bathroom and kitchen exhaust fans

    Once the blower door is set up and operating, many leaks can be found by feeling around with your bare hands or with the use of an infrared camera. The infrared camera finds air leaks through temperature differences. To use the camera alone, the temperature outside and temperature inside have to be very different, but since it’s difficult to plan an audit around the temperature outside, it is best to use the blower door and camera together. By creating a pressure difference that allows the air to move, it is not necessary for there to be a large temperature difference to be able to see the air movement through the cracks and holes allowing for a much better chance to find all the problem areas. View our video about this process.

    After the blower door test is completed and the air leakage rate for your home is determined and evaluated, the auditor will assist you in identifying improvements that will potentially save the most on your energy costs and recommendations to improve comfort and indoor air quality can then be made.

    When you have a home energy audit conducted by CAEC’s Energy Services Representative, a Certified Residential Energy Auditor, you can choose which level works best for you and your budget. The initial cost of either audit is reimbursed when ESR-recommended improvements are made to the home within a 12-month period of time. The Basic Audit cost is $75 and the Advanced Audit (includes blower door test) cost is $100. For more information, see our energy audit page for more details or call (800) 545-5735 ext. 2178 or (334) 351-2178.


  • Insulating and Sealing Your Attic Access

    Even in a well-insulated home, one of the most com­mon and overlooked areas for an inadequately in­sulated space may be the access to the attic. Your home’s attic access, which could be an attic hatch, pull-down stairs or a knee-wall door, is often uninsulated. A one-quarter inch gap around the perimeter of an entry can potentially leak the same amount of air supplied by a typical bedroom cooling and heating vent.

    But before insu­lating the area, you should first deter­mine the recom­mended insulation R-value. An R-value indicates insulation’s resistance to heat flow – the higher the R-value, the greater the insulat­ing effectiveness.

    The location of your attic entrance will affect how or whether it should be insulated. For example, if the access is in a garage where the attic is uninsulated, you can eliminate the need for insulation, but if the entrance is in your home, such as in a hallway, you may need to invest in insulation.

    Attic hatches, or scuttle holes, are the most common forms of access and easily fixed for energy efficiency. The hole is simply a removable portion of the ceiling allow­ing entry to the attic and is most likely located in a closet or main hallway. Usually, they are constructed from thin wood or drywall, neither of which provides any substan­tial resistance to heat loss. For sealing, weatherstripping can be installed either on the hatch itself or on the inside of the trim or base where the hatch rests. For insulation, attach a piece of fiberglass batting (the easiest material to use for this type of opening) on top of the hatch. Add a latch bolt to help ensure a tighter seal.

    When gaining attic access through pull-down stairs, the frame encasing the stairs fits in an uneven opening and leaves a gap, much like a door or window, which must be sealed. If the gap is small (less than half an inch), caulk can be used as a sealant. If a larger opening exists, then a non-expanding foam or a backing material is suggested in combination with the caulk. Although expanding foam can be applied, be cautious because of its highly expansive nature, it could potentially distort the frame and obstruct the ability of the stairs to open and close correctly.

    Furthermore, to insulate attic stairs, a moveable box can be constructed from rigid foam or fibrous duct board to fit over the stairs from the attic side. For added insulation, attach a piece of fiberglass batting on top of the box. Insulating kits are also available through weath­erization suppliers or from local hardware stores.

    A knee-wall door is typically a partial size door that is usually found in the upstairs level of finished-attic homes. These doors are often poorly insulated and un­sealed around the frame. Make sure the knee-wall door is weatherstripped around the frame and insulate the attic side of the door. Add a latch that pulls it tightly against the frame to achieve a solid seal.

    A well-insulated and sealed attic access will prevent air leakage in your home, thereby reducing energy costs and preventing discomfort. Most attic insulation and seal­ing systems require minimal time to install using simple tools and techniques. And as with all home projects, be sure to follow the manufac­turer’s instructions for proper installation and safety.

  • Air Sealing Your Home

    When you turn on your air conditioner or heat unit, you often make sure all windows or doors are also closed so your en­ergy dollars don’t go flying out the door. This same principle is also true when it comes to cracks and holes throughout the house. These air leaks cause your cooling/heating unit to run longer and harder and in some cases, there may be enough cracks around the house that if you added them all together, it would be about the size of an open window.

    Air sealing your home, both inside and out, is one of the most cost-effective ways to improve energy ef­ficiency and comfort. Ac­cording to a report by the Oak Ridge National Labo­ratory and Pacific North­west National Laboratory, homeowners can save 10-20 percent on their heating and cooling costs just by closing up those air leaks. Buy a tube of caulk and a can of sprayfoam and seal anywhere you see a crack or hole. When you seal your home, it stops air from moving freely between the out­side and inside of your house. So how do you determine where to seal around your home?

    A good strategy is to simply walk around the outside of your home and caulk or foam any openings you see, especially around pipes or wire penetrations. Additional air leaks and drafts are easier to find because you can feel for them – such as those around windows and doors.

    Inside your home, the main area for air leaks is where your wall meets the floor or ceiling. Typically there is molding in place and you can caulk around the molding. Other com­mon places include air penetration points in the ceiling, such as near ceiling fans and lights and the attic access. Sealing these leaks with caulk, spray foam or weather stripping can have an impact on improving your comfort and aide in reducing your utility bills.

    Leaks also allow moisture to come into your home. Your cooling unit regulates both tem­perature and humidity, but when moisture is added to your home, it can become very humid and uncomfortable, especially during the hot Alabama summers, causing your unit to run even more.

    A tube of caulk and a can of spray foam are fairly inexpensive, and sealing your house is an easy way to lower your energy bills while gaining comfort.