OWNER BUILT | TP OF THE MONTH

February

INSULATION

         If you are buying or building a new home, make sure that the recommended energy-saving insulation values are used. Most new home builders have an R-13 exterior wall value with an R-30 ceiling. This is typical with 2 X 4 exterior wall construction as more insulation will not fit in the wall cavity. With 2 X 6 construction R-19 is achieved and more energy savings can be made. Upgrading to R-38 in the attic is recommended since most of the heat and cool transfers thru the ceiling. Rarely will someone go beyond R-38 due to the expense vs savings over short term investments.

            There are 2 types of commonly used insulation. Batt or blanket and blown insulation. Batt insulation is usually used in the walls and in the attic areas that do not have crawl space access, like a flat roof, between floors as a noise dampener and can be used to create “sound walls” by bathrooms and entertainment areas that are near bedrooms. Batt insulation can have gaps by the studs, around outlets, and at the top or bottom if it is not installed properly. The blown insulation can be used in exterior walls and attics that have access. It is installed by mixing water with a combination of fibers and cellulose and blowing it thru a hose. It seals air gaps around outlets and does not have any voids if installed properly and can achieve an R-24 in the exterior walls. It has to dry for a minimum of 3 days before covering it up with sheetrock. The attic is blown after the sheetrock has been installed on the ceiling and is a dryer mixture. R-38 is 12” thick. A common problem however is when the insulation covers the can lighting in the attic space which will trigger the thermo switch to activate turning the light off after a few minutes of operation. Once it has cooled down the light will turn back on. This situation can be remedied by clearing the insulation away from the can light allowing passive ventilation.

          Keep in mind that every surface has an R-value. The windows, doors, sheetrock, plywood, lath, stucco and roofing all add up to savings with the utility bills. Some subdivisions have requirements given by the Dept. of Energy that have to be met. These are minimum requirements and should be upgraded by a new home buyer whenever available. Special care should be taken when sealing penetrations not covered by insulation like the gap between the bottom of the wall and the foundation. It is recommended to use high quality elastic calking around the entire perimeter of the home. This is usually done on the inside because of accessibility reasons. The framing contractor will usually put a foam strip between the foundation and sill plate but due to the uneven caricature of concrete there are usually gaps. The same thing happens around the exterior door frames and window frames and should be sealed to prevent air loss. Some cities are now requiring insulation inspections before hanging any sheetrock and special care should be given by the new homeowner that it is properly installed so their utility bills can be kept at a minimum under the various circumstances. Ownerbuilt clients are given a checklist to assure all procedures have been taken prior to proceeding to the next step.

* The information contained in this “tips” section is to be used as a general guide only. When making decisions about your project a professional should be consulted using the specific information that is unique to your project.