The attic is one of the most important areas in the house and therefore it should be adequately insulated to minimize heat loss. The insulation needed in the attic will of course depend on the geographic location of the structure. In both crawl and unfinished full attics, the insulation should be located in the floor (between the floor joists) and not between the roof rafters. Otherwise, heat from the rooms below will escape into the attic.
Some of the important attic insulation tips are insulation should be installed with a vapor barrier facing the heated portion of the structure and not the unfinished attic area. A vapor barrier is an aluminum foil, a plastic sheet or an asphalt-impregnated paper that prevents moisture movement from the heated portion of the house into the unfinished attic area. If the vapor barrier is incorrectly positioned (facing up into the unheated, unfinished attic), condensation problems can develop during cool weather. Moisture rising from the heated areas below condenses upon contacting the cool vapor barrier. Depending on the amount of vapor, the resulting condensation buildup can reduce the effectiveness of the insulation and cause peeling and flaking of the painted ceilings and walls in the rooms below.
If there are heating or air-conditioning ducts in the attic, check to see whether they are insulated. Metal ducts often have insulation in the inside, so tap the duct with your flashlight. If you hear a hollow sound, there is no insulation. If there is a dull thud, insulation is present. The more insulation on a duct, the less the heat loss during the winter and, in air-conditioning ducts, the less the heat gain during summer. Generally, a minimum of 3 inches of insulation wrapped around the outside of the duct will substitute for missing insulation. If the duct is used for air-conditioning, the insulation should be covered with a vapor barrier to prevent condensation from forming.
Additional attic insulation tips are especially for houses in the northern section of the country, when there is a furnace in the attic, insulation between the roof rafters as well as in the attic floor is recommended. To ensure proper ventilation and avoid condensation problems between the rafters, it is important to leave a ventilated air space between the top of the insulation and the underside of the roof deck. The insulation and the associated air space will help keep the roof deck cool. If the insulation is not between the rafters, heat from the furnace will warm the roof deck and melt the bottom layer of snow that has accumulated on the roof. This often results in an ice dam.
Others attic insulation tips that you might want to consider are adding more or additional attic insulation to bring the total insulation up to current energy standards. The attic insulation added should not have a vapor barrier if the existing insulation has one. All too often the homeowners adds insulation with a vapor barrier, which can then cause condensation problems. Look at the insulation in the floor. If there are two layers of insulation and both have vapor barriers, the upper barrier should be slit with a razor blade to allow moisture movement.
Moreover, if there is a full attic with partition walls forming rooms, the attic insulation should be located on the unfinished sides of the partition walls and on the ceilings of the rooms. Occasionally, attic insulation is placed between the roof rafters ad not between the floor joists and the partition walls. This installation is inefficient because the heat will escape into unfinished areas.
In conclusion, here are some quick recap of attic insulation tips. Remember vapor barrier should face the heated portion of the structure and not the unfinished attic area. If there are heating or air-conditioning ducts in the attic, check to see whether these ducts are insulated. Check if additional or more attic insulation is needed. Basically here are several questions that you should be asking yourself when you are purchasing a house or consider attic insulation, is the attic insulated, is additional insulation needed, does existing insulation contain a vapor barrier and is insulation properly installed.
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