Blanket insulation is the most extensively employed type of building insulation. Blankets are basically composed of flexible materials prepared from mineral fibers such as fiberglass, rock wool etc. Other materials which can be used in the formation of blanket insulation include:
- Slag wool
- Plastic fibers
- Natural fibers, For example, Cotton wool, Sheep wool
These blankets are usually available in the shape of batts and rolls. The length of a typical batt is either four or eight feet. Batt and Blanket insulation can be installed in variety of places ranging from area beneath the floors to top of the ceilings for providing thermal insulation. Besides, it can be employed inside the walls of the building. As compared to other building insulations available in the market, batt and blanket insulation is considered to be extremely economical. Batts and blankets are generally available in widths which can firmly adjust between structures having wooden frames. Regular blanket insulations having low density offer low R- values in the range of R-2.9 to R-3.8 per inch of thickness whereas high and medium density batts and blankets offer high thermal performance in the range of R-3.7 to R-4.3 per inch of thickness.
Batt and blanket insulation is mostly preferred for wall studs, rafters and floor joists having customary spacings. Long and continuous rolls are normally cut by hand and trimmed in order to make them compatible for installations involving non standard spacings, for instance, places close to windows, doors and corners or areas encountering barriers inside the wall like electrical wires, outlet boxes and pipes etc. Sometimes, blanket insulations are provided with radiant barriers. Batt and blanket insulation comes with variety of facings as well. A facing can be of great help for the installation procedure since it makes fastening easy. However, faced batts are of no use in case the reinsulation is going to be done. The most common types of facings available are:
- Vapor-retarder facing: In this facing, materials such as kraft paper, foil-kraft paper and vinyl are employed to behave as a vapor and air barrier.
- Flame- resistant facing: This type of facing is mainly provided in areas where insulation is open to hazardous surroundings, for example, in basement walls. Exclusive flame-resistant materials are used for this purpose.
Installation of batt and blanket insulation must be done with proper care and precautions so that the thermal resistance and efficiency of the insulation doesn’t get affected. This type of insulation can be put either by uncertified personnel or skilled professionals. However, it is strongly recommended that a certified insulation installer must be hired to perform the installation. The professional way of installing blanket insulation includes following steps:
- Get approximate cost calculations from a number of insulation installation contractors for a particular thermal performance or R- value required by you.
- Make enquiries regarding air-sealing services provided by those contractors and get their price quotes too.
Analysis of Batt and blanket installation can be done by examining thickness of batt and testing out gaps among batts.