• Insulating heating and air conditioning ducts saves energy.air conditioner, conditioning image by Greg Pickens from Fotolia.com
  
  Feeling a cold blast of air when turning on the heater or attempting to cool a home and sending a stream of heated air through the rooms is a sign that the ducts need insulated. "Properly insulating the ducts located in unconditioned spaces such as attics, crawl spaces, garages, or unfinished basements can help improve your home's energy efficiency," according to the U.S. Department of Energy.
  
  

Flexible Formed Insulation

• Flexible formed insulation is constructed of materials such as wool, minerals, plastic, natural and fiberglass fibers. This insulation is designed for installation on round duct work. It is a must to use in areas such as cramped crawl spaces and attics that leave precious little room between the ducts and the floor or ceiling joists. Accurate measurements are needed to ensure the purchase of the correct R-value, or insulation thickness for your needs. Compromising a little on R-value protection is necessary when the space is severely limited. The length of the material is precut to fit snugly over the ducts. Coming in six to ten foot lengths, measure and cut the edges with a sharp utility knife to provide a straight edge for a perfect fit. The precut openings and separate pieces will all need to be securely closed using insulation tape. This product is moderate in both price and installation difficulty.
  
  

Fiber Wrap Insulation

• Fiber wrap insulation is constructed of many of the same fibers as the preformed product, but it is not as densely packed. Sold in rolls, it is the least costly of all duct insulation. Wrap insulation is the most effective in areas of varying duct sizes and shapes. The flexibility of the product surface allows for a custom fit, no matter how oddly shaped the various duct work appears. Working with this type of insulation takes a bit of practice. When the workspace is limiting, cut off lengths from the roll that will fit through the available space as you wrap the duct. Installation of this product is moderate to difficult, but the low cost makes this product an attractive option.
  
  

Fiber Board Insulation

• Fiber board duct insulation is made up of resin-based fiberglass or mineral wool. The surface is coated with a material that is high temperature resistant. This product is only used in rectangular or square shaped duct systems. Installing this type of insulation is extremely difficult and normally requires an HVAC (heating and air conditioning) specialist. This makes it the most costly of all options, but the custom fit, durability and insulating quality is hard to beat. When installed inside the ducts it has to be measured and cut for an exact fit in each section of duct. This means the duct system has to be completely disassembled and put back together one piece at a time. All gaps between the boards are sealed with pressure sensitive tape that is rated to withstand high temperatures. Installing this type of insulation outside of the ducts requires special fasteners that will hold the boards securely. All areas of the boards that are cut have to be treated with insulating cement.