This is the most common type of insulation. It comes in convenient rolls that are easy to transport and carry. Advantages: Widely available and familiar, standard widths and thicknesses are designed to fit between studs, joists, and rafters. Paper- and foil-faced versions have stapling flanges that make installation easy. Rolls of fiberglass must be cut by hand to fit spaces.
It compresses easily, which causes it to lose insulating properties. Environmental issues: Phenol formaldehyde, linked to cancer, is being phased out as a binder.
Labels warning of possible cancer risk from inhaled fibers are being phased out because regulators have concluded the fibers break down quickly in lungs. Advantages: More fire-resistant than fiberglass. Springs into shape against studs, so installation is staple-free and quick. Disadvantages: Not widely available; retains moisture — if allowed to get damp, it can harbor mold growth. Although the products may contain minute amounts of crystalline silica, a known carcinogen, studies have shown no evidence that inhaled rockwool fibers cause lung disease.
Comes in easy-to-handle rolls. Simple to cut for fitting around pipes. Contains a borate fire retardant, which also deters some insect pests.
This insulation consists of fluffy strands of fiber blown into attics and walls with a special machine. It fills nooks and crannies, eliminating cold spots. Disadvantages: The product is so fluffy that loose applications may lose up to half their effectiveness at very cold temperatures unless topped by blanket insulation or higher-density loose fill see cellulose below.
DIY or pro? Check to see if you can rent an insulation blower from your local home improvement center or tool rental store. But if the job is more complicated than that, definitely hire a pro to make the installation worthwhile in terms of energy savings.
Advantages: Effective at all temperatures, and can even perform better as the air gets colder. Environmental issues: Fibers are too big to lodge in lungs; dust is only a nuisance issue. Best use: Ceilings, enclosed existing wall or open new wall cavities, unfinished attic floors, other hard to reach places.
This is because as the installed thickness of loose-fill insulation increases, its settled density also increases due to compression of the insulation under its own weight. Thus, the R-value of loose-fill insulation does not change proportionately with thickness. Unlike most common insulation systems, which resist conductive and convective heat flow, radiant barriers and reflective insulation work by reflecting radiant heat. Radiant barriers are installed in homes -- usually in attics -- primarily to reduce summer heat gain, which helps lower cooling costs.
Reflective insulation incorporates reflective surfaces -- typically aluminum foils -- into insulation systems that can include a variety of backings, such as kraft paper, plastic film, polyethylene bubbles, or cardboard, as well as thermal insulation materials. Radiant heat travels in a straight line away from any surface and heats anything solid that absorbs its energy. When the sun heats a roof, it's primarily the sun's radiant energy that makes the roof hot.
A large portion of this heat travels by conduction through the roofing materials to the attic side of the roof. The hot roof material then radiates its gained heat energy onto the cooler attic surfaces, including the air ducts and the attic floor.
A radiant barrier reduces the radiant heat transfer from the underside of the roof to the other surfaces in the attic. To be effective, it must face a large air space. Radiant barriers are more effective in hot climates, especially when cooling air ducts are located in the attic. The reduced heat gain may even allow for a smaller air conditioning system. In cool climates, however, it's usually more cost-effective to install more thermal insulation.
Rigid fiber or fibrous board insulation consists of either fiberglass or mineral wool material and is primarily used for insulating air ducts in homes. It is also used when there's a need for insulation that can withstand high temperatures.
These products come in a range of thicknesses from 1 inch to 2. Installation in air ducts is usually done by HVAC contractors, who fabricate the insulation at their shops or at job sites. On exterior duct surfaces, they can install the insulation by impaling it on weld pins and securing with speed clips or washers. They can also use special weld pins with integral-cupped head washers.
Unfaced boards can then be finished with reinforced insulating cement, canvas, or weatherproof mastic. Faced boards can be installed in the same way, and the joints between boards sealed with pressure-sensitive tape or glass fabric and mastic. Liquid foam insulation materials can be sprayed, foamed-in-place, injected, or poured. Foam-in-place insulation can be blown into walls, on attic surfaces, or under floors to insulate and reduce air leakage.
Some installations can yield a higher R-value than traditional batt insulation for the same thickness, and can fill even the smallest cavities, creating an effective air barrier. You can use the small pressurized cans of foam-in-place insulation to reduce air leakage in holes and cracks, such as window and door frames, and electrical and plumbing penetrations. Icynene plastic insulation blown into the walls of a home near Denver.
Icynene fills cracks and crevices and adheres to the framing. Today, most foam materials use foaming agents that don't use chlorofluorocarbons CFCs or hydrochlorofluorocarbons HCFCs , which are harmful to the earth's ozone layer.
There are two types of foam-in-place insulation: closed-cell and open-cell. Both are typically made with polyurethane. With closed-cell foam, the high-density cells are closed and filled with a gas that helps the foam expand to fill the spaces around it. Open-cell foam cells are not as dense and are filled with air, which gives the insulation a spongy texture. The type of insulation you should choose depends on how you will use it and on your budget.
While closed-cell foam has a greater R-value and provides stronger resistance against moisture and air leakage, the material is also much denser and is more expensive. Open-cell foam is lighter and less expensive but should not be used below ground level where it could absorb water. Consult a professional insulation installer to decide what type of insulation is best for you. Other available foam insulation materials include:. Some less common types include Icynene foam and Tripolymer foam.
Icynene foam can be either sprayed or injected, which makes it the most versatile. It also has good resistance to both air and water intrusion. Tripolymer foam—a water-soluble foam—is injected into wall cavities. It has excellent resistance to fire and air intrusion. Liquid foam insulation -- combined with a foaming agent -- can be applied using small spray containers or in larger quantities as a pressure-sprayed foamed-in-place product.
Both types expand and harden as the mixture cures. They also conform to the shape of the cavity, filling and sealing it thoroughly. Slow-curing liquid foams are also available. These foams are designed to flow over obstructions before expanding and curing, and they are often used for empty wall cavities in existing buildings. There are also liquid foam materials that can be poured from a container. Installation of most types of liquid foam insulation requires special equipment and certification and should only be done by experienced installers.
Following installation, an approved thermal barrier equal in fire resistance to half-inch gypsum board must cover all foam materials. Also, some building codes don't recognize sprayed foam insulation as a vapor barrier, so installation might require an additional vapor retarder.
Foam insulation products and installation usually cost more than traditional batt insulation. However, foam insulation has higher R-values and forms an air barrier, which can eliminate some of the other costs and tasks associated with weatherizing a home, such as caulking, applying housewrap and vapor barrier, and taping joints. When building a new home, this type of insulation can also help reduce construction time and the number of specialized contractors, which saves money. Structural insulated panels SIPs are prefabricated insulated structural elements for use in building walls, ceilings, floors, and roofs.
When installed properly, SIPs also result in a more airtight dwelling, which makes a house energy efficient, quieter, and more comfortable. SIPs not only have high R-values but also high strength-to-weight ratios. A SIP typically consists of 4- to 8-inch-thick foam board insulation sandwiched between two sheets of oriented strand board OSB or other structural facing materials. Manufacturers can usually customize the exterior and interior sheathing materials to meet customer requirements.
The facing is glued to the foam core, and the panel is then either pressed or placed in a vacuum to bond the sheathing and core together. SIPs can be produced in various sizes or dimensions. Some manufacturers make panels as large as 8 by 24 feet, which require a crane to erect.
The quality of SIP manufacturing is very important to the long life and performance of the product. The panels must be glued, pressed, and cured properly to ensure that they don't delaminate. The panels also must have smooth surfaces and square edges to prevent gaps from occurring when they're connected at the job site.
Before purchasing SIPs, ask manufacturers about their quality control and testing procedures and read and compare warranties carefully.
SIPs are available with different insulating materials, usually polystyrene or polyisocyanurate foam. SIPs are made in a factory and shipped to job sites. Some insulation, such as cellulose or cotton, holds moisture more than others, such as cementitious foam. Foam insulations tend to hold their R-value very well for the first two years because the gases in the foam block airflow.
Then the gases begin to escape, and the R-value drops. A foil radiant barrier can help overcome this. Homeowners in cold climates might want to chose cellulose; its efficacy actually increases at lower temperatures. The higher the R-value, the better the insulation. The overall R-value is the insulation rating per inch of thickness multiplied by the number of inches installed. R-value rating may vary by brand. How much insulation you need depends on your climate.
Check the U. BioBased soy-based polyurethane foam spray. Green Zone resources for CFC-free polyiso. Johns Manville formaldehyde-free fiberglass.
Icynene foam insulation is blown in using water and contains no CFCs or formaldehyde once cured. Formaldehyde-free Johns Manville MR-Faced Batts fiberglass are treated with a food-grade preservative to protect against mold growth. Johns Manville Spider is a formaldehyde-free, spray-in fiberglass insulation that contains some recycled-glass content. For use in open walls only. Published on Nov 1,
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