When building a new home, choose the best insulation for your house and location.
Blanket insulation is one of the most commonly used in the U.S. It is usually made from fiberglass, mineral wool, plastic fibers, or natural fibers. One reason this insulation is so popular is its price: it’s one of the most cost-effective options out there. It’s also relatively easy to install since it’s flexible and can be cut to size.
Another popular option is using foam boards, also known as rigid foam. These can be used to insulate a range of areas, including walls, roofs, and attic doors. Foam boards can be made from polystyrene, polyisocyanurate (a thermoset plastic), or polyurethane. They tend to have a high thermal resistance—up to two times what most other materials have for the same thickness.
Unlike traditional fiberglass blanket insulation that absorbs water, foam boards are water-resistant, making them ideal for basements. The downside? They’re often more expensive than traditional blanket insulation.
Rigid Fiber Board Insulation
Rigid fiber board, sometimes known as fibrous board insulation, is frequently used for insulating air ducts. It is usually made of fiberglass. Insulating your ducts is a good idea, especially when you consider that you can lose up to one-third of your heat through poorly insulated ductwork. The insulation of rigid fiber board is generally done by HVAC contractors, who fabricate the insulation before installation.
Concrete Block Insulation
If you’re building a new home, concrete block insulation is another option. This method involves insulating concrete blocks that are then used to build the home’s foundations and walls. There are a few different ways to do this. Blocks can be filled with insulation, though studies have indicated that core filling offers minimal fuel savings. Installing insulation over the surface of the blocks may be a better option. Precast masonry units like autoclave concrete are also available and can offer up to ten times the insulating value of conventional concrete.
Insulating Concrete Forms
Another option is to use insulating concrete forms (ICFs). ICFs are made of connected or interlocking foam boards or blocks that essentially form a cast for a concrete wall. These boards are often reinforced with rebar, before concrete is poured into them. After the concrete has set they remain part of the wall assembly. This type of insulation offers a high R-value, typically around R-20. However, they’re difficult to install and may not be available where you live.
Sprayed-Foam & Foamed-In-Place Insulation
Liquid foam insulation is a good option for filling in where you need extra insulation, including around joists, door frames, and window frames. It can also be used for bigger areas like attic surfaces or below floors, or even blown into walls. Small cans of foam-in-place insulation can be purchased for DIY cavity filling.
Blown-In Insulation (Loose-Fill)
Blown-in insulation, also known as loose-fill insulation, consists of small particles of cellulose, fiberglass, or other materials. Blowing the insulation into a wall requires specialized equipment but can be a good choice for insulating existing structures like closed walls. Fiberglass blown into an attic has an R-rating of 2.2 – 4.3 per square inch, while in a wall it has an R-rating of 3.7 – 4.3. This can be compared to traditional fiberglass batt, which has a rating of 3.1 – 3.4.
Radiant Barriers & Reflective Insulation Systems
Radiant barriers work by reflecting radiant heat. They are a good option for warmer regions or attics to help reduce heat transfer.
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