The Pros and Cons of Different Types of Insulation
There are many different kinds of insulation used in the building industry. Find out what’s good and bad about each type here.
When it comes to home insulation, changes in technology and how houses are built make things harder. Does the project just need a thermal envelope, or does your choice also need to be able to block sound or keep air out? The budget is always another thing to think about. Find out the pros and cons of each of the 5 best insulation options to help you decide.
Batt and Blanket insulation. Batts made of fiberglass, cotton, or mineral wool are good, basic forms of insulation. Pre-cut pieces fit standard construction techniques. Compression does not hurt performance as much as most people think, but it does make it harder to fit around pipes and wires.
• The optional facing helps keep the vapor barrier in place.
• Glass fibers can irritate the lungs, eyes, and skin, which can lead to problems with lung
• Bad installation techniques hurt the performance (rips, tears and open spaces)
• Heat can move through the building’s structure
Blown insulation, which is usually made of fiberglass or cellulose, is flexible and easy to install. Its small particles can fit into any space, fill existing walls with little damage, and fill to any depth you want. Settling can be helpful in attics, but it can be bad in walls. A good solution for putting things back together.
• It’s the cheapest option and easy to fill around pipes and ducts.
• Use it again by sucking it up with a vacuum and moving it.
• Like with batts, fiberglass dust can irritate the lungs, eyes, and skin.
• The weight of cellulose can be too much for some common types of ceiling construction.
• Retains moisture to the point of producing performance concerns and mold growth.
Spray foam insulation usually works better than any other kind because it stops air from moving, but the price can be a big problem. Open-cell foam, which has bubbles that pop, can fill any space but has a lower R-value and can let moisture through. Closed-cell foam keeps its bubbles together, making a full seal against air, water, and vapor.
• It has the highest R-value density and can be used on any surface, no matter where it is.
• Gets rid of the need for separate vapor barriers (closed-cell) and lowers the amount of sound that gets through.
• Installation makes toxic gas, makes a mess at the site, and leaks through joints and openings that aren’t sealed.
• Usually needs a subcontractor who has specialized training and experience.
• Costs a lot more than other materials.
Rigid foam is easy to install and works well. It comes in three main types: expanded or extruded polystyrene, and polyisocyanurate. Its density and R-value can get close to spray foam levels. All rigid foam is resistant to water, but only extruded foam sheets can handle being outside.
• It’s the only type of insulation that stops heat from moving through the structure.
• Installation doesn’t require any special tools or protection for workers.
• Prices are in the middle, between those of expensive spray foams and cheap blown and batt styles.
• Must be cut to fit around wires and pipes, then all cuts and joints must be sealed to keep the enclosure airtight.
• Rigid foam can’t be used for building parts, and many foams have to be covered with drywall in living areas.
Spray foam and batts stop the transfer of heat through air convection, and rigid foam can be set up to stop the transfer of heat through conduction. Reflective insulation works to stop the transfer of heat through radiant heat. Reflective insulation can stop heat from radiating from the undersides of roofs or other places where there is no airflow or direct contact. It works the same way as an insulated thermos jug.
• Used best in warm climates to reflect heat; good for wrapping pipes and duct work
• Simple to install; provides vapor barrier
• It doesn’t break down or get compressed like other cheap insulation materials do.
• Can’t be the only insulation in cold climates; sometimes added to rigid foam as a foil layer
• A build-up of dirt hurts performance.