Insulating walls is key to creating a thermally efficient home, and will depend on factors like climate and energy savings goals to determine the R-value needed.
Older homes typically feature two-by-four studs that do not reach four inches deep, making use of R-13 kraft-faced fiberglass insulation in rolls essential to heating efficiency and safety.
Foam boards and rigid foam panels are extremely effective at limiting heat transfer through materials used to build homes such as wood studs and wall panels, reducing its flow into your living space.
Fiberglass Batts
Fiberglass batts (commonly referred to as loose-fill insulation) are the go-to choice for residential wall insulation, offering various R-value options to meet the requirements of each home and can easily be installed between wall studs, joists, framing or drywall panels – providing homeowners with an economical way to reduce heating and cooling costs.
Fiberglass insulation can not only save on energy costs, but it is also effective at controlling temperatures and reducing noise pollution. Unfortunately, fiberglass can be itchy and irritating during installation, potentially leading to mold growth if exposed to moisture for too long.
If you choose fiberglass batt insulation, be sure to staple and seal all exposed framing, sealing any gaps with caulk as necessary. Furthermore, ensure the insulation fits between studs exactly — an improper cut batt can leave gaps or bunch up too large, drastically decreasing its R-value and creating unnecessary waste.
Blown-In Cellulose
Cellulose insulation made from recycled paper fibers is an eco-friendly choice that is often preferred by green builders. Treated with borate to repel pests and boasting a Class 1 fire rating compared to fiberglass batt insulation products, cellulose is considered superior.
Blown-in cellulose is applied to existing walls using a loose-fill method. Compressed bales are opened and fed into a blower whose nozzle is placed into openings in the wall, where rotating teeth or prongs in its hopper fluff up and scatter the material before being blown into position.
Cellulose insulation is denser than fiberglass and reduces the oxygen needed to ignite structural members, making it more fire-safe. Cellulose has become an attractive choice both in retrofits and new homes. When combined with polystyrene foam (EPS), expanded polyurethane or polyisocyanurate (PIR), R-Values in walls can be increased. Plus it’s less costly than other furnace-produced forms of insulation foams!
Spray Foam
Spray foam insulation is often utilized to increase wall insulation thickness. It is applied in thin layers that expand up to one inch thick for air seal and thermal resistance purposes, and generally considered one of the best choices for new construction or remodel homes, as it boasts an energy efficient R-value that easily meets and surpasses Department of Energy recommendations for your climate zone.
Closed-cell spray foam offers greater density than open-cell foam and creates interconnected pockets with high R-value insulation properties. However, applying it in existing walls may prove challenging due to having to remove portions of drywall in order to gain access to stud spaces.
Installing spray foam requires special equipment and training, so its installation should generally be left to professionals. Reach out to one of the top-rated professionals to gain more information about its advantages for your home’s R-value needs.
Mineral Wool
Mineral wool insulation, like fiberglass insulation, is composed of natural materials derived from rocks reclaimed from steel and iron ore industry waste rather than being sent directly to landfills. Furthermore, unlike fiberglass or cellulose products that lose their insulation when wetted down, mineral wool doesn’t compromise its insulating qualities when wetted.
Rockwool insulation can also be compressed into rigid boards for easier installation in walls and ceilings, and can even be cut or adjusted without diminishing thermal resistance.
Mineral wool insulation stands out as one of the better moisture-resisting insulation materials, with its moisture-proof qualities providing greater moisture control than other options. A wall with an infilled cavity featuring mineral wool insulation will have a lower U value than one with no insulation and even lower than those featuring 50mm cavities of brick or stone walls.
As with fiberglass insulation, mineral wool may cause itchy skin if exposed for extended periods, so when handling this form of insulation it’s wise to wear gloves, a mask, goggles and long-sleeved shirt as part of an appropriate protective protocol.