Closed-cell spray foam insulation offers the highest R-value per inch, providing approximately R-6.5 to R-7 per inch. It acts as a premium thermal barrier and air-sealing system. Rigid foam boards (like Polyisocyanurate) come in second, providing about R-6 to R-6.5 per inch.
The highest R-value insulation you can buy for residential applications is Vacuum Insulated Panels (VIPs), which offer an incredible R-30 to R-45 per inch of thickness.
In colder regions, R49 insulation is essential for roofs and attics to retain heat and lower heating costs during winter. In milder climates, R38 insulation offers sufficient thermal resistance without unnecessary material expenses.
R60 insulation is worth it if you live in a very cold climate (like the northern U.S. or Canada), but it is often considered overkill for mild climates. While it maximizes comfort and thermal efficiency, you will experience diminishing financial returns compared to standard R38 or R49 insulation.
R-11 insulation is a 3.5-inch thick fiberglass batt designed for 2×4 wood or metal framing. It is primarily used for interior wall soundproofing and milder climate exterior walls to provide basic thermal resistance and noise control.
R-13 is generally better for exterior walls. It provides about 18% more thermal resistance, is denser, and meets modern building codes for most climates. R-11 is usually only recommended for interior walls for sound dampening or specific climate-friendly builds.
Production and importation of R-11 (CFC-11), a widely used ozone-depleting refrigerant and foam-blowing agent, were legally banned in the United States in 1996 under the international Montreal Protocol.
Achieving R60 requires approximately 17 to 22 inches of blown-in fiberglass, 16 to 18 inches of blown-in cellulose, or carefully layered batt insulation systems. This substantial depth demands adequate attic space and proper installation techniques.
Mice are curious and always searching for safe, snug, and warm nesting sites. Attics filled with blown-in insulation provide an excellent option–from the mice's point of view. As long as there is a ready food source. Mice are omnivorous and will eat and chew on almost anything including wood and electrical wires.
R-38 insulation is a high-performance thermal barrier primarily used to minimize heat transfer in ceilings, unvented attic spaces, and floors above unconditioned garages in colder climates. It is designed to maximize energy efficiency and maintain consistent indoor temperatures.
R-13 insulation is primarily used to provide thermal and acoustic insulation in standard 𝟐×𝟒 wood or metal framing cavities. It is a standard choice for:
($3.32 /sq. ft.)
It is a common measure adopted by manufacturers, retailers, and even some contractors to ascertain the performance of insulation. Although R-value is important, it will not help you save on your power bills. The fact is, the energy efficiency of your home does not just rely on a number.
Because spray foam can trap moisture, hide the condition of the roof, make it difficult for surveyors to inspect, which means risks like timber decay, dry rot, and not forgetting increased fire risk. If you've got it or you're buying a property that does, this is something you need to know upfront.
The R-value of a 2-inch thick rigid foam board depends on the material type, ranging from R-7.5 to R-13. Because rigid board R-values are cumulative, they provide exceptional continuous insulation for walls, roofs, and basements.
The Amish control mice through non-chemical, self-sustaining methods, relying on active trapping, natural scent repellents, and structural exclusion. Rather than using commercial poisons, they focus on physical barriers and natural predators to keep rodent populations in check.
Potential problems with spray foam insulation
reduce air circulation and ventilation within a roof space. lead to dampness and condensation on the underside of a roof because it forms an air barrier and stops moisture from escaping. place timber-framed roofs at risk of decay.
Closed-cell spray foam and rigid foam board are hard, unattractive to rodents, and double as air barriers. Mineral wool is dense enough to discourage nesting. Fiberglass batts, especially in crawl spaces and attics, are essentially an open invitation.
Should I remove old loft insulation before laying new? Older insulation material will typically need to be removed before adding new insulation. However, in some cases the material may be in good condition, meaning you can simply top up the existing insulation material for a fraction of the cost of a full replacement.
Yes, it's possible to over-insulate your attic, and doing so can create more problems than benefits. Over insulating an attic can block proper airflow and trap moisture. As a result, it can lead to mold growth, wood rot, and compromised structural integrity.
Yes – Eligible R410A Systems Can Still Be Installed in 2026
Short answer: Yes. Eligible R410A systems manufactured before January 1, 2025, can still be installed in 2026 under the Technology Transitions Rule issued by the U.S. Environmental Protection Agency.
R-22 (also known as Freon) was banned because it is a hydrochlorofluorocarbon (HCFC) that severely depletes the Earth's protective ozone layer. Under the international Montreal Protocol and the U.S. Environmental Protection Agency (EPA) regulations, its production and import were banned to prevent harmful ultraviolet radiation from reaching the planet, which reduces skin cancer and cataract risks.
A2L refrigerants, the new refrigerants for 2026, will replace R-410A in new systems. A lot about A2L refrigerants is explained in their name: The “A” means low toxicity. The “2L” is a safety classification, indicating it is mildly flammable.