Choosing the right wall insulation depends on your wall state (open vs. closed), budget, and climate. Base your choice on the material's R-value (thermal resistance), moisture resistance, and acoustic needs.
R19 is technically better for energy efficiency because it provides greater thermal resistance, but it is not inherently better for every situation. The best choice depends on the depth of your wall framing.
Closed cell spray foam is rigid once set. It is a better thermal insulator and was previously sold to stabilise failing roofs. But if it has been used inappropriately or installed poorly, it might put stress on timbers, restrict air circulation and put them at risk of decaying.
The most effective wall insulation overall is spray foam or rigid foam board. They provide the highest thermal resistance (Rcap R𝑅-value) per inch, which reduces heat conduction and seals air leaks.
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.
Insulation materials themselves generally maintain a consistent baseline price year-round, but late fall and winter (November through February) are typically the cheapest times to hire contractors for installation. During these off-peak months, demand drops and contractors are more likely to offer 10% to 25% discounts to secure work.
Neither R-13 nor R-30 is inherently "better"; they serve entirely different functions. R-13 is a thinner insulation designed for standard 2x4 exterior walls and interior rooms. R-30 is a much thicker insulation used in attics and ceilings to prevent heat from rising out of the home.
The healthiest home insulations are natural, breathable materials that are free of VOCs, chemical binders, and off-gassing plastics. Top non-toxic choices include sheep’s wool, hemp, cellulose, and recycled cotton. Unlike conventional fiberglass or spray foam, these materials naturally manage moisture and pose no respiratory or skin hazards.
Yes, mice can chew through and tunnel in rockwool (mineral wool) insulation. While rockwool is denser, fireproof, and doesn't provide nutritional value, its loose fibers and coarse texture actually make it an attractive material for mice to gather and shape into nests.
The cheapest way to insulate walls depends on whether you are doing a new build, finishing a garage, or retrofitting an existing, drywalled room.
Yes, mice can easily chew through foam insulation. Foam lacks structural integrity, and its soft texture makes it a prime target for rodents looking to create nesting tunnels or sharpen their teeth.
The cheapest and most effective insulation overall is blown-in cellulose for attics and fiberglass batts for open walls. Both materials provide excellent thermal resistance (R-value) for their price and are widely accessible for both DIYers and professionals.
Buyers often walk away from homes with spray foam insulation because it can cause major mortgage and insurance denials. The foam tightly seals roof spaces, trapping moisture, and covers up structural timbers. This makes it impossible for surveyors to inspect for hidden rot or damage, which can lead to catastrophic repair costs.
Yes, mice absolutely love blown-in fiberglass insulation. It provides a soft, warm, and highly structured environment for nesting, tunneling, and breeding.
It's recommended to leave an air gap insulation of at least 25mm or 1 inch for the walls and ceilings. This should be enough to allow for ventilation and prevent moisture buildup. The same rule may be applied when using foil insulation. On roofs, the air gap should be larger, typically around 50mm or 2 inches.
R-values rate how well building insulation can prevent the flow of heat into and out of the home. Higher ratings mean greater insulation performance and thus more savings on your next heating and cooling bill.
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.
People remove spray foam insulation primarily because poor installation or improper use traps moisture. This hidden condensation causes severe wood rot, mold growth, and pest infestations. Additionally, the inflexible barrier can strain roof timbers and prevent surveyors from assessing the home's structural condition, which often leads mortgage lenders to reject loans.
Mice have an incredibly sensitive sense of smell, making them highly repelled by strong, sharp, and spicy odors. Their absolute least favorite scents include peppermint oil, white vinegar, ammonia, cinnamon, and cloves.
The primary downsides of Rockwool (mineral wool) are its higher cost, heavy physical weight, and difficulty in cutting. Additionally, during installation, the microscopic spun fibers can cause significant skin, eye, and respiratory irritation.
The Five Most Efficient Insulation Materials
Insulating a 2,000 sq ft house typically costs between $3,000 and $12,000 fully installed. Prices range from $1.50 to $6.00+ per square foot, largely depending on your material choice, whether you are retrofitting existing walls, and if old insulation needs removal.
Yes, you can use R-30 insulation in walls, but only if your wall framing is thick enough to accommodate its thickness. Because R-30 insulation is typically 8.58.58.5 to 101010 inches thick, it will not fit in standard 2×4 or 2×6 walls without crushing it. Compressing insulation destroys the trapped air pockets that give it its R-value, drastically reducing its effectiveness.
Go with R-15 if you are insulating or remodeling an exterior wall in a 2x4 frame and want the best thermal performance. Stick with R-13 if you are on a strict budget, doing interior soundproofing, or if building codes limit your options.
R-30 insulation typically requires a thickness of 8.5 to 10 inches, depending on the type of material you use. Because the thickness needed to achieve this thermal resistance varies by material, checking the exact product specs before buying is highly recommended.