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Insulated Crawl space


Insulation materials with a higher R-value help you stop heat loss and keep out cold without sacrificing comfort.

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Having an open crawl space under your home will make it colder in the winter than it would be if it were built on a concrete slab foundation. An open crawl space also makes it easy for mold and mildew to grow in it and cause problems. To protect your crawl space, you have to install adequate insulation with the recommended R-value. 

This leads us to the question, “What is R-value, and how does it impact the temperature in your home and its crawl space conditions?” If your home was built 10 or so years ago, its insulation levels are likely lower than those recommended today for comfort and energy savings. 

Insulated Crawl space

Understanding R-Value 

R-value is simply the measure of how well an insulation material can resist heat, which is essentially the key to preventing heat loss. The greater the R-value, the greater the heat resistance and the better the insulation. The R-value varies depending on the density, thickness, and type of insulation used. 

Crawl Space Insulation Types 

Insulation materials have varying R-values. When insulating your crawl space or other parts of your home, you ought to consider the R-value of the insulation. Here are some common insulation materials: 

Roll: This material is made of glass fibers and comes in wide, puffy sheets. It’s suitable for insulating long and open areas like the space over attic joists. 

Batting: It’s made of glass fibers and puffy strips with or without a paper or aluminum face. This insulation is suitable for covering walls, attics, and the space between joists. Flattening or compressing battling reduces its R-value. 

Blown-in: This insulation type is made of fiberglass or loose cellulose. It’s blown into attics and walls with no previous insulation. What’s good about this insulation is it easily fills around odd cavities and shapes. 

Spray foam: Made of expanding polyurethane foam, this type enlarges and cures into the shape it’s sprayed. It’s used to insulate pipes and wires and where batting can’t be used. Spray foam has an R-value of 6.3 and low-density. 

Rigid foam: Foam board is made from expanded or extruded polystyrene and has an R-value between 3.6 and 4. It has a smoother surface and excellent thermal properties. This material is usually tucked over the crawl space and basement and provides an effective vapor barrier. 

What’s the Best Insulation Product? 

A good insulation solution is supposed to be non-flammable, compact, and effective in slowing down heat transfer. It should also deter pests and not harbor mold. 

When insulating your home, be sure to check the R-value requirements in your region. Your local contractor will advise you on what works best. For the crawl space and basement, we recommend ExTremeBloc™, which combines expanded polystyrene, graphite-infused insulation, and a radiant heat barrier. This potent combination provides the crawl space wall with a formidable insulation with an R-value of 11. 

Identifying and Covering Under-Insulated Areas 

Aside from the vented crawl space, there are many key areas in the home that are either uninsulated or under-insulated. These areas allow cold air to infiltrate your home, meaning you’ll use more energy to create a comfortable indoor environment. Pay special attention to your: 

Crawl space: Inspect the perimeter walls if crawl space is vented and the space between floor joists if the crawl space is unvented. Soft materials like fiberglass are not ideal for crawl spaces, as they can easily hold onto moisture and harbor mold and pests. Use rigid ExTremeBloc™ instead for the best protection. 

Attic: Slide a tape measure into the current insulation to determine its depth. It needs to be 19 inches deep. In most places, the attic needs insulation with a higher R-value than the basement or crawl space. This may mean adding another insulation layer to the existing material. 

Basement: Inspect your unfinished basement walls and rim joists. Be sure to compare their depth against the R-value map for your region. Cover the drywall then use a fiberglass batt to insulate the area between the floor joists and the room above. 

Knee walls: Check this area, which lies between the living area and your garage/attic. If your home is more than 30 years old, it might not have effective insulation. Get a professional to apply blow-in insulation to reduce heat loss. It will make the indoors quieter and more comfortable too. 

Floors: Insulating the floors over unheated basements or other areas will make the room comfortable. Use mineral wool batts or kraft-faced fiberglass on the subfloor. Measure the floor depth before you walk into a store. You will probably require six- to eight-inch-wide panels. 

Why Insulate Your Home? 

Insulating your home provides several benefits beyond comfort. A properly insulated home provides: 

Lower utility costs: Insulating your home and areas like the crawl space ensures your living space stays warm in winter and cooler in summer, which reduces your cooling and heating costs. 

Noise reduction: Insulation materials also make good soundproofing materials. They absorb unwanted noise and sound from your appliances or audio equipment, making your home quieter. 

Enhance energy efficiency: To make your home more energy-efficient, you need to insulate the floors and the exterior walls that separate the conditioned areas from the unconditioned ones. Insulation helps prevent heat leakage around openings and fixtures like door frames, windows, and the entry/exit points of pipes and wires. 

Moisture control: Daily chores such as washing, bathing, and cooking release significant amounts of moisture to the indoor air. This vapor often gets trapped on the walls, leading to mold or mildew growth, which are a health concern. Insulation creates an effective barrier against such moisture.

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