Text to Order!There are multiple ways you can insulate the floors of a home, so you will have to base your insulation method on
- Your local climate
- Type of floor
- Age of the home
Generally, you will need to place your insulation between the joists of the floor, and, depending on your floor, this can be applied either from underneath in the crawlspace or from above by lifting up floor panels. You can use cellulose insulation, wood-fiber insulation, or other alternatives based on your type of flooring.
Whether you’re looking for temporary fixes, or are planning to hire a licensed professional for this work, below you’ll some effective and even cheap alternatives to protecting your home against winter chills and heat loss.
When you’re preparing to insulate your crawl space, you need to take into account your local climate and take a peek under your house. The condition of the insulation here will clue you in to your need for insulation: Damp, hanging insulation is a red flag and a sign that your insulation is outdated and in need of replacement. Check on the laws that apply to the area in which you are working:
The U.S. Department of Energy currently recommends insulation with an R-value of at least R-9 in floors. This is important to know, especially for homes that were built in or before 1990, as these homes may not have any insulation at all (it wasn’t required).
In moderate or dry climates that do not pose the threat of sustained freezing temperatures, it is best to install insulation between floor joists. Where the winter temperatures are extreme, it is better to opt for insulating the walls and sealing off the crawlspace entirely.
Six-inch R-19 fiberglass batts that are installed between floor joists, along with moisture control and mold prevention, will be best for winter climates with temperatures that do not drop below freezing.
Steps for Insulating a Crawl Space for Moderate Climates
- Calculate the ventilation your crawl space will need and cut in new vents as necessary. Use spray foam insulation to seal any holes for electrical wiring and plumbing.
- When using fiberglass batts, they should be unfaced and installed so that they are in contact with the underside of the subfloor.
- Place wood lath every 18 inches or a crisscross webbing of wire for reliable batt support. Avoid stay rods (also known as tension rods). These compress the fiberglass and lessen the value of the insulation and can come loose.
- Lastly, you’ll need to insulate the plumbing pipes and HVAC ducts to prevent heat loss and freezing.
Older homes will be a bit trickier to insulate because standards from decades ago were extremely different standards for architecture and home structure. The floor is one of the places in the home where a significant amount of heat escapes, whether directly into the ground or through a cold cellar located beneath.
Not only does it make the home itself much colder, but it also makes the floor uncomfortable to walk on. Proper insulation can improve the efficiency of the flooring, allowing it to hold heat in for longer periods of time and protect your home from moisture.
Floors are constructed in two ways: they are either suspended or solid. Suspended floors consist of floorboards nailed to joists, which are often carried on “sleeper” walls of brick.
- For suspended floors, it is essential that the underside of the floor is ventilated to avoid the collection of moisture. For these floors, grilles are incorporated at the base of the walls to allow for a cross draught.
- Solid floors, on the other hand, many of which are brick, tile, or stone, used to be laid directly onto the soil, sometimes lined with a bed of lime mortar or sand underneath. Because of this, these floors can be quite cold to the touch and difficult to insulate.
Steps for Insulating a Suspended Timber Floor
When insulating a suspended floor, the two priorities you must keep at the forefront of your mind are the improvement of thermal insulation and draughtproofing. Having access to the floor from underneath via a crawl space or cellar will make the insulation process easier.
The best way to insulate a suspended floor is to push quilt-type insulation between the joists from below. This will be supported by plastic garden netting, and additional insulation can be provided by the tongue-and-groove wood-fiber board by fixing it to the undersides of the joists.
If you don’t have a crawl space or another method of reaching the suspended floor from underneath, it is still possible for you to add insulation, but it will just require a little more creativity. You will have to lift the floorboards, a few at a time. Lay garden netting over the joists to form troughs and lay quilt insulation between the joists to fill the spaces.
You can also use a breathable membrane and then fill the troughs with cellulose insulation, or use foil-faced foam or wood-fiber insulation board between the joists supported on timber batts.
It is especially important with wood floors to protect against excessive moisture, because wood, as you know, warps when exposed to too much water or water vapor. Because of this, creating and maintaining a vapor barrier is vital to the integrity of your wooden floor.
Unfaced batts are the best for use on wooden floors because this type of insulation doesn’t have rigid ends, but it is harder to keep up. Any loss of integrity will damage the water vapor barrier and weaken the vapor barrier and expose the floor to ground moisture.
The batting can be held in place with thin metal rods known as “lightning rods.” You should space the rods evenly, 18 inches apart to hold the insulation in place. You can also use plywood or lattice boards, but it is debatable whether the increased price is worth the slight improvement in quality. It is not suggested to use netting for the insulation of the wooden floor.
How to Go About Insulating Your Floors
When you are planning to insulate your floors, it is important to recognize that, although there are many DIY options to insulation, it is vital that you plan ahead and have the correct safety equipment. This is because there are many aspects that go into the planning and execution of an insulation project, having to take into measurements and calculations, age of the home, local building laws, and much more.