10 Things You Need to Know about Floor Insulation Options
Insulating your floor can keep you from losing up to 20% of the heating or cooling in your house. Take a look at these 10 things you need to know about floor insulation options.
1. Makes You Warmer, just not your feet
Remember that your no matter your choice, that it is something that is a barrier between different temperatures than something that generates warmth. So while it keeps your home warmer, it doesn’t always make your floor feel warmer to the touch.
2. Check the R Type rating
Floor insulation is rated with an “R Type”. The R Type is a standardized rating that is determined by the thermal barrier it represents. The higher the R Type the more it insulates. For more information see energy star guidelines for full requirements.
3. There are Two Types Of Insulation
There are two main types of floor insulation. Under floor insulates between an unheated lower space and the room above. Above floor insulation is placed between the subfloor and the actual flooring that is put into the room.
4. Install a Vapor Barrier
Your insulation must incorporate a vapor barrier of thin plastic to help prevent moisture from getting into the flooring from below, and in places like the kitchen or bathroom from the moisture getting through the floor to the insulation below. Moisture can ruin the insulation by compromising it, and insulation can cause moisture to be retained and cause wood rot.
5. Concrete Slabs Are Different
If you are thinking about basements and concrete flooring the thermal loss is mainly on the edges of the slab and not through the bottom. It is often much more useful to insulate the edges of the concrete slab. Concrete insulation is normally placed within the concrete itself for maximum effect.
6. Heated Flooring Needs Help
If you have a heated floor it has to be insulated so the heat created radiates into the room and not into other spaces or down into the ground. If you don’t you are losing money each time you turn it on.
7. Below Floor Options
Rolls and Bats: This type of insulation is what most people think of when thinking about insulation. It comes in large rolls, often with a paper backing. Rolled insulation is one of the worst type to use on your floor. The difficulty with rolled insulation is keeping it in place without compromising the insulation itself. Gravity always wins in the end and the insulation falls away from the floor, even if just slightly. Once this occurs the insulation is worthless. Your rolled insulation must fill the entire space.
Loose fill: Loose fill insulation is blown into place and fills the area. This requires something to retain the loose fill insulation in place. Either boards or plastic sheeting must be put under the floor joists to retain the loosely blown insulation in place. This type of insulation works better, although with settling an inevitable fact it can become compromised over time.
Rigid foam: Rigid foam boards provide good insulation and are able to be worked like other building materials. Normally used in either new construction or renovations, rigid insulation is cut to fit in between the joists of the flooring, and the edges sealed with caulking or spray foam insulation.
Spray Foam: Spray foam insulation is likely the best option for below floor insulation. The most expensive option. It is the longest lasting and the highest R value insulation that can be put into place. Foam in place insulation is sprayed into spaces between the joists and goes around venting, pipes, and electrical work.
9. Above floor options
Cork: If you want to be environmentally friendly, cork is a good option. Cork can be cut into thin pads to go underneath the flooring material. This provides sound, thermal, and impact insulation.
Padding: A thin pad of around 1/8” is often placed below floors to give them some sound insulation and thermal insulation. This pad is put down and then the floor is placed on top of it, this can be used for standard installations and floating floors.
10. No Such Thing As Perfection
Your floor insulation will never be perfect. It is very rare for a floor to be able to reach the highest energy star rating. If you spend $1000 to get $50 off of your heating/cooling bill it will take 20 years to recoup that cost, by which time you will have had to replace it. Make a choice that makes sense in terms of cost to benefit achieved.