G2G Insulation Twin Falls
Home Improvement

Insulating Your Home
from the Bottom Up

Insulating your home is an event you need to take time to evaluate and understand. Take the time to understand the mechanics and purpose of insulation; basically the why you are spending the money to insulate your home and the benefits of what you are doing. Believe it or not, there are times and geographic locations where insulating your home is counter productive; a waste of money to purchase and install the insulation and when you do buy the insulation and install it all you are doing is blocking the heat you want or the coolness you need.

The biggest mistake most people make is to insulate a full basement in any climate condition, especially if your home is equipped with a multi story basement.

This is uncommon because of the expense, but an increasing number of up-scale homes are being built on a full basement with a “half basement” above it (partially backfilled so the home is elevated) or they have a true two story basement. If you are planning on this type of construction do everything you can for an external vapor barrier to keep the water out, but do not use any material for the purpose of insulating your basement from temperature changes.  Even with a single basement you will have a heating and cooling advantage by simply using the natural earth.

Even in the coldest places in Alaska or northern Canada the ground will only freeze about 5 feet down. Knowing this information with your specific location in mind, maybe you will want to insulate the top 5 feet of the pour of your basement, but anything that is below the freeze level is a heat source.

In a cold weather environment you do not want to insulate any heat source no matter how minimal it is. The same goes for a hot weather environment. In the desert your basement is cool. Why would you want to insulate against a source of coolness when it is 105 degrees plus in the shade outside?

A major factor of insulating your home is airflow. In a very hot environment you want it and in a very cold environment you don’t. In an environment that is both hot in summer and cold in winter you need to be able to control your airflow for the purpose of insulation and insulating your home.

This is not true in all cases, but homes built in damp or wet areas that freeze in the winter are normally built with elevated wood floors, while homes built in warm climates are usually built on concrete slabs. Concrete slabs are quicker, less expensive and superior in quality to elevated wood floors, but they do not stand up very well over time in an environment that is subject to the expansion and contraction of freezing and warming.

One way to help a concrete slab and even your foundation is to lay a 4 inch thick Styrofoam layer in the ground and position on each side of the foundation. The same goes for a slab, it is just a bit pricy.

For a raised wood floor airflow is as important as physical insulation. Even with no insulation under your floor, if you can stop the airflow under your home you will see a noticeable decrease in the amount of heat loss.

Raised floors are very easy to insulate using Styrofoam. You simply need to find used or discarded scraps of Styrofoam (or buy new if you can afford) and install them between your floor joists from the bottom. All American homes will have floor joists that are at least 6 inches thick, but that is more insulation than you technically need.

4 inches of Styrofoam will give you an insulation R Value of at least R-20 (Styrofoam has an average R Value of R-5 per inch) and 6 inches will give you R-30. The trick is to make sure the Styrofoam is held tight against the bottom of the floor.

You can do this by installing more Styrofoam than the thickness of the floor joists and holding them in place with straps or strips of plywood or if you do not have access to enough well priced or free Styrofoam you can insert scrap wood between the strips or straps to hold the Styrofoam snug to the floor.

The way you do it is your choice and will probably be determined by the cost of your source of Styrofoam. Used or discarded Styrofoam is very inexpensive. New sheets of Styrofoam are very expensive.   


When to insualte your home