What is a conditioned crawl space and why should I demand one?

Were you ever afraid to go in the closet when you were little? It was dark, scary, and most certainly contained every foul monster your imagination could conjure up. As you grew up, you came to realize that the scariest thing in your closet was that jean jacket you used to wear back in college. In fact, you came to love the closet for all of the storage space it contains. There is, however, another place in your home that is dark, scary, and may certainly contain some foul monsters: the crawl space.

Your typical ventilated crawl space is a very inefficient space. It consists of compacted dirt under your home and possibly houses bugs, snakes, spiders and even small animals. Worse yet, the stale, moldy crawl space air can wreak havoc on the air quality inside your home as it slips through little cracks and gaps in the floor. This also causes your utility bills to increase significantly. In fact, in heating-dominated climates such as Idaho, 40% or more of the air you breathe in your home originated in your crawl space.¹ In essence, you are paying to breathe stale, moldy air that can be harmful to your health and budget. Not a good trade off.

On top of this, moisture tends to collect in a traditional ventilated crawl space. During the harsh changes in climate during the summer and winter, the moisture content under your home increases and condensation can occur. As you may know, moisture and your wood house don’t mix. The result? A moldy and rotting mess!

So why keep building these inefficient and dangerous ventilated crawl spaces? Thanks to some breakthrough research and testing in the past few years, builders have discovered a way to significantly improve the efficiency of a crawl space in your new home in Idaho.

Why a conditioned crawl space is the only way to go

A conditioned crawl space, also known as a sealed, unvented, or closed crawl space, significantly reduces or eliminates many of the problems of the traditional ventilated crawl space. It does this by allowing conditioned air from your home to flow through it in a sealed space, which then vents the used air to the outside of your house. Think of it as a mini basement under your home. Not only does a conditioned crawl space significantly improve the air quality in your home, it reduces your heating and cooling costs, keeps your crawl space dry so it doesn’t attract mold or rot, and provides a nifty place to store Christmas presents.

How can something as simple as circulating air from inside your new construction home into the crawl space do all of that? Let’s delve into the details.

How it works

In a typical Tresidio home, the crawl space is lined and sealed with a durable polyethylene barrier on the ground of the crawl space and up the walls of the foundation. This stops moisture, spiders, snakes, and anything else from getting under your house (did I mention that it stops spiders from getting under your house?).

Once the barrier is installed, insulation is applied to the foundation walls, providing protection from the weather outside. This stops cold or hot air from seeping in through your floors, saving a lot of money in heating and cooling costs. As an added bonus, it makes stepping on hardwood floors with bare feet much more comfortable during the cold months of the year.

The heating and cooling system of the home is then set up to push the fresh air from inside your home down to the crawl space. This air is much drier than the air outside the home, and therefore helps prevent mold and rot. A fan that is constantly running then pushes that used air outside the home, completing the cycle.

Taking back the crawl space

Just as we eventually learned to not be afraid of the closet and eventually embrace it, the same must happen with the crawl space under our homes. Significant advances and research in sealed crawl spaces have won back the crawl space as an efficient and safe space. When building a new home, make sure you choose a builder that knows you want to utilize a conditioned crawl space.

¹http://homeenergy.org/show/article/id/776/viewFull/