Insulation In An Open Crawl Space
Photo Credit High Caliber Crawl Solutions
This environment has almost the same temperature as the outside air in the winter, which causes the floors of homes to be cold and the rooms farthest from the furnace to be drafty. Unfortunately, as a result of the crawl space sharing the temperatures of the outside air, frozen water lines are an all too often common occurrence in the winter months. In the warmer months, there are often bad odors present due to the shared warm temperatures. Most often these crawl spaces will also be inhabited by various insects and other pests, possibly including a rodent problem. This photo displays the most common environment of a crawl space. You will notice the R-19 insulation typically found in the floor joist cavities. This is required by code in most areas because of the open foundation vents and the problems they cause with energy loss.
Crawl Space Insulation
Crawl space insulation is typically required in most crawl spaces due to the effects of the outside environment, such as temperatures. The primary type of crawl space in which you’ll find insulation is the “open crawl space,” characterized by a standard dirt floor—sometimes partially covered with plastic—and features open foundation vents.
“Open vents” refers to any permanent foundation vent, whether it mechanically opens and closes or not. It should be noted that closing a mechanical vent does very little to keep cold air out. It would be similar to having a window in your home with metal louvers instead of double-pane glass.
What You Should Know About Crawl Space Insulation
Crawl space insulation is meant to keep the conditioned air inside a home from being affected by the cold or warm air in the crawl space. The placement of this insulation, however, can contribute to some other problems. One of those problems is the freezing of water pipes because the insulation blocks off a heat source, the floor, which could possibly prevent the pipes from freezing. The other problem with the install of this insulation is that because most homes have their heating ducts running through the crawl space and the insulation helps to trap the cold air inside the crawl space, this results in the ducts being cooled by the winter air before they reach their destination. The cooling of the ducts causes the furnace to run more often and in longer cycles in order to keep the home at the desired temperature.
Some construction professionals will recommend stuffing some R-30 in the open vents for the winter to keep the winter at bay. This will work and is a very low-cost solution to the threat of frozen water lines. However you may be causing a new problem by doing this. Yes, it is true that the crawl space will be warmer, but it also means that moisture levels will increase inside both the crawl space and inside the home during the cold months. This will add to any moisture problems the home may already have as a result of having an open crawl space. In addition, the insulation stuffed inside the vents will need to be removed quickly in the early spring in order to avoid worsening moisture and/or odor problems.
Unfortunately, having an open crawl space often means that anything done to correct one problem will most likely cause a different problem to develop or worsen. Our recommendation is to learn how to encapsulate your crawl space. Crawl space encapsulation is the process of sealing your crawl space off from the moisture outside, and this process is actually the only way to truly control the crawl space environment.
