Energy Savings

With today's higher energy bills it only makes sense to look at ways to make our homes more comfortable and efficient. We know adding insulation to the attic, replacing old drafty windows and doors will make a huge impact to the energy efficiency of a home. But, did you know that encapsulating and conditioning your crawl space can save you around 25% on your heating bills? That's another huge savings, not to mention your home will be more comfortable. Michigan winters are very cold and when that cold air is allowed to enter the homes envelope (through the foundation vents) it costs you more to keep it warm. There is a better way, instead of trying to protect your home from the crawl space we change the environment so that you are protecting your home (including the crawl space) from the outside, just like a home with a basement.

 

Insulating your crawl space, like the rest of your home, on the exterior walls will keep the cold air out and the warmer temperatures in. Or, in warmer temperatures, keep the hot air out and the cool air in. Of course this does not work if the foundation vents are left in the wall. Even if the foundation vents are closed they offer little resistance to the temperature difference between inside and outside. Part of the environment change is to remove the foundation vents and install a cement block, this allows the insulation to run continuously around the foundation. Once the foundation walls are insulated there is no need for insulation in the floor joists (crawl space ceiling) and if there is any it will be removed.

 

International Residential Code (IRC) Citations allowing for a closed and conditioned crawl space-

 

IRC 2006, Section 408.3 Unvented crawl space-

 

Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where:

1. Exposed earth is covered with a continuous vapor retarder.
2. One of the following is provided:

2.1 Continuously operated mechanical exhaust ventilation at a rate equal to 1.0 cfm (0.47 L/s) for each 50 ft² (4.7 m²) of crawlspace floor area, including an air pathway to the common area, and perimeter walls insulated in accordance with Section N1102.2.8.

2.2 Conditioned air supply sized to deliver at a rate equal to 1.0 cfm (0.47 L/s) for each 50 ft² (4.7 m²) of under-floor area including a return air pathway to the common area, and perimeter walls insulated in accordance with Section N1102.2.8.

2.3 Plenum complying with Section M1601.4 if under-floor space is used as a plenum.

International Energy Conservation Code (IECC)

 

IECC 2006, Section 402.2.8 Crawl space walls-

 

As an alternative to insulating floors over crawl spaces, crawl space walls shall be permitted to be insulated when the crawl space is not vented to the outside [excerpt].

 

Source for IRC and IECC- http://resourcecenter.pnl.gov/cocoon/morf/ResourceCenter/article/131