Some difference of opinion has been aired in recent years over the venting of crawlspaces. One line of thinking is that ventilation reduces moisture, and for that reason building codes sometimes require it. The opposing point of view is that open vents might actually create moisture problems in homes that don’t have proper moisture control or drainage techniques. Open vents tend to make it difficult to keep a crawlspace warm in the winter, and in the summertime they can really bring in the humidity.
Your decision to vent or not to vent will have a direct impact on your next decision, which will be whether or not to insulate (or install additional insulation). Insulation tends to reduce some of the problems of unvented crawlspaces, and you won’t need much if the area is sealed, but be aware of some potential drawbacks. It may be damaged by water, rodents or other pests, and it could interfere with a radon mitigation system.
Before taking on the insulation project, be sure that the crawlspace is airtight and that access is sealed. Check on any pest-control issues and building code compliance, and make sure that any equipment such as furnaces or water heaters in the space are sealed-combustion units. We would recommend having a professional ensure that your crawlspace is properly sealed and insulated.
On the dirt floor use a polyethylene vapor retarder or similar material, and you might want to protect that and keep it in place with a thin layer of sand or concrete.
Learn more about how to protect your home and at the same time improve its comfort level by contacting the experts at Ernst Heating & Cooling.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information, click here to download our free Home Comfort Resource guide.