How to Insulate Basement Walls

Benefits of Insulating Basement Walls

The obvious benefit of basement wall insulation is the substantial energy cost savings it should provide. However, your savings will depend upon the following factors: local climate, type of heating system, fuel cost and lifestyle of the people who use the basement.

Ultimately, the thermal performance of any insulation or any combination of insulation depends upon proper installation, which is why it might be a good idea to hire a professional contractor who has a lot of experience with basement wall insulation. The most cost-effective way to insulate a basement of an existing structure while minimizing moisture problems involves a combination of rigid foam insulation and an insulated frame wall assembly.

It's all about airflow. Experts talk about the importance of "inward drying," meaning the foundation's ability to disperse moisture into the basement, allowing it to dry. Restricting airflow causes moisture to be trapped. A true vapor barrier, used to block moisture from coming into the basement, often succeeds in trapping the moisture between the insulation and the wall. If the insulation is installed on a wood wall frame and encased in a vapor barrier like polyethylene sheeting, the moisture will be trapped inside, which will damage both the insulation and the wood frame.

Now that you've learned the basics on kinds of insulation, tools, materials and benefits you should be ready to start your basement wall insulation project and watch those energy dollar savings add up each year. To learn more, visit some of the links on the following page.

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