Building Homes or Extensions/Insulation under cement


Should I put insulation under basement cement on a new home construction ?

If the basement floor is below grade no insulation is required; the earth maintains a temperature around 55 degrees below the freeze line.  However, insulation on the basement walls is a good idea.  You can buy rigid foam 4x8 sheets in various R-values.  They come with a protective film on the exterior side to prevent insect damage and repel water from coming in contact with the foundation.

If the basement slab is at grade it is advisable to place vertical insulation at the slab edge and horizontal insulation at the base of the slab extending outward from the bottom of the slab.

There are various rules in the codes as to how foundation walls/slabs should be insulated and they vary depending on a variety of factors.  If you have a building permit requirement in your location the plan review or permit issuing office can tell you what the requirements are.  Also, most foundation contractors and many insulation contractors will know what is allowed in the local areas.

Good luck.

Len Kroll
Wood House Log Homes LLC

Building Homes or Extensions

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Len Kroll


I can answer questions concerning log home design, manufacture, construction, maintenance/repair, restoration and insect control in log homes. I can also answer questions pertaining to wood properties, characteristics and performance as they relate to log home applications. Additionally, I can answer questions pertaining to residential construction and repair, some engineering and trade issues.


I have been in the log home and construction industry for 38 years, 10 years in a specialty contracting field and 28 years in the log home field. My company has designed, produced and supplied over 3,000 log homes and built over 500 and restored over 600 during that 28 year period. I was a volunter in AllExperts for several years and somehow fell off the map. I answered hundreds of questions during that term and had a very high rating.

I authored a monthly column in an in house publication expressing the Vice President and General Manager's "Observations and Insights" which was distributed to approximately 300 employees and management.

I have a BS Accounting degree from the University of Illinois, 1963, and a Master of Business Administration degree from the University of Chicago, 1968. I have participated in numerous relevant seminars over the years including an intense two week broad business administration seminar at the University of Pennsylvania Wharton School of Business, 1978. I have participated in the National Association of Home Builders Graduate Builders continuing education program.

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National Honor Society Student, Illinois State Academic Scholarship, Dean's List

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