Replies

1. GBA Editor
   Martin Holladay|Aug 17, 2015 09:41am|#1

   Esther,
   I don't think you need to worry about the passive solar performance of your basement slab. Unless you have a walkout basement with floor-to-ceiling windows on the south side, it's hard to imagine that you'll end up with much glazing area in your basement. Heat storage will be marginal in any case.

   If you want a warm slab, the most important thing you can do is to install a continuous horizontal layer of rigid foam insulation (at least 2 inches thick) under your slab. Don't worry about your windows.

   If you want to install linoleum or sheet vinyl flooring, make sure that the slab has cured and that the concrete has a low moisture content before installing the flooring. Remember, some flooring manufacturers do not allow their products to be installed on below-grade slabs -- so do some research before you choose your flooring. A dark-colored flooring is more likely to absorb solar heat than a light-colored flooring.

2. 
   Charlie Sullivan|Aug 17, 2015 09:58am|#2

   I don't think that linoleum will affect the thermal behavior of that system siginificantly. On the other hand, I don't think it would offer much cushioning. Perhaps consider a layer of soft solid rubber between it and the concrete. Foam cushioning would insulate but solid rubber wouldn't insulate much. I think it's more of an aesthetic choice than anything else. Your shoes will probably have more cushioning than the floor.

3. 
   Esther Streusand|Aug 17, 2015 10:05am|#3

   Thanks for the swift guidance, Martin! I'm with you on the slab insulation and the flooring research.

   I should have said - it's a partial walkout with about 70 square feet of south-facing glazing for about 1,100 square feet of basement.