X-post: Insulate floor or not?

[curtisc63]

Sorry for the X post but decision time is drawing near and I am not sure the topic is better here or in the General forum:

We are building a new home here in the Baltimore MD area. The garage is 34 X 27'. I am going to fully insluate the garage for more year round use. I do not plan on heating the garage floor. Would you recommend insulating the garage slab anyway? If so, would you also do a thermal break foam around the perimeter?

I just wonder how effective it would be if we are not heating the floor. I have quotes for 1" foam board (R5) at $1200 and 2" (R10) at $1700.

Thoughts?

Thanks.

CC

 

[t. jones]

I did my floor with no insulation and in floor heat, crushed stone provides thermal break http://www.garagejournal.com/forum/showthread.php?t=46747
I read on one of the in floor heating sites where they had trouble with insulation breaking down over several years and didn't recomend it.
Thanx Trevor

 

[MN BIANCHI]

I do have some experience with under slab floor insulation. Most of my properties do not have any under slab insulation. I do have 2 buildings that have under slab insulation. There is a noticeable difference. The garage floors that do not have insulation are obviously cold in the winter, but they are also cool well into the summer. In the spring of the year as soon as we have a high humidity day the cool concrete will start to sweat from moisture condensing on the cool surface. The floors with under slab insulation do not have that problem even if they are not heated.

The building I an currently constructing has in-floor heat in the shop area and a couple more rooms. The "Cold Storage" side of the building is fully insulated, but not heated. The entire building has perimeter insulation and under slab insulation. Of course I do live up North were it does get COLD. It was 33 below on Sunday. If I lived in a warmer climate I might have to evaluate the cost benefit ratio, but for me it is a no brainer.

This is a link to my build: http://www.garagejournal.com/forum/showthread.php?t=46240

 

[curtisc63]

Thanks for passing on your personal experience. One of the main reasons I wanted to do this was to try and prevent the spring condensation you mentioned. I hate when that happens. I feel like I have to try and dry everything and always wonder about what I am missing or doing to electronics...