Replies

1. 
   Patrick_M. | Jan 06, 1999 02:54am | #1

   *
   Dear Bill

   I'm a firm believer in insulating the exterior of concrete walls if at all practical because you then get to use all that concrete as 'thermal mass' which will help to moderate interior temp. swings in heating season, especially in Spring & Fall. You should know, however, that unless the basement has gaping holes in that it is the last place where you should spend your insulation $$. The heat loss out of a reasonably tight basement is minimul when compared to other potential trouble spots elsewhere in the house.

   2" of Expanded Styro would get you R10. It's easy to apply and flash, but I do believe Dow abandoned their own stucco product some years ago so you would have to apply expanded metal lath and then the requisite coats of stucco. Some others on this board may have more up to date suggestions/products for this application.

   Have fun

   Patrick

2. 
   Guest_ | Jan 06, 1999 04:48am | #2

   *
   Just make sure that you use a foundation coating that is polymer based so as not to eat up the XPS!

1. 
   Guest_ | Jan 08, 1999 02:47am | #3

   *Bill. For some reason it is not clear to me that the 11-inch thick walls you mention are you foundation walls or the above grade exterior walls.Which?Researchers at University of minnesota found only a small difference inperformance between foundations with rigid foam board insulation (RFBI)on the exterior, or on the interior. Ideally the RFBI should be on the exterior because it acts as a buffer between the earth and the foundation. HOWEVER :-} termites can and do get between the foam and the foundation walls. The October 1998 issue of the Journal of Light Construction published an article, "Insect Infestations in Buried Foam." I'd think very carefully about exterior RFBI.Gene L.

1. 
   Guest_ | Jan 08, 1999 05:28am | #4

   *Bill,If your walls are above grade, you might look into EIFS, like Dryvit. There are many different brands. In addition to seconding Gene's advice about termites, which, depending upon wher you are building, could be very important, I would offer one other point. If you go with any exterior insulation foam and stucco system, or any synthetic stucco system, regardless of manufacturer, make certain that the applicator has been to the appropriate mfr. school and is authorized to use the material. The most dependable way to do this is to call the manufacturer rep and ask who in your area they would recommend. Then make sure the work conforms to the mfr. recommendations, especially as regards priming, weather conditions (this is important),and at potential drainage-plane problem areas, like under windows or at intersections of surfaces.EIFS has gotten a bad rap. The industry proposes that a lot of the problem has been faulty installation or application practices. I tend to agree. It can be a good system if it is used properly for appropriate applications.Please let us know what you decide on and how it works.

3. 
   Sacie | Jan 08, 1999 09:07am | #5

   *
   Gene, I would be very interested in knowing more about the Univ. of Minn study that suggests foam board on the interior or exterior makes little difference. CAn you site the information for me? Thanks, Sacie Lambertson

4. 
   Bill_Bazata | Jan 08, 1999 09:07am | #6

   *
   My 2 story house has 11" thick poured concrete exterior walls. It's been cold here in Northern Indiana for about a week now and the exterior walls are uncomfortabley cold to be within a few inches of. My gas fired boiler(1991) and radiator(1922) system is haveing trouble keeping the house above 60. There are lots of ways for me to tighten-up the house durring my renovation, and I hoping there is a solution to my cold walls. Should I insulate on the inside or the outsinde of the walls? The outside needs repair and painting, and I'm considering resurfacing. What about an exterior system of foam and a stucco like skim material (I forget the trade names)? How mush R-value can I hope to get and how will this effect the cold wall feel?