Replies

1. GBA Editor
   Martin Holladay | Jul 15, 2015 02:41pm | #1

   Peter,
   I'm sorry, but I don't understand your question. I'm guessing that you want to ask something like "Is it possible to build a house without caulk?"

   Or maybe "Where should I use caulk?"

   Or maybe "How many tubes of caulk should I buy?"

   Or maybe "Will my tubes of caulk be damaged if I store them in a location subject to freezing?"

   Or maybe "How do I clean my fingers after I use my fingers to smooth a caulked seam?"

   But if you aren't more specific, it's hard to guess what you want to know.

2. 
   user-4145989 | Jul 16, 2015 10:42am | #2

   Sorry for the lack of specificity.
   Is it necessary to caulk the inside and outside of the foundation plate if I am spraying closed cell insulation on the interior framing covering the plate.
   Also, how do I clean my fingers after I use them to smooth a caulked seam?
   Thank you in advance.

3. GBA Editor
   Martin Holladay | Jul 16, 2015 10:57am | #3

   Peter,
   Q. "Is it necessary to caulk the inside and outside of the foundation plate if I am spraying closed cell insulation on the interior framing covering the plate?"

   A. By "foundation plate," I'm assuming you mean the pressure-treated mudsill. (At least that's what we call it here in New England.)

   If you are building a home with a basement or a crawl space, it's possible to cover the crack between the mudsill and the foundation wall with interior spray foam. However, that's not enough for a good air seal. At a minimum, you want to install foam sill-seal between the foundation and the mudsill at the time when the mudsill is installed. After the house has been framed, providing some weight on the mudsill, it's usually a good idea to caulk this crack on the interior for an improved air seal. Alternatively -- a more expensive but better option -- the crack can be sealed with a high-quality European tape like Siga Wigluv.

   Then, after the caulk or tape is installed, a little spray foam in addition never hurts.

   If you are building a home on a slab foundation, I doubt if you will want to cover the crack between the mudsill and the slab with interior spray foam. In this case, just like the house with a basement, I recommend foam sill seal and (later) caulk.

   Q. "How do I clean my fingers after I use them to smooth a caulked seam?"

   A. Use an old T-shirt dampened with a little water or a damp paper towel.

4. 
   user-4145989 | Jul 16, 2015 01:12pm | #4

   Can I use the Siga Wigluv to seal the exterior between the mudsill and top of foundation?
   Thank you for your continued advice.

5. GBA Editor
   Martin Holladay | Jul 16, 2015 01:31pm | #5

   Peter,
   Q. "Can I use the Siga Wigluv to seal the exterior between the mudsill and top of foundation?"

   A. Yes.