Replies

1. GBA Editor
   Martin Holladay | Sep 17, 2011 12:32pm | #1

   Rich,
   I would be inclined to use a robust rubber or butyl membrane as a capillary break, as the BSC website advises -- something like EPDM roofing or butyl. If you want to shim up your house, it's easy enough to add a new 1x8 or 2x8 pressure-treated sill on top of the rubber membrane.

2. 
   jnarchitects | Sep 17, 2011 01:15pm | #2

   Hi
   I was just at a Building Science seminar last week and Joe described jacking up his antique house one inch to slide a piece of ice and water membrane in b/w the top of the rubble wall and the sill around the perimeter of the house. He did this may years ago and has had no issues. His only mistake he said was not turning up the outside edge of the membrane onto the sheathing and then counterflashing with the building wrap.

3. 
   user-939142 | Sep 17, 2011 03:36pm | #3

   "His only mistake he said was not turning up the outside edge of the membrane onto the sheathing and then counterflashing with the building wrap."

   could you explain further?

   does the ice and water shield membrane wrapped around the wood sill?
   i guess this would help shed water if the outside lip turned up over the sill and you could put building wrap and flashing over it.

4. 
   user-939142 | Sep 17, 2011 03:43pm | #4

   i would use the tired an true pressure treated wood in this case. no need to be the experimental lamb on this, and Azek is not cheap especially in a size to cover a foundation wall width.

   you would still want and ice and water shield like membrane that can wrap and adhere.
   in my plans to do this i have the water shield wrap the wood sill, and a sill membrane underneath to help fill in some of the gaps as the fieldstone is not perfectly smooth (you could try to patch and smooth it out but the 1inch gap doesn't leave much to go with. i also plan on using a metal termite shield and lots of appropriate caulk as air penetration and water penetration is important too.

   the epdm gaskets look ideal too

   a better idea for experimenting if you want to be risky and green would be installing something more thermally broken like a high psi 1" foam plank or similar.

5. 
   richmass62 | Sep 17, 2011 07:22pm | #5

   Thanks to all... Ice and water shield sounds good.

   Bob, what climate zone are you in? I am wondering how much I have to worry about termites here just south of Nashua nh. The bigger issue for us is mice and files -- they love the gaps under the sill, and also under the vinyl siding.

   Termites can be controlled by a pest control service.

   Carpenter ants are perhaps the biggest concern because the chemical that stops the termites only is effective against ants for a year or so. So does your metal barrier do anything to stop ants? And would termites be more likely to enter a house by burrowing under the foundation, where it is dark? Or do you have foam on the outside of the building which could provide termites a place to make a dark tunnel?

6. 
   user-939142 | Oct 05, 2011 03:24am | #6

   i'm in roughly the same zone as you iLL

   building codes may dictate if you have to worry about termites
   the metal strip also provides a drip edge, and possible decoration; there are a number of products like this and also building codes vary on what they will allow

   i'm no expert but generally the edge discourages the termites/ants from 'crawling' around it. foam is not a food source but can provide shelter to either pests, although why they would hang out there when no food is around is a good question. foam products are made that have borates in them that will make both pests unhappy.

   and part of the point of green building would be to eliminate pest services if possible....