Hi everyone! I've spent the last couple of days browsing through this forum and learning as much as possible about SIPs and ICF construction as my new home (first time home purchaser 1.5 months ago in Livingston, Montana) is a combination of the two styles. Thank you so much for all the information.
Before purchase, inspections went well and inspector was generally impressed with the construction quality and insulation characteristics of home. Living in the home for a month with radiant heat has been extremely comfortable as winter has arrived.
However, not all news is so great...
I'm currently overwhelmed having discovered a non-trivial SIP panel issue, and seeking any advice from experts who can guide me towards ideal solution.
The home is 25 years old, and has a handful of layout oddities but in general we really love it and have been fixing it up to suit our needs.
While removing the basement carpet and baseboards in preparation of replacing with new flooring, I discovered a spot behind one the baseboards where cold air was blowing into the home.
After further investigation, tearing out part of the back deck (that looked in good shape from above - pic 1) exposed the completely rotted bottom half of exterior 2x12 wood base panelling (pic 2). Pulling off these rotted I discovered (pic 3) a completely rotted out lower foot of OSB on the sip panel, plus a network of mice tunnels through the EPS Foam, leading directly to the interior corner of the house where I felt the cool air - mystery solved...now to figure out how to fix it??
Pic 1:
Pic 2: (Only seems to let me post one pic per page so will post in reply)
Pic 3: (Only seems to let me post one pic per page so will post in reply)
I'm assuming the rot occurred hidden out of sight for years due to snow buildup and melt in that inner corner, and lack of proper drainage underneath the deck. The mice making it their passage way into the walls didn't help things.
Of course part of solution is having some mice pros come out to determine extent of current mice infestation and resolve, which sucks, but I've experienced this before and can handle it.
My bigger concern is the structural integrity of the sip and bottom sill plate and how to properly remediate/repair?
The base (sill) wood (2x6 I think) under the OSB is also largely rotted from the outside - I've scraped out at least 1-2 inches inward from outside before hitting solid wood. Also rotted as are the lower parts of the adjacent vertical wood beams to the right (outer corner end) of the damaged OSB.
Both the neighboring SIP panels are in better shape. The outer corner panel just has a tiny bit of rot maybe 4 square inches in its lower left corner. The inner corner panel (also hidden behind part of the deck in above pic) has rot on the lower external OSB ranging from 1-10 inches high, but underlying EPS is fine. It is also still slightly rotted on its sill plate but not as bad as the one with the mice holes.
The inner corner interior SIP connection appears to be fully secured via spray foam adhesive from the inside, with just the mouse portal coming in through the EPS on the bad SIP panel. I've attached a 4th pic in the replies to show the inside connection as best I can.
So yea what started as a flooring replacement project has quickly turned beyond my paygrade. The handyman I work with who is more than capable of patching it up (steel wool and spray foam in the mice tunnels, cut out OSB rot and re-adhesive replacement OSB in it's place, weather wrap, replace siding). But he recommended I consult with some experts before just putting a bandaid on it...especially due to concern of structural integrity due to missing foam and rotted OSB / sill plate.
I'm trying to reach out to local contractors but everyone is swamped and not sure any of them even have SIP expertise. Spoke on phone to an employee at the local manufacturer of SIP Panels in Belgrade, MT (https://bigskyrcontrol.com/), and he was helpful with outlining remediation tips in previous paragraph, but he was not a structural engineer and couldn't provide advice on possible load bearing issues. I watched a ton of videos on removing rot from sill boards in regular construction, which seems like quite a beast on it's own, jacking up the house and everything, but don't even know if that's possible with SIPs? Any advice on who I might try and reach out to to ensure we handle this properly would be greatly appreciated. Thank you so much.
-Trevor