Installing LP Smartside over 3″ foam
Question: I am putting an addition on my house and have a question about fastening the LP Smartside.
My wall details are as follows (from inside to outside).
* 5/8″ sheetrock
* 3/4″ plywood
* 2×6 wall with r-19 or 21 fiberglass insulation
* 3″ foam
* Furring strips, probably 2×4 – has to be at least 1 1/2 thick per LP
* LP Smartside
My question is, what is the best way to go about preventing the siding from sagging (over time) when installing. With a 3″ space between the furring strip and 2×6 stud wall (styrofoam), there is a lot of unsupported weight there. Worried that with all of the weight, over time, the screws will eventually bend down/sag.
I am getting some different opinions on the best route to go……some of them are:
* Move the wall assembly in a little ways onto the floor so the bottom of the furring strip will be supported on the floor (subfloor/rim joist area).
* Move the whole rim joist/floor detail in a ways on the foundation (poured 8″ thick x 5′ deep) and then run the furring strip down to be supported on the foundation itself.
* Install the system in the normal fashion (if there is one!) and not support the bottom of the furring strip. Instead, use large lag bolts every so often on the furring strips to help support the weight, or even run the furring strips up higher and secure to the rafters for additional support……kind of a hanging system
To add to the mess, it sounds like i will have to have 2″ or 3″ of foam on the exterior of my poured foundation walls!! I want to avoid having the foundation foam being proud of my whole wall/siding detail.
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