Normally I like to hang out in the “Testing Area” forum – lots of great stuff going on over there... But I thought I’d slum it in here for a while.

I’ve learned a lot here about insulating walls.. thanks for that..

While I am in the process of designing an energy efficient ICF home, I have a project at work for which I have a few questions that I thought you all could help me with. So forgive the loads of questions. (I'll have plenty more about the house shortly...)

Part of what we do is dry wood in “kilns” to be processed later. We’re relocating our kilns – actually completely redesigning them and rebuilding them. In a nutshell, the kilns are 20’ x 30’ and about 12’ tall. There will be 6 of these rooms side by side. 4 kilns will share both of their 30’ walls. The outside two kilns will have 1 outside wall each and share their inside walls. Each Kiln will hold about 70 pallets which are stacked two high within the kilns with forklifts. The kilns are located within a 70,000 sqft building with poured concrete floor. I know there will be heat loss through the floor, but we have experience with this. It’s not ideal, but not horrible, as you might imagine, water does condense on the floor.

The nature of a wood kiln (dehumidification style) is that it sees temperatures to about 140 degrees F, and RH from 20% all the way to 90%. Through heating and dehumidification, we control the wet bulb and dry bulb temperatures in order to control the rate at which we’re pulling moisture from the wood (EMC). A kiln cycle is about 2 weeks, and a pre dry cycle is also about 2 weeks. Pre drying is open to ambient air and is merely circulating air through the wood to bring the Moisture Content to as low as 30%. After we pre-dry we start the kiln cycle. At the end of the Kiln Schedule we equalize and condition. There are fans and baffles continually recirculating air and reversing flow regularly.

The goal of this design is to improve over our current construction which is Block walls, and 1” pink stuff with Plywood – they are the same 20’x30’x12’. We would like to have more control over the environment. We don’t want to break the bank though. If we can get above an R25 or so we should see a significant improvement.

The wall design we’ve chosen for the shared walls is 2x6 construction. The stack up is:

½” PT Plywood -- 1” EPS -- Roxul Batt (to fill 2x6) -- 1” EPS -- ½” PT Plywood.

All seams will be taped in the EPS. The PT Ply would be painted with “kool seal” aluminum paint. The plywood protects the walls from damage loading with the forklifts and provides some insulation. The “sill” board on the bottom of the 2x6 wall will be PT lumber and insulated from the floor.

Here are my questions:

What do you think of this wall stack-up given the environment?   Any ideas?

What is a good tape to seal the EPS seams?

What is a good sill board insulation?

Should we tape the seams on the Plywood too?

I’m pretty sure that moisture will penetrate these walls, does this design allow them to dry out? (Keep in mind that after each kiln cycle is a 2 week pre dry cycle with fans circulating ambient air.)

Would it be better to completely moisture seal the walls given the rough environment? (forklifts and pallets)

How would I attach the EPS to the studs?

How would I attach the Plywood through the EPS to the studs?

Should we use PT 2x6 for wall studs?

Thanks a lot everyone for any input.  I greatly appreciate it.  Sorry for all the questions.. 

-C2