I live in Southern Illinois and my wife and I had a baby girl in October, we have been living in a 16 x 80 home on 5 acres. Now that we have this little girl the home is getting smaller every day. I am 3 years into owning a small hardware store and starting to farm with my Dad so my budget isn't what I would like but I suppose its time to build that home regardless. Our plan is to build after we harvest this fall and into Spring of 2015. I've been working out details with a builder who specializes in pole barns. I'm planning to build a 64 x 48 stick built home with 2x6 walls with metal on it to appear as a pole barn. I sale metal through my store so its my cheapest way to go. My builder wants to deck it with OSB and then wrap it in Tyvek. I am putting it on a slab and I have told him I want to put at least 2" of XPS under the slab and along the sides. He had never heard of it but after researching online that seems like something that will greatly help without a lot of expense. As of right now and I am thinking to have dense packed cellulose in the walls and spray in loose fill at R49 in the attic. I love the way the closed cell has such a high R value and that it strengthens your walls but I simply don't know if I can afford it and worry about off gassing with my little girl as well. I have an estimate to do it all for $5810 installed. I'm guessing that the closed cell would be close to 3X that amount. Also one insulation contractor that uses both loose and closed cell insulation said he worried that with a slab and metal exterior that I may have a big problem with moisture coming up though my floor if I seal off everything with closed cell foam. Is that true? I'm looking for different ideas that would be cost effective to help me make this home energy efficient and safe for my family. I have toyed with putting XPS on the OSB and then wrapped but my contractor and my Dad both think I need to stay off the internet. When I told them about thermal bridging and that a 2x6 had an R value of 7 they acted like I was from another planet. LOL I heating and air guy has me talked into a Coleman Echelon Series heat pump with R9 insulated duct work. Will I still need to put some type of insulation in the rafters or will the loose fill cellulose covering it be sufficient? My ceilings will be 9ft by the way. Do any of you believe in the ZIP or SIS Structural Thermal Sheaving? Would something like the new Tyvek R5.0 be worth my time to use rather than just Tyvek? Any and all ideas are appreciated because I am way out of my element with this but I want to make educated decisions for my families future home without breaking the bank. Thanks in advance and I apologize if I rambles on a bit.

Good plan overall! the cellulose in the attic will be fine as long as you seal all the penetrations and avoid recessed lights; you do not need spray foam. do not put any ductwork in the attic - insulated or not; so you may need to build duct chases under the ceiling if you go with a ducted system.
Using EPS foam on the exterior of the osb will still allow water vapor to pass through the wall while providing a thermal break. Outside the foam, strap the wall with 1x3s or 1x4s (rough or smooth; doesn't matter) then fasten your metal siding to that. The strapping provides a "rainscreen" and also disconnects the wall from the siding so the wall will still be able to pass moisture before the moisture reaches and condenses on the metal siding.
Consider using EPS foam under the slab - cheaper than EPS and better for the environment. Install a layer of 6 mil poly above the foam and just below the concrete & tape the seams. this will keep the moisture that is in the ground under the house from passing through the concrete and help reduce the moistiure levels in the house.

Amazing to me that automobile technology is finally advancing in leaps and bounds, but house construction technology is stuck in 1978. Ask the naysayers if they'd buy a new 1978 Chevy today rather than a 2014 model?

There are details in all of these things which you can learn here or/and at http://www.greenbuildingadvisor.com/ but your overall plan is a good one.

correction:
Consider using EPS foam under the slab - cheaper than XPS and better for the environment.

I would ask insulation contractor for the price difference in the attic between R49 and R60. Once he is out there, the cost of the added material is very minor. The 2014 codes (they may not yet be adopted in your locale) do require some level of outside insulation. How much varies based on your weather zone. Check with ZIP system supplier to be sure you can fasten metal siding to it, even if you use the strapping.

Thank you Bob, I appreciate your input. I haven't heard much about the EPS foam. I will check locally and see what I can find. I am trying to do my researching now so that I have plenty of time to try to accumulate product at sale prices through whatever means I can find. You mentioned " if you go with a ducted system" . What other options are there to a duct system? I'm still checking prices on a crawl space but I am afraid the expense might be too great and also I don't want steps into our home as I am planning on living here til a ripe old age, 36" interior doors, shower without a threshold etc. Do you get the EPS board at the same type box stores as the XPS? R-Values similar?

Thank you so much.

Thank you as well McFish, I was already thinking about having him spray a little extra cellulose while he is up there. Most folks here in my area think you either have to go ICF or Spray Foam to get a tight home. I just really can't afford either so I truly appreciate the input from you folks that have the knowledge to help me get the safe energy efficient home for my family. Thanks again.

Isn't that area part of tornado alley?

Yes it is, why? I'm putting an above ground shelter in the master closet of our bedroom. A 4 X 6 will run me about $3800. Is there another concern about my construction?

IMO...If I lived in tornado alley I wouldn't have anything but a concrete house. You can even have a concrete roof. I would also think that insurance com. would charge less for an ICF house. For the walls, you could be a DIY with good sup. from the mfg.

I thought very serious about an ICF but we just can't afford one. Our answer for it was to build a cheaper type home and put in a safe room. I might check into it again, its been a while since I tried to price one. It would not bother me a bit to live in a walk out basement, I actually like the idea.

r u looking for a new home




Sydney kitchens | custom kitchens

We are looking to build one this fall after our harvest.

Posted By Bob I on 23 Feb 2014 09:11 AM
correction:
Consider using EPS foam under the slab - cheaper than XPS and better for the environment.

Great if you can find it. CreteHeat uses EPS in their all-in-one system.

Posted By McFish on 23 Feb 2014 11:30 AM
I would ask insulation contractor for the price difference in the attic between R49 and R60. Once he is out there, the cost of the added material is very minor.

As is the ROI for over-insulating in your climate.

We help people with mechanical systems for existing, unfinished pole barns and new steel buildings. We often use FPSF standards to finish off such buildings. The one we are on now will have a 1/2" of Thermax nest to the outside metal, glass and drywall. The vapor barrier is to the outside allowing air moment from foundation to ridge vent.

I would consider a steel building like the one we did in Alaska in 2006. The owner lives in two stories on one end and has his shop and loft on the other. Foamed hot roof and side walls for all with framing and more insulation in the living area.

There is nothing as efficient and comfortable as slab-on-ground construction but high wind is as good a reason as any to have a proper cellar.

Thank you all, its a lot of responsibility with a young baby to build a home that is both energy efficient and safe. I appreciate every bit of knowledge from you all.