SIP Panels - house construction

[donwon]

In the spring, we will be building a new house. I am looking at SIP panels for the outside walls. We live in a cold northern climate and it makes good senses from an energy point of view.

My question is, has anyone used these to build a house?  If so any feedback or suggestions on them?  Also any alternative products such as raycore etc. Thanks!

 

[Holmz]

I've looking too. With a timber frame style of construction it makes a lot of sense.

Most heat loss in a 2x4 is through the 2x4s, so even the thermal nano-tech gels become worthwhile in the tape form over the 2x4s.

With a TF you generally have the whole shell as SIP, and the timber skeleton inside.
For 2x4 it would be insightful to know how they get used?? One still needs a structure to put the SIPs onto.

The roof maybe worthwhile with SIPs, and the windows is where a lot of heat escapes.

 

[bertv]

Ana White on YouTube is building a house in Alaska with SIP:=PLLVjGYhU0zQZe7qgsZIRhZTtW1TA8j7mH

 

[Wooden Skye]

I've looking too. With a timber frame style of construction it makes a lot of sense.

Most heat loss in a 2x4 is through the 2x4s, so even the thermal nano-tech gels become worthwhile in the tape form over the 2x4s.

With a TF you generally have the whole shell as SIP, and the timber skeleton inside.
For 2x4 it would be insightful to know how they get used?? One still needs a structure to put the SIPs onto.

The roof maybe worthwhile with SIPs, and the windows is where a lot of heat escapes.

Your bottom and top plate will be traditional framing material, but the sip panels eliminate the traditional wall framing.  Sips will be all the structure you need for the exterior walls.  We looked into doing a 30x30 2 story addition and the sip cost was about $30,000 more than traditional stick built.  If I was building a new house, I would go with sips and icf's for the foundation, especially in a colder climate.

 

[Dane]

I built my last house with SIPs- just myself and one other guy, basically.  We had a sort of barn raising party when we put the panels up and got about 10 people involved.  But after that, just 2 or 3 of us built the rest of the house.  I'd say the big lessons are to be ready for other trades to balk and charge you more for basic services that are not much harder with SIPs but are outside of thier normal workflow, so they upcharge.  Use one of the big manufactures- we went with a smaller shop and has some consistency issues.  Since you are in a cold climate, you need to doe some research and thinking on the roof and panel joints.  There's a good research paper from the Department of Energy Building America program which is also on the Building Science Corporation website.  There can be some issues with moisture drive in cold climates that you need to address.  Overall, though, I would do it again.  Let me know if you have specific questions.

 

[clark_fork]

SIP construction is used frequently here in Montana. often combining it with the features of timber-frame construction. Owners cite extraordinary energy savings and report great satisfaction on all counts.

The essential challenge comes down to the air-tightness of the construction. My caution to pass along is to enlist solid engineering expertise to design the air-handling capability of the dwelling ensuring proper make-up air and air circulation to deal with  interior moisture issues.

I am a real estate appraiser. Construction costs run on an average 10% to 15% greater and little of this surprisingly is recovered upon re-sale despite the obvious energy savings that can be realized. This is slowly changing as "green" construction gains greater acceptance.  My second recommendation is to talk with local real estate professionals and real estate appraisers who have experience with "green" properties and get a sense of both local construction costs as well as re-sale issues.

This company has some great examples of combining  SIP with timber-frame construction
http://www.tamarackconstruction.com/

 

[Dane]

I concur with Clark re: ventilation, however, the OP is in Canada which has had an advanced energy code for years that requires ventilation.  Even our own backwoods national energy code is going to adopt ASHRE 62.2 2010....I installed a separately ducted ERV in my house back in 2007.

 

[60North]

Note:
Like any 'factory sealed unit' ask to see what they insulate/put between their panels. All SIP's panels are not the same, price, quality, performance???

Brian.

 

[duburban]

I agree with a lot of what has been said, BUT...

Double stud wall construction is the way to go with dense pack.

I installed HRV units for a while and retrofit them into SIP houses that were rotting from the inside due to tightness.

The issue for me lay in the OSB. Being laminated to foam, it can only dry to one side. I repaired hundreds of square feet of rotten SIP panel because of AVERAGE to MEDIUM flashing details. Every window around the house leaked enough water in to make OSB punky around each one. Rain screen (.5"+ air gap behind siding) is critical.

Repairing rotten osb is scraping off the old osb in small chunks, letting new nailing strip into the foam, and laminating new ply on.

Double stud wall is conventional framing system but more of it. If you are timber framing and as set on it, you can looking into larson truss strapping which creates large dense pack bays external of the frame.

 

[donwon]

Thanks everyone for all of the great info on SIP panels.  I think it general it is fair to sum up everything as below.

1. SIP panels offer great R value
2. They are very air tight and will require a good HRV system
3. Need to ensure proper flashing around the openings.

I was thinking of using Blueskin house wrap to wrap the entire house after construction prior to window install.  Anyone have thoughts on this as it would address some of the points raised in above posts.

 

[w802h]

I can't comment on the Blueskin housewrap - I still like black felt and have never used SIPs.  That said, it's my understanding that the air barrier and sealing between panels needs to be in the foam core and done well.  A house pressurized can get localized rot in the sheathing as warmer, moister air cools and condenses on exterior layers (if leakage exists).  A high performance house wrap would not be enough to solve this issue.  A vapor impermeable layer like ice and watershield on the outside might even make matters worse.