Looking for a “green” modular builder willing to ship to NW Canada
We are building a duplex that will not use any fossil fuels up here in Yellowknife, Canada. (18 hours north of Edmonton – Climate zone 8 – same as Fairbanks). Our lot is on 100% granite so no basement, no slab on grade – we’re building a “box on legs”. We aim to invest as much as we can in insulation and then heat with wood pellets & some of our local hydro electricity ($0.30/kWh)
We also want green materials which are hard to find here & our trades are very expensive so many people are going with prefabricated modules.
Problem is that the insulation levels we want are even higher than what would count as a passiv haus in “the South”.
Here is what we are thinking – we want to start with a southern modular home built with green materials. In my mind that means no spray foam and probably not even foam board. Low VOC, low formaldehyde, & careful on the flame retardants.
We’ll bring it up here with no siding & then air seal it on the outside of the plywood or OSB with roofing membrane or something similarly sturdy. Then insulated (exulate) on-site with a thick layer of Roxul & apply siding. At least the walls, but perhaps floor & ceiling too if we can’t get the R values we need at the factory.
Advantages: can bring up slightly wider modules, can do air seal & blower door test before insulation is added, no shifting of insulation during trucking
Has anyone tried this before? Any factories that might be worth asking?
Andrew
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Replies
Have you considered a panelized approach by using Cross Laminated Timber? (The Belgium's used CLT for a science station in Antarctica!) The advantages are: Thermal mass, ultra-airtight, carbon sequestering, sustainable material, and very quick to assemble, just to name a few...reach me at [email protected] if you would like more info. We can ship out of Whitefish Montana.
i would avoid the use of CLT, just from a cost standpoint. while i'm a huge fan, i just haven't seen the numbers work for single family housing (yet, anyway). as a substitute for concrete in low-mid-rise, heck yeah.
there were a number of prefab panelization outfits at CanPHI's international passive house north conference.
of note was a project done by tom gyimesi, building and trucking a project to edson alberta, in snow. impressive install. info here: http://5thc.ca/projects.html
Pacific Homes ships panelized homes all over including Alaska and the Canadian north. We used them for our house in southern BC with R 43 walls and R 60 ceiling. You don't have to use their special Smartwall system with foamboard. We did staggered stud walls with cellulose or you could do double walls or I-joists. We also used the roxul on exterior (see http://www.agreenhearth.com) .They send the whole house package and the shipping would be more reasonable than a modular I think.
For modular there is:
https://www.youtube.com/watch?v=4ggSuZox_RU&list=UUaPKG9a2t_2XfM8GL4IsHIQ&index=1
https://www.youtube.com/watch?v=oz5DP-oCEpY
or some regular modular builders like Freeport which you may be able to customize and augment
Thanks for the replies.
I saw a fantastic Passiv Haus in Tromso, Norway that used CLT & Rock-wool.
http://www.architizer.com/projects/i-box-120-and-storelva-northern-passive-houses/
Panel systems are a possibility, but that still leaves us with a lot of finishing work. As far as I understand our local market, this is what is so costly her in northern Canada - electrical, plumbing, finishing. That is why I was interested in modular - get as much as possible done with cheaper southern labour!