So....maybe you’ve got a design already or you are thinking that it's time to design a custom home for you and your family.
What’s the best method to construct it?
We are fortunate in Canada that there are numerous technologies available to us.
- Site-built wood frame construction (This is the time-tested typical method in Canada and elsewhere)
- Insulated Concrete Forms (ICF)
- Concrete Blocks. Not often used as the walls require the addition of considerable insulation to be effective in Canada, which usually results in the addition of wood frame walls.
- Structural Insulated Panels (SIPs)
- Light Gauge steel frame (similar method to wood frame using cold-rolled steel components).
- Factory-built Panels, assembled on site (Panelization)
There are other very uncommon methods; Log construction, Straw Bale construction, and Rammed Earth walls. These methods are used rarely and usually to correspond to the needs of sites that are remote or offer the correct material on-site and the interests of extreme D-I-Y-ers.
My experience has been most clients don't spend much time thinking about what construction method to use, opting for the typical site-built wood frame method. As this method is so common and known, it is simple to find builders and compare quotes. It’s also simple to understand the process / timelines and therefore have reasonable expectations and understanding regarding the schedule, cost and outcomes.
All the methods have pros and cons but the one method I feel should enjoy more popularity is panelization so that is what I’ll discuss here.
Why does Panelization compare favourably to site built?
- Despite the panels being assembled in a factory, the construction is still wood-frame so complying to municipal and provincial building codes are not a barrier and building officials are not confused, leading to little or no regulatory headaches.
- Controlled build environment leads to faster wall construction and quality not compromised by rain, wind or other site conditions.
- Optimum material use, less waste.
- Faster on-site assembly, quicker close-in, less safety and theft risk on-site.
- More ability to construct year-round, shorter construction time, often reduced financing costs.
- Ability to change walls due to unforeseen site conditions or client decisions reduced. Changes after factory fabrication is possible as these are, in the end, just wood studs and sheathing, but when site-building there is the added ability of adjusting while you build versus after you build.
Cost aspects are arguable and dependent on project specifics. Generally though, factory labour is less expensive than the on-site labour it replaces and the decreased material, time and site management cost (waste removal, theft risk) should lead to decreased overall project costs.
Depending on the factory chosen to build the panels for your home, it's also possible to to have studs predrilled for electrical cabling and wall chases pre-constructed for HVAC needs. This saves labour for the mechanical sub-trades and can improve quality as well. Some factories can even pre-install mechanicals, further reducing labour costs.
Some study’s show 15%+ of cost reductions.
General and cost information.
Is there a reduction in design flexibility?
The short answer is no.
Panelization factories convert your Permit draftings (stamped by a BCIN designer or Architect to ensure it meets local municipal zoning regulations and building codes) to individual wall panels. So you start with a building site and blank sheet of paper, same as other construction methods. Having said that, many factories offer stock plans so if you go that route, your design flexibility is more limited.
Reduced time, improved quality, cost equal or less than traditional construction. It seems like a method waiting to take off!
In the Ottawa area there are numerous factories that can provide this service. An internet search will reveal options. As always, its worthwhile to discuss with your designer these options as part of the design process in order to take full advantage.