Imber Akse House – Burlington’s LEED home

As part of being enrolled in the LEED Home Canada Pilot, our builder and perhaps us, home owners, will be asked to comment on the sustainable build process as well as the practicality of LEED in Canada. In general, most of the comments are straight forward but there is one big thing which I believe the industry has overlooked, or, overlooks on purpose.

The issue is that when building a sustainable home, rather than conventional, the sustainable model is upside down in the order and cost of the build process. Really, it is. I don’t mean that you put the roof on before the walls but I do mean that all materials and systems have been stepped up in quality and complexity, require more attention and a particular order of completion that is somewhat different than typical.

Take heating for example – and I’m over simplifying for sake of argument. In a typical house the order is the foundation followed followed by walls, sub floors, roof deck, electrical, insulation, roof shingles, drywall starts, venting and ducts, drywall finishing and painting, flooring and lastly don’t forget to pick up a furnace on your way home honey. Done.

Now take a sustainable home – like in our case a high performance one. The first thing is to plan the heating, followed by foundation, followed by heating dig/drill, followed by walls and sub floors, finished roof system (no temporary), install heating GSHP units and HRVs, ducts, electrical, insulation, radiant floor system embedded in concrete finished floor, drywall and finishing and paint.

Subtle difference I know and in some cases this can be adjusted but the big thing is it’s different and the weight of the costs are in those few items that got loaded up front. So big deal – what’s the problem. Well the problem is:

1. Trades are used to the traditional order of things so a floor that goes in early get’s damaged – so you have to cover the floor with costly plywood coverings – wasteful too

2. Banks are used to the traditional order for their financing draws on a point system so a cost weighted toward the beginning leaves everyone scrambling to pay for the heavy upfront outlay before the bank catches up on the paperwork

3. Many systems are attached to each other determining installation order, or require trades working in isolation without overlap in the home so adjusting the order is complex or impossible – ie. insulation is a vapour until expanded so nobody but the installer is in the house – means more time, or radiant floor that will be embedded in cement requires testing during install to the subfloor and prior to concrete pour therefore the whole Geothermal (GSHP) system must be operational – not thrown down there at the last minute after the house is done when you find one on sale

In the end the outcome is a highly efficient home that looks like all the rest – it’s in the order of build and restrictions of install that can cost more due to timing and damage from trades not used to working with the new sequence.

This entry was posted on Friday, December 12th, 2008 at 12:32 am and is filed under LEED, New Thinking, Sustainability, Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.