Edmonton-based construction company, Butterwick Project Ltd., has started the first panelized deep retrofit of a single-family home in North America. Butterwick’s ground-breaking approach uses 3D digital imaging to pre-build wall panels that are then attached to the house’s exterior using a crane.

“About a third of greenhouse gases come from the buildings we use right now. Most of these will still be in use in 2050. To deal with the climate emergency, we need to make our homes net-zero long before that. Panelized deep retrofits are a great solution,” said Peter Amerongen, a director of Retrofit Canada’s board and partner of Butterwick Projects Ltd.

“As far as we know, this project’s the first time anyone has tried the approach on a single-family home in North America, and maybe even the world.”

Logan Gilmour, a software developer from the gaming world, digitally captured the dimensions of this 1,950-square-foot 1940s home using a drone and his custom photogrammetry software.

Peter Amerongen used Logan’s 3D models to design the pre-built panels. Logan and Butterwick’s process, which is inspired by a Netherlands technique called Energiesprong, has three to 5 mm accuracy.

After the airtight panels were built and delivered, Butterwick crews worked with a spider crane operator to install them. All the panels were installed in less than a day and fit beautifully.

For homeowners Jim Sandercock and Melanie Harmsma, the deep retrofit is about reducing their family’s carbon footprint, role modelling climate action for their kids and reducing their energy costs as they prepare for retirement.

Jim, who is also chair of the Northern Alberta Institute of Technology’s Alternative Energy Program, said, “We need to electrify our buildings, but it is not practical when they are drafty with minimal insulation. It would take way too much solar and be a huge draw on the grid in the dead of winter.  I was thinking it would work great if only you just wrap the whole house in a nice warm sleeping bag. Wouldn’t that be better?”

That’s when Jim connected with Butterwick to do the panelized retrofit.

Digital capture on Sandercock’s home was done in 2021. Butterwick began onsite works in May 2022 and installed the panels in mid-June. When the retrofit is complete, Jim and Melanie’s home will use 70 to 80 per cent less energy, making it net-zero ready.

“Net-zero ready” means the building can get all of its remaining energy needs from renewable sources like solar, even in a climate as harsh as Alberta’s.

The project is one of three single-family home deep retrofits Butterwick is doing in 2022. These retrofits are funded in part by Smart Sustainable Resilient Infrastructure Association.

Butterwick Project Ltd. offers integrated construction management services for Net Zero Energy, Passive House, and Deep Retrofit building projects in the Alberta Capital Region. Butterwick serves the multifamily residential, commercial, and institutional building sectors. The company is also constructing the first multi-family home panelized deep retrofit in North America – the Sundance Housing Co-op deep retrofit.

Retrofit Canada is an open-source, deep retrofit organization. We have partnered with Butterwick Construction on Deep Retrofit demonstration projects in Edmonton, Alberta. We want to start a movement to make existing homes net-zero.