
Cutting the uncertainty in retrofit costs
Jan. 28, 2025
The cost of a community-scale home energy retrofit program can be estimated more realistically, thanks to a recent workshop held in northwest BC with the Community Energy Association, Nisga’a Nation’s Housing Committee and Natural Resources Canada.
Accurate costing is very important for enabling community-scale home energy retrofit initiatives—one of CEA’s top priorities. CEA first helped support a community-scale home energy retrofit program in ʔakisq̓nuk First Nation and Retrofit Assist is now enabling hundreds of home energy retrofits in five BC communities.
But, in all of these efforts, CEA’s Gaëtane Carignan says we always face the same stumbling block. “People say deep energy retrofits make all kinds of sense… but how much is it going to cost?”
There’s no easy answer. Project costs vary regionally due to differences in product availability, labour costs, the length of the construction season, even things like availability of accommodations for workers.
That’s why, in December 2024, Carignan and the Nisga’a Housing Committee brought together a “who’s who” of northwest BC’s building industry to really nail the costs down. Using a methodology from Natural Resources Canada, the costing workshop (or charette) they organized generated a wealth of accurate estimates verified for the Nisga’a and Terrace region.
“We now have the best data available for northwest BC,” said Carignan. “It’s a pretty exciting opportunity!”

Getting to the next level
To understand how the costing workshop came together, we should start earlier in 2024, at the Northwest Energy Retrofit Forum. This three-day event was an indepth exploration of deep energy retrofits, with training on integrated design processes, workflow strategies, management considerations, and building science best practices.
Importantly, it also produced strong relationships. The site visits in the Nisga’a village of Lax̱g̱altsʼap, especially, gave local contractors and Nisga’a housing committee members the time and space they needed to connect and build a shared understanding of retrofit needs in the Northwest.

So when the opportunity arose to organize the December 2024 costing workshop, Carignan included another site visit. On Dec. 10, she drove three hours to the coastal village of Gingolx—a small Nisga'a community so remote that it was only accessible by boat and air until the early 2000s.
Joining her were the workshop facilitators from BCIT and Natural Resources Canada, an energy advisor, a Terrace building official and members of the Nisga'a Housing Committee. They were able to look at some houses, speak with tenants, do thermal imaging, and discussed how the homes were constructed.
“It was important to orient people to what we’re requiring,” said Carignan. “These aren't just any old retrofits—these are energy retrofits that are going to create healthier homes, more durable and climate resilient homes.”

This time spent together in community set them up for success the next day, during the costing workshop back in Terrace. It took place in a rustic meeting room at Hidden Acres Farm, a space packed with plaid shirts, puffy vests, hoodies, and ballcaps—contractors, builders, suppliers, energy advisors, the Nisga’a and Terrace building officials and housing managers, and building science instructors from BCIT.
It was a large and diverse group, including many key players in northwest BC’s construction industry. That they had been pulled together in just a few weeks is a real testament to the bonds that had endured since June’s workshops.
“It felt really special, this collaborative feeling and that there were trusted relationships in the room,” said Carignan.
Developing verified cost estimates
Participants were invited to share their experience on scheduling, logistics, material and labour costs. Guided by Lucas Coletta, an Ottawa-based construction costing expert for Natural Resources Canada, the group collaboratively developed a deep understanding of the costs associated with energy retrofitting homes, using building science best practices, in remote communities of northwest BC.
“Lucas is a specialist in this work and he’s really good. He only does five of these yearly nationwide, and this was the first directly in service to the aspirations of a First Nation,” said Carignan.
The group started with estimates drawn up by Oriol Bracken, who brought her background as a construction project manager to CEA, with input from Ben Coultish of Terrace’s Cedar Ridge Builders. Following Coletta’s methodology, the group re-examined everything that could go into a home retrofit: every component of the envelope, mechanical systems, the demolition process, waste management, labour, accommodations, travel. By the end of the day, they had a price for everything identified, debated, and verified.
“Oriol and Ben laid the foundation, but now our numbers were verified by multiple competitors and by a diversity of stakeholders,” said Carignan. “It wasn't just general contractors in the room, it was also suppliers, a transport company, a mechanical systems technician, and energy advisors.”

Verified costs enable realistic support programs
Having verified cost estimates for this specific region in northwestern BC really does make a difference. Now, if Nisga’a Lisims Government and the Nisga’a Housing Committee run a community-scale home retrofit program, they have a very good understanding of how to do a cost-benefit exercise on each house. They’ll understand if it may be better to tear down and start over. And they’ll know the trade-offs of prioritizing windows or insulation, roofs or heat pumps.
“We came out with a better understanding of the building science and what's going to be required, and then also how we're going to write our request for proposals, and what sort of spin-off economic development opportunities they can seize,” said Carignan.
Housing is one of the biggest opportunities for local governments to tackle climate change and improve residents’ lives at the same time. Up to 30% of Canada’s greenhouse gas emissions are tied to buildings. Home energy retrofits can cut into that carbon pollution while also giving residents healthier, more comfortable and affordable homes.
Thanks to CEA’s long-term efforts to bring together northwest BC’s building community and stakeholders, Nisga’a Nation is one step closer to achieving their ambitions on housing retrofits.
“James Percival is the building official for Nisga’a Lisims Government. He came over to me, shook my hand and looked me in the eye. He said, ‘this has never happened before.’ He was just so pleased with this coalescing of regional players coming together to get behind the Nisga’a retrofit project.”
If you would like to work with the Community Energy Association on retrofit costing in your region, let's get in touch!
Please email gcarignan@communityenergy.ca or obracken@communityenergy.ca with your inquiry.
The Retrofit Costing Charette in Terrace, BC, was the latest of many capacity-building activities organized through Building A Legacy North, a collaboration of the Community Energy Association and the Canadian Home Builders Association of Northern BC.
Building a Legacy North builds capacity in high-performance construction in both new buildings and retrofits.
The costing workshop was supported by the Nisga’a Lisims Government, the City of Terrace, and Natural Resources Canada, with core funding support from BC Hydro.