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EP 40 · 2023-01-23 · 47:20

Cellulose Insulation in Atlantic Canada: Fire Performance, Retrofit Moisture Risk, and the Net-Zero Shift | Thermocell & Greenfiber

Matthew Brennan of Thermocell/Greenfiber Canada unpacks cellulose insulation—fire performance, retrofit advantages, dense-pack wall systems, and why net-zero building codes are finally making green product specs a selling point rather than a conversation-ender.

The story, written up — a sharp read with every fact on the record. Or skip straight to the moments that matter, as clips.
Read the article ▸▶ Watch the 14 clips ▸Read the transcriptOpen on YouTube ↗
// CHAPTERS — TAP TO JUMP THE PLAYER
0:00Sponsor ReadsPizant Building Products sponsor read; Procore partnership announcement.0:42Welcome and Small TalkHost introduces Matthew Brennan, National Director of Sales for Thermocell and Greenfiber Canada. Light Christmas/World Juniors hockey chat.2:14Matt's Career JourneyMatt traces his path from Toronto NS, Kingston Aluminum, St. Mary's finance/economics degree (2008 cohort), joining Solder/Atis Tree, mentorship from Fellaine Renee Landry and Sean Mitchell, then moving to Thermocell six years ago.6:40Company Background and Cellulose BasicsThermocell history since 1987, connection to Kohler Windows, 15 plants across North America (5 in Canada), manufacturing at Debert NS. Cellulose composition, carbon-negative status, hygroscopic properties, and primary use in attics.9:20Performance: Fire, Density, and SoundproofingComparison of fiberglass vs. cellulose vs. spray foam on density spectrum. The 'big burn' house test showing cellulose held 45 minutes longer. Class 1A fire rating. STC-54 sound performance for between-floor applications.12:00Product Evolution and the Two-Hour Fire WallResidential to commercial/institutional expansion. New two-hour fire wall product for multi-res townhouses (replacing shaftliner); launched in Atlanta, Phoenix, and DC markets; Canada launch being planned.16:10Retrofit Market and Passive House/Net ZeroWhy cellulose suits retrofit: handles moisture unknowns, forgiving in variable assemblies. Thermocell's work with Habitat for Humanity Halifax, the Recover project (bolt-on wall cladding initiative with Nick Ridnicki). Passive house credentials and consultant designation (Matt pursuing). Staff education investment.20:00Installation Methods: Attics vs. Dense-Pack WallsThree installation methods in Canada: loose-fill, dense-pack, and hybrid. Wall settling misconception explained—2-inch drop is designed in. Dense-pack target density 3.5 lbs/cubic foot, tracked by bag count per section. EnviroShield CCMC-approved wall system.26:10Agriculture and Soundproofing Niche MarketsCellulose for agricultural buildings (chicken/potato farms, valley NS and northern NB): borate treatment repels pests naturally, measured productivity improvements reported by farmers. Commercial soundproofing floors and walls.28:40Atlantic Canada Sales LandscapeThermocell's team in Atlantic Canada, Debert plant running 7 days/week, strong sales amid construction boom; competition primarily fiberglass (Owens Corning) and spray foam, with cellulose competition (Suprema, Quebec) only lightly entering the Maritimes.31:10Sanctuary Brand and Consumer ShiftGreen Fiber merger narrative; Sanctuary product launch in US (runner-up sustainable product at Home Depot). Consumer attitudes: 2015 green messaging fell flat, now 83% North American study says consumers prefer environmentally conscious products. Sanctuary home concept—cellulose walls+attic = soundproof, healthy, efficient home. Sanctuary Builder and Sanctuary Trusted Contractor programs.35:00Competition and Industry ConsolidationCellulose manufacturers historically hyper-regional and small; Greenfiber's 15-year consolidation giving cohesive messaging against Owens Corning and other multinationals. Market position as North America's largest cellulose manufacturer locally manufactured in Atlantic Canada.39:00Labour Shortages and ImmigrationPlant running at capacity; irreplaceable long-tenured staff (one from 1987). ABSDA conference on immigration as workforce solution. Ukrainian worker success story from a Grandma Nan Home Hardware. Recognition of homegrown trades talent alongside immigration.42:10Industry Outlook and Wrap-UpACP's role in attracting young people to trades (NSCC, building supply careers). Good jobs, good pay, good people narrative. Closing remarks; Cook Insurance and FCA Surety sponsor reads.
// THE INTRO

Host Daniel Arsenault interviews Matthew Brennan, National Director of Sales for Thermocell and Greenfiber Canada, North America's largest manufacturer of cellulose blown-in insulation with a Debert, NS facility operating since 1987. The conversation covers the full product story: what cellulose is (recycled paper fibres treated with borate), how it compares to fiberglass and spray foam on R-value, density, fire performance (the 'big burn' test), and sound ratings. Matt walks through installation methods—loose-fill attic, dense-pack wall systems, and the emerging EnviroShield CCMC-approved assembly—as well as the retrofit market where cellulose's hygroscopic properties make it forgiving of unknown moisture conditions. He discusses the two-hour fire-wall product now rolling out in US multi-res markets (Atlanta, Phoenix, DC) and the forthcoming Canada launch. The episode also covers the Thermocell/Greenfiber merger narrative, the Sanctuary brand relaunch targeting end consumers around healthy/efficient homes, and two programs—Sanctuary Builder (donated product for show homes) and Sanctuary Trusted Contractor (trained installer network). The back half of the conversation addresses Atlantic Canada's construction boom, Thermocell's Debert plant running seven days a week, labour shortages and immigration as a workforce solution, and the role a media platform like ACP can play in attracting young people into trades. Engagement is minimal (185 YouTube views, 264 audio downloads, 0 comments); the episode functions as an insider education session for contractors and builders already working in the envelope market.

// THE LESSONS
See all 12 lessons ▸
Hard early mentors you didn't like at the time often deliver the most lasting career value—recognize and repay that by becoming one yourself.
you realize that and it's the industry as a whole there's a lot of that and you gotta actively contribute
▶ Clip4:54
Cellulose is the pragmatic retrofit insulation choice because its hygroscopic properties tolerate the moisture unknowns that make spray foam or fiberglass risky in older Maritime housing stock.
the big thing with any retrofit job is the unknown right yeah so new construction we have the luxury
18:51
Dense-pack cellulose wall installation success comes down to tracking bag count per section—3.5 lbs/cubic foot is the target density that prevents settling without on-site equipment.
take a 10 foot sectional wall mark on the wall we should have six bags done and blown at this point
▶ Clip27:08
The two-inch post-install drop in attic cellulose depth is designed in, not a defect—educating crews on this prevents unnecessary job-site disputes.
I put 20 inches in and I have 18 inches I must have lost 10 right and they didn't lose anything
▶ Clip24:20
Spray foam has significant on-site failure modes (substrate temperature, product age, machine calibration) that cellulose, as a plant-manufactured product, inherently avoids.
there's a lot of ways to mess it up when we're talking about spray foam
▶ Clip21:30
For new products requiring code compliance, the entry path must hit architects, building codes, and contractors simultaneously—each alone is insufficient.
it's all three for that one yeah so that's the biggest undertaking right now in terms of involvement
▶ Clip16:29
Marketing green building products changed fundamentally around 2020: what fell on deaf ears in 2015 now actively moves product, driven by consumer-demand surveys showing 83% preference for environmentally conscious options.
a complete sea change right like we would I remember going into meetings even in 2015 and talking about this and people say they just don't care
▶ Clip33:05
Donating product to show homes through a certified builder program is a practical route to getting a new product spec'd and sold to end consumers without needing an architect.
if you are building a show home we'll donate product for that show home to basically have cellulose in your walls and your attic
35:24
In Atlantic Canada's construction market, immigration—particularly from Ukraine—is emerging as a viable and culturally compatible workforce strategy for manufacturers and dealers experiencing skilled-labour shortages.
going to that conference definitely opened our eyes to maybe that as a possibility yeah especially for skilled qualified workers
▶ Clip43:00
Manufacturing-sector construction jobs (plant operators, skilled trades) are undersold career paths that the Atlantic Canada industry needs to actively market to NSCC graduates and young people.
good paying jobs good benefits good people yeah
45:49
Regional cellulose manufacturers historically fragmented their market message; Greenfiber's 15-year consolidation strategy is now allowing a cohesive brand to compete against Owens Corning at scale.
it was hard to have a cohesive message against some of these massive multinationals like Owens Corning
▶ Clip37:33
Cellulose's borate fire-retardant treatment doubles as a natural pest deterrent—a non-obvious product benefit with measurable productivity ROI for agricultural building clients.
animals and pests really don't like it and from an agriculture environment that really matters
▶ Clip40:34
// CLIPS FROM THIS EPISODE
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// FEATURED BUSINESS
Greenfiber

North American manufacturer and marketer of plant-based cellulose blown-in and spray-applied insulatio…

Full dossier · 2 projects ▸
// FACT-CHECKED ✓ web-verified, with sources
✓ VERIFIED
Dense-pack cellulose wall target density is 3.5 lbs/cubic foot.
Industry-standard specification for dense-pack cellulose is consistently cited as 3.5 to 4.5 lb/ft3 across multiple authoritative sources (Building America Solution Center, Building Science Corporation, Fine Homebuilding). The 3.5 lb/ft3 figure is the accepted lower bound for self-supporting, non-se…
SOURCE ▸
// COMPANIES & ORGS ✓ verified
Thermo-Cell Industries Ltd. (operating as Thermocell / Greenfiber Canada)Greenfiber (Applegate Greenfiber Holdings LLC)Matthew BrennanReCover InitiativeEnviro-Shield Dense Pack Wall Application System
// PROJECTS NAMED
Recover (penalization/retrofit pilot project)Enviro-Shield Dense Pack Wall Application System
SOURCE: podscope · public episode data · ge2XqON_1Rk