Family-owned and proudly serving Northern Ontario since 1950.
We're not a box store — we're the local team that knows your project, your timeline, and your name. Our 10,000 sq. ft. store, covered warehouse, and full-service lumberyard mean you get everything in one trip.
As Castle Building Centres members since 1974, we deliver competitive pricing backed by a national network — while remaining independently owned and community-driven.
Framing lumber, plywood, decking, fencing, roofing, drywall, insulation, hardware and more — stocked in our covered warehouse and outdoor yard.
Our 15-member bilingual team brings hands-on construction experience and building code knowledge to every single customer interaction.
Active members of the Northern Corridor Chamber of Commerce, CFIB, LBMAO, and the Canadian Retail Hardware Association. This is our home, too.
“Planned my entire garage build through Knowles. They did the take-off from my blueprints, delivered every stick of lumber on schedule, and the price beat the big box stores in Timmins. Couldn't ask for more.”
“20 years running crews in Northern Ontario. Knowles is the only supplier that consistently gets my orders right the first time. Their take-off service alone saves me hours every week. That reliability is why I keep coming back.”
“First time staining a cedar deck and I had no idea where to start. The team spent 20 minutes with me picking the right product and walking through application. Turned out perfect. Love supporting local.”
Proudly serving Kapuskasing, Smooth Rock Falls, Hearst, Moonbeam, Fauquier, and surrounding communities across Northern Ontario.
Visit us in Kapuskasing or Smooth Rock Falls, give us a call, or request a quote online. We're here to help — and we always have been.