A cottage built for July is a different animal in January. Thin walls, a floor open to the crawlspace, single-pane windows somebody’s uncle installed, and plumbing that was meant to be drained every Thanksgiving.
We build on Georgian Bay and have seen a lot of these. Some convert beautifully. Some cost more to fix than a new build. The heat loss is how you find out which one you have before you spend the money.
Start with three phone calls before you start buying anything.
The building department. Ask what permits your conversion needs and what they want to see. Insulation, heating, plumbing changes and additions usually need a permit, and some townships want to review a change from seasonal to full-time use on its own. If you are still deciding, see year-round vs seasonal cottage builds.
The road. Is it maintained year-round? Some cottage roads are not plowed. Your township can tell you, and it matters for emergency access as much as for getting to work.
The septic. A system sized for summer weekends may be too small for full-time living. Our sister site can run a free septic check so you know where you stand.
We have seen owners insulate, drywall and install a heat pump, then find out the road or the septic stops the whole thing. Make the calls first. They are free.
A year-round conversion usually needs mechanical ventilation shown on the ventilation summary (RMVDS) with the permit.
Walls, ceiling, and especially the floor. A cottage on posts or over a vented crawlspace loses a huge share of its heat through the floor.
Sized from a heat loss, not from the old baseboard count. A cold-climate heat pump, propane, or a mix, with backup for the coldest nights.
Pipes moved out of the crawlspace or protected properly, and a plan for the water line and the well. One frozen pipe in February pays for a lot of insulation.
A tight, insulated cottage needs mechanical ventilation, usually an HRV. Without it you trade cold for condensation and mould.
Working smoke and carbon monoxide alarms, especially with any fuel-burning heat or a wood stove.
Not always new windows. But single glazing and gaps you can see daylight through will dominate the heat loss.
Room by room, wall by wall. You see whether the floor, the windows or the roof is your biggest loss, and spend there first.
Run it on the cottage as-is and again with planned upgrades. The difference tells you what the insulation buys you in equipment size and in fuel.
A heat pump that is too small leaves you cold. Too big costs more and short-cycles. The number decides.
Most building departments want a CSA F280 when you add a heating system. Ours is BCIN-stamped and ready to submit.
Design temperatures along Georgian Bay and into Muskoka run from about -24 C on Georgian Bay to -26 C in Muskoka, compared to about -18 C in Toronto. That gap changes the size of everything.
A heat pump that is fine in the city may need real backup at the cottage. We use the design temperature for your exact location, not a guess. See Georgian Bay heat loss and Muskoka heat loss for local detail.
And many cottages are off the gas line. We design around propane, heat pumps, electric and wood, whatever you actually have. See propane heating design.
Converting this year? Get the heat loss first. It tells you what to fix and what to buy.
Get Free Quote →Usually yes. Adding a heating system, insulating, changing plumbing or adding rooms all tend to need a permit. Some townships also treat moving from seasonal to full-time use as something they want to review. Call your building department before you start.
Maybe not. A system sized for summer weekends can be too small for a family living there all year. The daily design flow depends on bedrooms and fixtures, and the township may want it checked. Our sister site can run a free septic check.
A real heat source sized from a heat loss, insulation it probably does not have yet, plumbing protected from freezing, mechanical ventilation, and working smoke and CO alarms. Plus a road the plow comes down.
Often, once the envelope is fixed. A cold-climate heat pump with a backup source works in a lot of Georgian Bay and Muskoka conversions. The heat loss tells you whether the heat pump can carry it or the envelope needs work first.
As backup and for comfort, it is great. As the only heat in a full-time house, many insurers and townships will want a permanent automatic heat source too. Wood stoves also need their own permit and proper clearances.
Our CSA F280 reports start at $395. For an older cottage we work from your sketch and what you know about the walls, floor and roof, and we say clearly where we had to make an assumption.
Send us a sketch of the cottage with room sizes, what you know about the walls, floor and roof, and where it is. We calculate the heat loss as-is and with your planned upgrades.