Skip to main content

Are you sitting on the dock dreaming about moving up to the cottage permanently? Before you jump in, wake up.

Converting a cottage is a major renovation - one you need to plan carefully, and budget for. Without even having seen your place, I can guarantee you there is more work in converting than you think and it will cost a lot more than you expect.


You'll need to worry about heat. Most summer cottages have only electric heat, which can be expensive, especially if it's your only heat source. Is there a woodstove that you could use to offset your heating costs?

Do you have a furnace already on site? Probably not, but you might want to consider one. Heat-loss calculations have to be made. If you are installing forced air, the ductwork and furnace has to be sized and properly installed by a licensed contractor.


The load on the electrical system increases many times over when a summer cottage turns into a year round residence. A 60 amp service just won't do, which means increasing your service to 100 or 200 amp - that's expensive, and requires licensed electricians.


Summer-only cottages have little or no insulation. Moisture never forms inside the walls because the temperature gradient between the outside and the inside of the cottage is never more than a few degrees. Even if it is and moisture forms, the cottage has enough air movement to vent the walls and attic and keep them dry.

When you add insulation and heat the cottage in winter, the difference in temperature between outside and inside rises dramatically, and now you have to deal with condensation. Vapour barrier becomes essential because it separates the warm moist air inside from the cold, dense air outside and stops condensation inside the walls, which leads to mould and rot.

Any contractor can blow in additional insulation into your wall, or lay down batts in your attic. But that won't do anything to deal with moisture penetration and mould prevention because vapour barrier is impossible to install properly without tearing out your existing drywall.


Windows in a summer-only cottage don't need a tight seal around the framing, or need to be weather proof between the sashes. There is never a condensation problem that causes the panes to frost or a rot problem when the frost melts and settles in the corners of the sill. But all of this will happen with summer windows that are forced to do winter duty.

You'll need to replace and upgrade all your existing windows and doors.


Is your water supply adequate? Will you need a new well? Is your septic system adequate for winter use? If it was originally designed for seasonal/ part-time use, you may have to have it pumped out more often.

If your renovation includes new appliances like a dishwasher, garbage disposal or a large spa bath, you need to make sure your septic tank and leaching bed are designed to accommodate the increased water and organic load.

You will probably find that you need a larger septic system. Not only will this be a major expense, you'll find there are restrictions on where your septic system can be located with respect to nearby bodies of water, wells and your neighbours.

When there is no worry of freezing, the plumbing can be run any way it's convenient and cheap. As long as the pipes are drained before you close the cottage in the fall, they are never in danger of bursting.

But when you are planning on staying over the winter, you need to make sure your plumbing is protected. It must be run on the warm side of your insulation, or your pipes will freeze and burst. If they aren't, the pipes have to be rerun. In my experience, the plumbing of a summer-only house always needs to be completely redone.

Converting a seasonal cottage to a year-round home is tricky to get right and needs the most experienced contractor you can find. It is not a quick fix.

Mike Holmes is the host of Holmes on Homes on HGTV.