Can I add a bump-out to my bathroom for a walk-in shower in Ottawa?

Adding a bump-out to make room for a walk-in shower is one of the more practical small additions you can make. Many older homes have bathrooms that are too tight for a modern walk-in shower, and a modest bump-out along an exterior wall can make the difference without the cost of a full addition.

Start with the shower size you want. A walk-in shower needs a clear footprint plus room to step in and dry off, and roomier layouts need more length along the wall. Lay out the shower, door swing and fixtures on paper first. That tells you how much depth the bump-out has to add, and whether it can be a cantilever or needs piers or a foundation. A structural engineer or designer will confirm what your framing can carry.

As broad perspective rather than a quote, a bathroom bump-out with a walk-in shower can typically range from the mid tens of thousands upward, depending on size, structure, tile and fixtures. Plumbing is what sets it apart from a kitchen or bedroom bump-out. You will need new drain lines, water supply and possibly venting changes. In Ontario, plumbing is a compulsory trade, so ask whoever does it to show their authorization; you can check the Skilled Trades Ontario Public Register.

Waterproofing is the critical detail. Shower moisture inside and winters that regularly reach well below -20°C outside create real condensation risk in the walls and floor. Ask your contractor which waterproofing membrane they use behind tile, how the shower pan is built, and how the bump-out cavity will be insulated and air-sealed so moisture does not condense inside the wall.

Drainage needs care too. The new floor must slope to the drain, and the drain has to tie into your existing drain-waste-vent system without back-pitch or poor venting. If the drain has to route through or under a slab, expect more work and cost, and ask for that to be itemized.

The City of Ottawa requires a building permit for additions and lists plumbing alterations, additions or extensions (except replacing existing fixtures) among permit projects. Permit fees are $12.75 per $1,000 of construction value, minimum $117. Electrical work such as a heated floor, fan or lighting needs an ESA notification or permit, handled by an electrical contractor licensed by ESA.

Ask for itemized quotes that separate structure, plumbing, waterproofing and finishes, and compare bathroom and addition contractors in the Ottawa Construction Network directory.

---

Looking for experienced contractors? The Ottawa Construction Network connects homeowners with qualified professionals:

• 613Bins
• JC Carpentry
• Rrenovatios
• Humble Homes - property maintenance
• Renovo Construction