What's involved in converting a half bath to a full bathroom in a wartime bungalow in East York?

Converting a half bath (powder room) to a full bathroom in an East York wartime bungalow involves adding a shower or tub, which requires new plumbing rough-in for the shower drain and supply lines, waterproofing, tile work, upgraded ventilation, and typically costs $15,000 to $30,000 in the current GTA market. It is one of the most impactful renovations you can do in these charming but compact homes.

East York's wartime bungalows — built primarily between 1942 and 1955 across neighbourhoods like Woodbine Heights, Topham Park, and Eastdale — were designed as modest, efficient homes with small footprints. Many have a single three-piece bathroom and, if you are lucky, a half bath that was either original or added later. Converting that half bath to a full bathroom with a shower transforms the home's functionality, especially for families or for aging-in-place planning.

Space Assessment

The first challenge is space. A half bath in a wartime bungalow typically occupies 16 to 25 square feet — enough for a toilet and a small pedestal or wall-mounted sink, but tight for adding a shower. The minimum practical shower size is 32 x 32 inches (a neo-angle or corner unit), though 36 x 36 inches is far more comfortable. A standard alcove tub/shower combo requires a space at least 30 inches wide by 60 inches long, which is rarely available in a wartime bungalow half bath without expanding the room.

Your options typically include: expanding into adjacent space by borrowing square footage from a hallway, closet, or bedroom — even 18 to 24 inches of additional depth can make the difference; installing a compact corner shower or a neo-angle shower base designed for tight spaces; or reconfiguring the existing layout to optimize every inch. A skilled contractor who has worked on East York bungalows will have experience with creative layouts in these exact floor plans.

Plumbing Requirements

Adding a shower requires new drain and supply rough-in. The shower drain (2-inch minimum) needs to connect to the existing drain-waste-vent (DWV) system with proper slope — 1/4 inch per foot of horizontal run. In a bungalow built on a concrete slab (common in wartime construction), this may mean cutting the concrete floor to run the new drain line, which adds $1,500 to $3,000 to the plumbing cost. If the bungalow has a crawlspace or basement, the plumber can often run the drain below the floor joists, which is less invasive and less expensive.

New hot and cold supply lines must be run to the shower location, and a shower valve (pressure-balance or thermostatic, as required by the Ontario Building Code for anti-scald protection) must be installed. The existing half bath's supply lines may need upgrading — wartime bungalows often have original galvanized steel pipes that should be replaced with copper or PEX while the walls are open.

A plumbing permit from the City of Toronto is required for the new shower drain and supply connections. The rough-in plumbing must pass inspection before walls are closed.

Waterproofing, Tile, and Ventilation

Waterproofing is non-negotiable for any new shower installation. The shower walls and floor must have a continuous waterproof membrane — Schluter Kerdi sheet membrane or a liquid-applied membrane like RedGard — covering the entire wet area from the shower floor to at least 6 inches above the showerhead height. This is the single most critical element of the project; failed waterproofing leads to hidden mould and structural damage.

The shower walls require cement board backer (Durock, Wonderboard, or DensShield) rather than standard drywall. Tile installation in the shower area typically costs $10 to $25 per square foot installed depending on tile selection and pattern complexity.

Ventilation must be upgraded — a half bath may have had minimal ventilation or just a window, but a full bathroom with a shower requires a minimum 50 CFM exhaust fan vented to the exterior. An electrical permit and ESA inspection are required for the new fan circuit, any new GFCI outlets, and shower lighting.

Expect the project to take 2 to 4 weeks of construction time, plus planning and permit timelines. Browse bathroom renovation professionals through the Toronto Construction Network directory at torontoconstructionnetwork.com to find contractors experienced with East York bungalow conversions.