How do I handle a bathroom renovation in a Vancouver strata unit that shares a wet wall with another unit?

A shared wet wall in a strata bathroom renovation is one of the most technically and legally complex scenarios in Metro Vancouver — you need strata approval, a licensed plumber, proper waterproofing, and a clear understanding of where your unit ends and common property begins before a single tile comes off the wall.

A wet wall shared between two strata units contains supply lines and drain stacks that may serve both units simultaneously. Disturbing this wall without proper planning can interrupt your neighbour's water service, damage common property, and expose you to significant liability. This is not a project to approach casually.

Start With Strata Approval — Before Anything Else

Written strata council approval is mandatory before any work begins. Most Metro Vancouver strata corporations require a detailed renovation plan that includes the scope of work, contractor information, proof of liability insurance (minimum $2 million), and a WorkSafeBC clearance letter. For a shared wet wall specifically, your strata may also require a plumber's assessment of the existing stack and supply configuration before approving the renovation at all.

Check your strata's bylaws carefully. Many buildings have specific rules about wet wall work — some prohibit relocating plumbing fixtures entirely, others require a licensed plumber's sign-off at every stage, and some require the strata's own plumber to inspect the shared wall before and after work. Failure to obtain written approval before demolition begins can result in stop-work orders, fines of $200 per day or more, and personal liability for any damage to your neighbour's unit or common property. Get everything in writing.

Understanding What's in That Wall

A shared wet wall typically contains the main drain stack (a vertical ABS or cast iron pipe running the full height of the building), horizontal drain branches serving your fixtures, hot and cold supply lines, and potentially vent pipes. In Metro Vancouver's older condo stock — buildings from the 1980s and 1990s in Burnaby, New Westminster, and North Vancouver — you may also encounter copper supply lines with aging compression fittings that are overdue for replacement.

Before demolition, have a licensed plumber assess the wall. They can identify which pipes serve your unit exclusively versus which are shared common property. In most BC strata corporations, the main drain stack and any pipes serving multiple units are common property — you cannot modify them without strata authorization, and any damage to them during your renovation is your financial responsibility. Your plumber should also check for asbestos-containing pipe insulation if the building predates 1990, as disturbing it requires professional abatement before any other work proceeds.

Waterproofing Is Non-Negotiable — Especially on a Shared Wall

Because a shared wet wall is typically an interior wall with no ability to dry toward the exterior, waterproofing on this surface is even more critical than on an exterior bathroom wall. Any moisture that penetrates tile grout or a failed caulk joint on a shared wet wall has nowhere to go — it saturates the wall cavity, migrates toward your neighbour's unit, and creates mould conditions that affect both units.

Schluter Kerdi membrane applied directly to cement backer board (never drywall or greenboard) is the industry standard for this application in Metro Vancouver. The membrane must be continuous across the entire wet area — walls and floor — with Kerdi-Band at all corners and seams. Liquid-applied membranes like RedGard are an alternative but require meticulous application at corners and penetrations. Budget $1,500–$4,000 for proper shower waterproofing in a standard strata bathroom. Your strata may actually require waterproofing documentation as part of their approval process — some buildings in Vancouver and Burnaby now require a third-party waterproofing inspection before tile is installed.

Practical Steps for Your Project

Hire a licensed plumber to assess the shared wall and confirm what can and cannot be modified. Get written strata approval with your full renovation plan before demolition. Ensure your contractor carries $2 million liability insurance and active WorkSafeBC coverage — request both documents before signing anything. Use cement backer board on all wet surfaces and a continuous waterproofing membrane behind all tile. Document the waterproofing installation with photos before tile goes up — your strata may require this, and it protects you if a neighbour ever claims water damage.

Budget 10–20% above a comparable non-strata renovation for the additional insurance, documentation, restricted work hours, and coordination requirements that come with strata work in Metro Vancouver.

Vancouver Bathrooms can match you with bathroom renovation contractors experienced in Metro Vancouver strata projects — find local professionals through the Vancouver Construction Network at vancouverconstructionnetwork.com/directory?trade=bathroom-renovations.