Montlake is one of those Seattle neighbourhoods where almost every house has a story behind its walls. Most of the homes went up between the wars, packed onto the narrow strip of land between Portage Bay, the Montlake Cut and the edge of the Arboretum, and very few of them still have the plumbing they were built with. What they have instead is layers: an original drain stack here, a bathroom added in the sixties there, a kitchen that has been redone two or three times. Anyone planning new fixtures, a second bathroom or a full repipe in one of these houses is really planning around that history.
This piece walks through what tends to come up when new plumbing goes into an older Montlake home, and how owners can keep the project from turning into a string of surprises.
What the housing stock means for new work
The brick Tudors, Colonial revivals and Craftsman bungalows that line streets like Boyer and the blocks north of Roanoke were solidly built, but they were plumbed for a different way of living. One bathroom upstairs, a laundry tub in the basement, maybe a half bath tucked under the stairs. Adding to that means finding room for new supply lines and, more importantly, for drains that have enough slope to work.
Basements are usually where the answers are. Many Montlake houses have full or partial basements with a mix of cast iron, galvanized steel and later copper running along the joists. Before a single new fixture is chosen, it is worth having someone trace where the main stack runs, how the vent system is laid out and whether the existing drain can take more load. That survey decides what is practical far more than any catalogue does.
Old pipe meeting new pipe
The tricky part of most jobs here is the joint between old and new. Galvanized supply lines narrow on the inside as they age, so tying a new bathroom into a tired galvanized branch can leave the new shower with weak pressure no matter how good the fixture is. Cast iron drains can be in decent shape for their age or can be thin and scaled; the only way to know is to look, often with a camera. Owners who plan to keep the house for a long time often decide to replace the supply side back to the main shutoff while the walls are open anyway, rather than paying to open them twice.
Ground, water and the lower blocks
Montlake sits close to water on three sides, and the lower streets toward Portage Bay and Union Bay feel it. Basements on those blocks can be damp, and anything new that goes below the main floor needs some thought about where the water goes. A basement bathroom, for instance, may sit below the level of the side sewer, which means a pump or ejector rather than a simple gravity drain. On higher ground toward the Arboretum side, gravity is usually on your side, but older clay side sewers and big street trees bring their own problems with roots.
None of this is a reason not to build. It is a reason to ask about drainage and backflow early, before the layout is locked in.
Planning the job so the house stays livable
Most Montlake owners are living in the house while work happens, and the narrow streets and tight lots near the 520 interchange make staging awkward. A few habits help:
- Agree on when the water will be off and for how long, and plan around it.
- Decide early whether fixtures will be bought by the owner or the plumber, so rough-in measurements match what actually arrives.
- Ask how access panels will be handled for any new valves hidden in walls.
- Keep the permit and inspection steps in the schedule rather than treating them as an afterthought.
There is a useful piece on how a job gets scoped before anyone opens a wall, which is worth reading before collecting quotes.
Kitchens, laundry and the fixtures people actually add
The most common requests in houses like these are a second full bathroom, a laundry moved up from the basement, and a kitchen with an island sink. Each one runs into the same constraint: the drain has to go somewhere. An island sink needs a vent solution because there is no wall behind it. A second-floor laundry needs a pan and a drain under the machine, and the floor framing in a century-old house may need a closer look. A new bathroom over a finished room downstairs means thinking about how you would reach a leak if one ever showed up.
For homes with rental units or a basement apartment, the same questions apply with a twist, and it is worth reading about planning work in a building that's still occupied before committing to a schedule.
Who to call and what to ask
When you talk to plumbers, ask whether they have worked in pre-war houses on this side of the Ship Canal, how they handle the transition from old to new materials, and what they would want to inspect before giving a firm number. A crew that wants to look in the basement and crawl the attic before quoting is usually one that will not be surprised halfway through.
For a neighbourhood-specific starting point, there is a page covering Montlake at www.plumberseattle.us.com/plumber/montlake that goes over the area and the kind of work that comes up in these homes.
The houses here have lasted a long time because people kept taking care of them. Adding plumbing the careful way, with the old system understood before the new one goes in, is how they keep lasting.