6 min read · Updated August 10, 2026
A repipe in a vacant building is a plumbing project. A repipe in an occupied building is a logistics project that happens to involve plumbing, and the proposals that fail are almost always the ones that priced the pipe and ignored the logistics.
The questions that belong in the proposal
How is the work phased? Unit by unit, stack by stack, or floor by floor. This determines how long the whole project takes and how many residents are affected at once.
How long is water off, per unit, per day? Not “a few hours.” A stated window, on stated days, so you can give residents accurate notice.
What notice period does the schedule assume? Your entry-notice obligations are set by your lease and by law, not by the contractor. A schedule that assumes less notice than you can legally give is a schedule that will slip.
Where is wall access required? Every access point should be identified before the contract, not discovered during it.
Who patches and who finishes? Access patching and finish restoration are separate scopes from plumbing. Whether they are included, excluded or subcontracted needs to be explicit. This is the single most common source of disputes on repipe projects.
What happens to units that cannot be accessed on their scheduled day? There is always at least one. The rework policy should exist before you need it.
What is the inspection sequence? Rough inspection has to land between installation and closing the wall. If that is not planned, the schedule stops.
What to prepare on your side
- Confirm your legal entry-notice requirement and build it into the schedule
- Identify units with access constraints: pets, medical needs, work-from-home residents, hoarding conditions, units with locks the office does not have
- Decide how residents get water during shutoff windows and communicate it in advance
- Plan for laundry and common-area impacts if those are on affected risers
- Decide who residents call with questions — you or the contractor — and say so in the notice
- Photograph unit conditions before work starts
What good documentation looks like at the end
- Per-unit record of what was replaced and when
- Photographs of access points before closing
- Updated shutoff map with labelled valves
- Inspection records
- A punch list that was actually closed out
That record is what makes the next ten years of maintenance on the building cheaper, and it is the part most contractors leave out because nobody asked for it.
The realistic framing
Repiping an occupied building is disruptive, and a contractor who tells you otherwise is either inexperienced or selling. The goal is not to make it painless. It is to make it predictable, so that residents get accurate information and you are not fielding surprises.
This article is general information about how plumbing systems behave. It is not a diagnosis of your building, and it is not instructions for performing regulated work. Gas, electrical, pressurised systems, sewage contamination and code-regulated work belong with the appropriate licensed trade.