What kind of pipe do you actually have?

Start in the mechanical room.

That is usually where the building gives you the clearest look at exposed piping. From there, check under several suite sinks on different floors rather than assuming one suite represents the whole property.

Older multifamily buildings often contain more than one material after decades of repairs and partial replacements. Finding copper under one sink tells you about that sink. It does not prove the entire building is copper.

What the common materials look like.

Poly-B

Poly-B is commonly grey, though black or white versions exist. It is flexible and matte and is often joined with crimp rings. Source material notes that pipe may carry a PB2110 marking. If you confirm Poly-B, treat it as a building-wide planning question rather than assuming isolated repairs describe the remaining system.

Kitec

Kitec commonly appears as bright orange hot-water tubing and bright blue cold-water tubing with brass fittings. Some Kitec fittings are stamped KTC, and the product may appear under several alternate names. The important scoping question is not only whether Kitec exists, but where it runs and whether any heating lines are embedded in a slab.

Galvanized steel

Galvanized steel is rigid, dull grey, threaded at joints, and magnetic. The source describes internal corrosion and scale as the long-term problem, with reduced flow or pressure often appearing before a visible leak.

Copper

Copper is rigid, penny-coloured when freshly scratched, and commonly soldered at joints. Repeated pinhole leaks across a property should be documented as a system pattern rather than dismissed as unrelated one-off events.

PEX

PEX is flexible and often red or blue, with several fitting systems. In an older building, finding PEX may indicate partial replacement work already happened. Record where it is present and, when possible, when that work was completed.

Lead

The supplied guide describes lead as soft grey, non-magnetic, and easy to scratch to shiny silver. If you suspect lead, have the material professionally confirmed rather than making a capital plan from a visual guess.

Do not forget the drains.

Supply piping gets most of the attention in a repipe conversation, but the source specifically warns against ignoring aging drain systems while you are already inventorying the building. Cast iron, ABS, PVC, and other drain materials belong in the record too.

Then write it down.

A short building record of what material exists where, which suites have been partially repiped, and what remains unknown is useful for project planning and future board or management handoffs.

If the building is mixed or the visible areas do not give you enough information, that uncertainty is itself a useful finding. That is the point to move from a flashlight inspection to a building assessment rather than guessing from two sinks.

Use this guide as a starting point. Confirm pipe material with a qualified professional before making building decisions.