Water pipe replacement

When should water pipes be replaced?

Domestic water pipes, meaning the cold and hot water pipes, last for decades, but the material and the water quality have a big effect on their lifespan. Older buildings may still have galvanised steel pipes that rust from the inside, narrowing the bore of the pipe. With copper pipes, the problem can be pitting corrosion, which causes small leaks.

A single leak does not mean the whole pipework needs replacing. But if there have been several leaks, or the rest of the pipes are as old as the repaired section, replacement often costs less in the long run than repeated repairs and water damage. Replacement is especially worth considering if you notice any of the following signs:

• the water is brown or yellowish, especially in the morning or after a longer break
• the water pressure has dropped even though the aerators on the taps (faucets) have been cleaned
• leaks, damp marks or greenish oxidation are visible on pipes or joints
• the pipes are original and no pipe renovation has been done in decades

Copper or composite, surface-mounted or concealed?

The most common pipe materials are copper and composite pipe, a multilayer pipe with an aluminium layer between plastic layers. Copper is a durable material, and its joints are soldered or made with press fittings. Soldering is hot work, for which the installer holds a hot work card (Tulityökortti). Composite pipe is light and flexible, and it is joined with press fittings.

With surface mounting, the pipes are fixed to the surface of the wall or ceiling and can be boxed in if needed. The installation is faster, and any leak is easy to spot. With concealed installation, the pipes run inside the structures in a protective sleeve pipe, so they can be replaced without opening up the structures. The system is built so that any leaking water becomes visible, and PEX or composite pipe is usually used. Concealed installation suits a larger renovation, but it requires more building work.

It is also worth thinking about the positions of water points and shut-off valves. When each fixture has its own shut-off or angle valve, a single tap or toilet can later be replaced without shutting off the water to the whole house.

Detached house or housing company?

In a detached house, you decide yourself when and how the pipes are replaced. Domestic water pipes are often worth replacing when the bathroom or kitchen is renovated, because the structures are already open. Wet-room waterproofing, however, is a separate job done by a certified waterproofing specialist.

In terraced and apartment housing companies, domestic water pipes are usually the housing company's responsibility, and replacing the pipes in the whole building is carried out as a pipe renovation (linjasaneeraus), the housing company's own project. As a flat owner, you can still have plumbing work done in your own flat, for example during a bathroom renovation. First submit a renovation notice (muutostyöilmoitus) and wait for the housing company's reply, as it can set conditions for the work. If your flat has no shut-off valves of its own, the water shut-off is arranged with the maintenance company (huoltoyhtiö).

Price and household tax credit

Water pipe replacement is priced as a quote. The price depends on the metres of pipe, the number of water points, the pipe material, the installation method and whether boxing-in or opening up structures is needed. If you want to replace your taps and shower at the same time, for example, mention it in your quote request.

The household tax credit (kotitalousvähennys) is currently 35% of the labour cost. The annual threshold you pay yourself (omavastuu) is €150 and the maximum deduction is €1,600 per person per year. If spouses pay for the work together, each can claim the deduction for the share they paid. In a housing company, water pipes are usually the company's maintenance responsibility, and then replacing them does not qualify, even if the shareholder pays – only extra work you order and pay for directly to the contractor can. The government has proposed a temporary increase for 2026–2027, so check the current information on vero.fi. See the worked examples in our household tax credit guide, or make your own estimate with the calculator on our prices page.