Water and drainage: lifespan and cost

Pipes and drains are hidden until they leak, and then it gets expensive. The table shows how long different pipes last and what replacing them usually costs.

The ranges apply to a normal-sized house. Actual cost depends on size, access and region. Lifespan means technical lifespan with normal upkeep.

Component	Lifespan	Replacement cost
Copper pipes, cold water	50 yrs (40-60)	50 000-150 000 kr
Copper pipes, hot water	32 yrs (25-40)	50 000-150 000 kr
PEX pipes	50 yrs (40-60)	40 000-120 000 kr
Galvanised pipes	35 yrs (30-40)	60 000-180 000 kr
Cast iron drains	60 yrs (50-100)	100 000-300 000 kr
PVC drains	40 yrs (30-50)	80 000-200 000 kr
Risers in apartment buildings	45 yrs (30-60)	200 000-500 000 kr
Hot water heater	15 yrs (10-20)	15 000-40 000 kr

How long do water pipes last?

Copper pipes last a long time, but the hot water line wears faster than the cold because heat is harder on the metal. PEX pipes are modern plastic pipes, often run inside a conduit so a leak shows and can be replaced without breaking open walls. Galvanised pipes are the oldest and rust from the inside; in older houses they are often near the end.

What does replacing drains and risers cost?

Cast iron drains rust and can crack over the years, and replacing them often means opening floors and walls. In apartment buildings the pipes gather into risers, and a pipe replacement is one of the largest projects an association takes on. In a house the scope is smaller but the logic is the same: the cost is the access. See the dedicated page on pipe replacement for intervals and cost.

What the age of the house tells you

Some build years carry known risks for exactly these parts. Here are the most common ones.

Asbestos Houses built 1930–1982

Asbestos was widely used during this period. Sampling is required before renovation.

Copper pipes with corrosion risk Houses built 1965–1985

Early copper installations had quality problems. Pitting corrosion is common, especially in hot water pipes.

Cast iron drains Houses built 1920–1970

Cast iron drains rust from the inside. Service life 50-70 years. Ask whether relining or replacement has been done.

How do I know how old the pipes are?

Ask the agent for the year of any relining or pipe replacement, and look in the boiler room and under the sinks for markings. Pipes from the build year that have never been replaced are a clear upcoming cost.

What is relining?

Relining coats the inside of existing drains with a new layer instead of replacing them. It is less invasive than a full pipe replacement, but does not last as long and does not suit every pipe.