Renovation of a prefabricated apartment: what to watch out for

Load-bearing panels: where does the limit lie?

In a panel building, the walls bear the load, not the skeleton as in new-builds, what looks like an ordinary partition may be the load-bearing structure for the entire floor above you. Therefore, demolishing or even just enlarging an opening in a load-bearing wall is not a matter for a skilled bricklayer, but for a structural engineer.

As a general rule, any work affecting load-bearing structures requires a project design and, depending on the scope, either a notification or a building permit. The exact procedure and what your specific intervention requires will be assessed by a designer or an authorised structural engineer, not estimated visually by a construction company. Verify this before deciding on a layout change, as amending a project afterwards can delay the entire schedule by weeks.

In practice, this means: if you are planning only a cosmetic or partial renovation of a panel flat without changing the layout, structural integrity is not your concern at all. As soon as words like "connect", "enlarge" or "demolish" appear in relation to an internal wall, it is time to call a designer before contacting a construction company.

Aluminium ductwork: a silent problem in older flats

Flats from the 1960s and 1970s often have electrical wiring using aluminium conductors instead of copper. Aluminium itself does not burn, but aluminium-copper connections gradually corrode, increasing contact resistance and with it the risk of overheating at the joint, which is usually only discovered by a blackened socket or a tripping circuit breaker.

When renovating a flat in a panel building, replacing aluminium wiring with copper is one of the items most frequently appearing as extra work, since the condition of the electrical installation can only be reliably determined once walls are opened. If the flat does not have an inspection report from recent years, expect that this replacement will appear in the budget, better at the start than as an unpleasant surprise halfway through the project.

Riser pipes: why they concern more than just you

Water supply and waste risers run through the entire vertical column of flats above one another, so their replacement does not concern only your flat, coordination with neighbours and the building's owners' association or housing cooperative is required, as the work entails a water shutdown for the entire riser line, not just at your premises.

• Check with the building's owners' association whether replacing risers is planned as part of the building's revitalisation: in that case, it makes sense to wait or align with the shared schedule.
• Notify neighbours in advance of the water cut-off: typically this is arranged through the building's owners' association committee, not by email from your construction company.
• Old cast-iron risers are nowadays commonly replaced with plastic, once the riser is opened at your premises, it presents the most cost-effective opportunity to also replace the section on your floor, provided the building's owners' association agrees.

Old floor covering

Panel flats from the turn of the 1970s and 80s often have flooring under old lino or PVC based on asphalt rolls, indistinguishable from ordinary vinyl at first glance. Removing such flooring requires a different procedure than standard floor demolition, as it is not treated as ordinary construction waste. If the flat dates from this period and no one has addressed the floors since completion, it is worth asking companies in advance. They handle this routinely, but it is better to have it stated in the offer rather than discovering it during demolition.

A panel building does not forgive improvisation with load-bearing walls and utilities, where a brick house might overlook it, a panel building will reliably make it more expensive.

What this means for choosing a company

Renovating a flat in a panel building requires a company with references specifically for panel buildings: not just general "flat renovation" experience. Experience with umakart cores, aluminium distribution systems and coordination with the building's owners' association is a different skill set than renovating a brick flat in the city centre. This is precisely what we ask before recommending a company further; you can find more on how to spot an amateur yourself in our article about red flags at a construction company.

Are you dealing with just a bathroom? Read on. price and difference between an Umakart core and a masonry core.