The electrical system is one of the core elements of building services, and like other systems, it ages over time. But why is renovation important, what does it actually involve—and how much does it cost?
Why does the electrical system need to be renewed?
The technical service life of an electrical system is typically around 30–40 years. After that, it may no longer meet current safety and capacity requirements.
Over the decades, electricity use has changed significantly. The load has increased due to household appliances, electronics, and electric vehicle charging. At the same time, usage habits have evolved: modern homes have considerably more power outlets and electrical devices than apartments built in the 1950s and 1960s.
An aging and overloaded system can pose a fire safety risk. For example, the lack of grounding and residual current devices can create hazardous situations—these became mandatory only in the 1990s.
A new electrical system not only improves safety but also ensures sufficient capacity for today’s and future needs.
How does the renovation proceed?
The electrical system can be renovated either as a standalone project or as part of a larger renovation, such as a plumbing and drainage overhaul.
The first phase is planning, during which the current condition of the system and future needs are assessed. Plans are then drawn up, contractors are put out to tender, and bids are requested. The final decision is made at the shareholders’ meeting, and once approved, the project moves on to the implementation phase.
Implementation Options
The scope of the renovation can vary. Often the entire system is renewed, but partial renovation is also possible. For example, only the building’s electrical distribution system may be replaced, or alternatively only the electrical installations within the apartments.
Renewing the electrical distribution system typically includes replacing the main switchboard and the service connection cable, upgrading the rising mains, and updating the apartment distribution boards. At the same time, it is advisable to renew lighting and power outlets in common areas and, if necessary, also the telecommunications and antenna networks.
One implementation model is a design-and-build contract (KVR, “design and construct”), in which the contractor is involved in the planning from the very beginning. This can result in significant cost savings.
Preparing for the future
When carrying out a renovation, it is wise to take future needs into account as well.
For example, electric vehicle charging infrastructure can be installed right away, but even preparing the system for later expansion can be a sensible and cost-effective solution to implement as part of an electrical renovation.
Solar power generation can also be integrated into the project, supporting energy efficiency and reducing the property’s electricity costs in the long term.
Even if no immediate investments are made, it is advisable to reserve capacity in the new electrical switchboards for future needs.
How much does an electrical renovation cost?
The costs depend on the scope and content of the work. Planning is often one of the most significant factors affecting the overall price, but a skilled contractor can also identify cost-effective solutions.
Labor and material costs make up the largest share of the contract price. The cost of construction materials rose sharply in recent years, but fortunately the increase has leveled off after 2024.
Price example:
A typical comprehensive electrical renovation of a 28-apartment apartment building—where the electrical distribution system, antenna and general cabling, and the apartment electrical systems are renewed—costs the housing company approximately €400,000–€560,000 including VAT. This corresponds to about €12,000–€16,000 per apartment.
The price can be lower in larger properties or if the renovation is carried out with a more limited scope. For example, in Puotila, Helsinki, we carried out an electrical renovation in which the apartment electrical systems were partially excluded from the contract. In the common areas, the property’s electrical supply, main switchboards, and rising cables were renewed. In the apartments, the distribution boards, antenna and general cabling outlets, and the supply cabling for the stove and dishwasher were replaced. This approach allowed the most heavily loaded parts of the electrical system to be upgraded to new and safe ones. The housing company, comprising more than 300 apartments, managed to reduce the per-apartment cost to approximately €9,400.
Terawatt – an experienced electrical renovation specialist
As always, when selecting a contractor it is important to pay attention to the company’s financial stability and references. Terawatt has already carried out more than 110 electrical renovations for housing companies and other properties. Our experience, solid financial standing, and professional personnel ensure smooth execution of the project from start to finish.
Our customer satisfaction speaks for itself: in 2024, our NPS score was 64. Our employees also stay with us for a long time—and that shows in the high quality of work delivered to our customers.
An electrical renovation is always a major project, but with an experienced and reliable contractor, the client has one less thing to worry about. Our principle is simple: we agree on what will be done—and we do exactly what we agree on.
Planning an electrical renovation?
Get in touch, and let’s go through how we can help with renewing your property’s electrical system!
