The electrical panel is where all of a home's wiring comes together and gets protected by breakers. When a panel is picked by eye, or the cheapest option with the fewest module slots is bought, it's almost guaranteed that within a couple of years there won't be room for a new breaker — and any new circuit, whether for an air conditioner, underfloor heating, or a stove outlet, ends up forcing a full panel replacement.
Here's what a panel is made of, how to work out how many modules you actually need, and what to pay attention to when choosing one — whether you're fitting a panel in an apartment, a house, or moving it to a new spot.
What's inside an electrical panel
A standard panel for an apartment or house typically includes:
- a main breaker — the overall switch for the whole panel;
- RCDs or RCBOs — protection against current leakage, usually per group or for the whole panel;
- circuit breakers for each group — separate lines for outlets, lighting, the kitchen, the bathroom, and high-power appliances;
- busbars — to distribute phase, neutral, and earth between the breakers;
- space for the meter — if the meter sits in this same panel rather than on the landing.
The more independent groups a home has, the easier it is to isolate a fault later: if the kitchen loses power, you won't need to cut electricity to the whole apartment just to figure out why.
Flush-mounted or surface-mounted panel
A flush-mounted panel sits in a recess cut into the wall and barely projects from the surface — a neat option for an apartment, especially when the panel is being replaced during a renovation and there's room to prepare the recess. The downside is that expanding it later is harder if you run out of modules: you'd need to widen the recess or add a separate box.
A surface-mounted panel is fixed directly to the wall. It sticks out a few centimeters, but it's easier to install without chasing the wall, and it's usually simpler to add modules to later. Surface-mounted panels are common in private houses, garages, and utility rooms — places where appearance matters less than in a living room.
How many modules you need — counting the groups
The number of modules a panel needs is driven by the number of circuit groups, not directly by the floor area. Circuits are typically split out for: lighting (per room or combined), outlets in living rooms, kitchen outlets, a dedicated line for an electric stove or oven, a dedicated bathroom line (with an RCD), a line for the washing machine, and, where relevant, air conditioning and underfloor heating.
Rough module counts by home type:
| Home type | Approx. number of groups | Recommended panel modules |
|---|---|---|
| Studio / 1-bedroom apartment | 4-6 | 12-18 |
| 2-3 bedroom apartment | 6-10 | 18-24 |
| Private house (excluding heating) | 10-16 | 24-36 |
Exact figures depend on the layout and the set of appliances involved — treat this as a starting point for a conversation with an electrician, not a fixed formula.
Leaving room for future modules
If a panel is filled to match only today's needs, any future change — buying an air conditioner, adding underfloor heating in the bathroom, moving an outlet for new equipment — will mean either mounting a small separate box next to it or replacing the panel entirely. A reasonable margin is 15-25% of spare modules beyond current needs, especially if the renovation is meant to last for years and you'd rather not redo the panel a year or two later.
Enclosure material and protection rating
A plastic enclosure is the standard choice for an apartment: it's lighter, cheaper, and perfectly adequate in a dry room. Metal enclosures are more common in private houses, at the incoming supply point, or anywhere extra mechanical strength matters.
For damp rooms (bathroom, utility room), a garage, or outdoor installation, the IP protection rating matters — the higher the numbers after IP, the better the panel is sealed against dust and moisture. A panel meant for a dry apartment shouldn't end up in a garage or outdoors — that's a safety issue more than a cosmetic one.
Common mistakes when choosing a panel
The most common mistakes: buying a panel with exactly the number of modules needed today and no spare capacity; lumping unrelated loads into one group — say, the kitchen and bathroom on the same breaker; installing a panel with no wiring diagram, so that six months later nobody remembers which breaker controls what; and skimping on RCDs in rooms with higher humidity.
Panel layout and specification is one of those things worth working out properly with an electrician once, rather than redoing later.