The most common mistakes in home installations. Check if you're making them.
, by Tomasz Sawicz, 4 min reading time
Electrical installations are something we rarely think about on a daily basis—until a problem arises. Poorly selected wiring, a lack of adequate protection, or too few circuits are all mistakes that can lead to failures and even serious hazards. In this article, we present the most common mistakes made in electrical installations and suggest how to avoid them. This will ensure your installation is not only convenient to use but, above all, safe for the household.
The electrical installation is the heart of every home and apartment. Its quality determines safety, everyday comfort, and the trouble-free operation of equipment. Unfortunately, in practice, many people, both those doing the work themselves and novice professionals, make mistakes that can lead to costly breakdowns and even life-threatening situations.
In this article, we present the most common electrical installation errors and suggest how to avoid them.
1. No installation plan
The biggest problem is starting work without a design and carefully planned circuit layout. This results in poorly placed outlets, too few light points, or overloaded circuits.
👉 Solution: before starting the installation, it is worth preparing a project, and in the case of modernization, carefully analyze the current needs and predict future ones (e.g. for photovoltaics, air conditioning).
2. Using cables with the wrong cross-section
Wires that are too thin heat up quickly and can cause a fire. Wires that are too thick are an unnecessary expense.
👉 Solution: Always choose a wire that's appropriate for your circuit type and load power. For general outlets, 2.5 mm² wires are most commonly used, while for lighting, 1.5 mm² wires are most commonly used.
3. No residual current device (RCD)
It still happens that home installations lack differential protection. This is a serious mistake. An RCD protects against electric shock and should be standard in every distribution board.
👉 Solution: Use differential circuit breakers (e.g., E-NEXT), which effectively increase household safety and help protect your appliances from damage. You can find them on our website.
4. Connecting twisted pair cables
Unprofessional connection of wires using twisted pairs and insulating tape is one of the most common and dangerous practices. Such connections can become loose and lead to short circuits.
👉 Solution: use appropriate connectors (e.g. WAGO) or installation boxes.
5. Too few circuits
Many older electrical installations operate on two or three circuits for the entire home. In practice, this means that the outlets in the kitchen, bathroom, and living room are connected to a single circuit breaker.
At first glance, this works—but only until we turn on several high-powered appliances simultaneously, such as a washing machine, kettle, and oven. Then, it's very easy to overload the wires, which, if used incorrectly, can even cause a fire, or voltage drops that cause lights to flicker, and in extreme cases, can even damage the equipment.
👉 Solution: several circuits, especially separate ones for the kitchen and bathroom, dedicated lines for energy-intensive devices (washing machine, dryer, induction)
6. Incorrect wiring
Although it seems impossible, it's not uncommon for cables to be run diagonally or too shallowly under the plaster. This makes subsequent renovations or alterations difficult and significantly increases the risk of cable damage, for example, when drilling holes.
👉 Solution: Always run cables vertically and horizontally in relation to the walls and at the appropriate depth.
7. Lack of space for expanding the installation
Many investors install switchboards "on the spot," without any spare modules. Problems arise when the need arises to connect photovoltaics or an electric car charger. When designing the installation, it's important to consider possible future expansions. A larger switchboard, given the cost of the entire installation, won't break the bank, and in the case of a modernization, it can even help save money (it will eliminate the need for reconstruction).
👉 Solution: Choose distribution boards with ample space for additional modular devices. These distribution boards are available in our offer.
8. Documentation of works and cable routes
This is a point few people think about. It's often underestimated, but such a small detail can make future work in the apartment or house easier. It's worth knowing exactly where which wires run in the walls.
👉 Solution: drawings of the wiring routes and connection points. During renovation work, simple photos taken with a phone will work just as well.
In summary, electrical installation requires an investment not only of money but also of time. It's a crucial element in a home, and it's not worth skimping on. Proper planning and execution will ensure not only convenience but, most importantly, safety.
