The choice of wires in household renovations is a problem for many people。
Some people hit their heads and said that the house was a four square line, claiming that it was “safe and economical”; others insisted on the traditional practice of lighting 2. 5 squares, plugs 2. 5 squares and kitchens four squares。
The answer is clear from a security and economic point of view: it is better to use the wire in the right place, where it is not only a waste of money, but also a danger。
The “square” on the wire refers to the cut-off area of the copper core in millimetres。
The larger the area, the higher the currents the wires can withstand。
According to national standards, a copper line of 1. 5 squares can withstand 10 to 14 ampere currents, corresponding to a power of 2,200 to 3,000 watts; 2. 5 squares can withstand 16 to 22 amperes, supporting 3,500 to 4,800 watts; and 4 squares can reach 24 to 32 ampees, supplying 5,300 to 7,000 watts。
If home lighting, plugs and large power appliances all use a 4 squared brain, they appear to be more solid, but are typically “over-facing”。
This practice is motivated more by the profit of materials and the streamlining of construction: the electrician needs only one specification, saves the balance and has a modest gain on the material account。
From the construction site, it is true that there are a number of obvious problems with the 4 squared house。
The endpoints of the plugs often do not fit the 4 square lines, have to be cut or pressed and have a negative increase in exposure; the number of penetrating wires in the tubes has decreased significantly, and they are prone to heat dissipation due to the ultra-routing ratio; and the utility of the circuit breaker capacity in the distribution tanks is no longer meaningful if it does not rise to the corresponding specifications。
Further maintenance difficulties are associated with the need to draw lines at a later stage if the lines fail, and the 4 square lines are rigid like steel bars, which are difficult to pull in the bends。
When actually designed, matching by load is the core principle。
For example, regular lighting circuits, low energy consumption of led lamps, a household with a total lighting power of less than kw, and a 1. 5 square line is sufficiently safe。
The use of bedrooms and living room booths has not changed significantly, and the normal 2. 5 square formula with 16-anthropod breakers is stable。
The kitchen is more stable with 4 square feet for main drying due to the concentration of heavy loads of electric cooking, ovens and hot kettles, with branch circuits setting 2. 5 or 4 squares according to equipment power。
Air conditioners require independent circuits, with 1 to 1. 5 hangers using 2. 5 squares, and 3 cabinets or central air conditioners recommending a direct 4 squares。
The latest construction experience from 2025 to 2026 has shown that the safety flow of wires also requires environmental considerations。
High temperatures and poor air flow in the dark tube should not keep the current running long on the nominal full value。
It's common to leave 80%, or 80%。
If 2. 5 squares are called capable of carrying 22 an, the long-term safety value is only recommended between 12. 8 and 20 an。
The quality of the wire also varies widely, with parts of the product bearing the flag of the state, with a measured area of less than 2. 1 square millimetres, high resistance, high heat and shorter copper purity。
Now the market is pushing high-purity, non-oxidized copper, with a brand line certified by the ccc that is more reliable, like the far east and pandas in the middle-high-end series, and that, while expensive, the conductive power is stable, the temperature is low, and hidden engineering can actually be used for more than a decade。
The hierarchical protection of kitchens and air-conditioning circuits is becoming increasingly thin。
If the main kitchen main line is 4 squares, a further 2. 5 square branches can be pulled out, but high-power equipment such as embedded ovens, i. E. Hot cooks, is safe only with a separate 4 square circuit breaker。
With regard to air conditioning, 2. 5 squares are sufficient to cover a half-mounted machine, but three cabinets are high-powered, open up to 50 and 60 ang/h at short notice, and wires and switches should match larger capacity, and it is recommended to use 4 squares and corresponding c or d breakers。
As the lines get thicker, the problem with the tubes becomes more apparent. In the 16 mm or 20 mm pvc tube, the total area of wires should not exceed 40%。
The two 4 square lines plus one surface line cover almost all the pipes。
The use of 4 square feet for the house as a whole would require an increase in the number of pipes, a widening of the surface of the walls, and an increase in the number of people and materials, which would be harder to maintain in the future。
The norm requires that wires from the same circuit enter the same tube and cannot be mixed with different circuits, otherwise they are susceptible to sensory electrical interference and even electromagnetic cogeneration。
It is also related to heat dispersion and easier to rewire in the future。
Refurbishment of the site is also subject to congestion in the boxes。
Many of the coarse lines enter the same bottom box, making the pressure line more difficult, and there are frequent instances of uneven panels。
For the sake of ease of hand, some masters cut their copper cores or switched to end-end connections, with extended exposure to oxidation, resulting in unstable voltage and even burning。
The 2. 5 square line, which has a reasonable specification, is easier to bind in the bottom box, and the construction works well and safer。
Updates are also a trend。
Over the past few years, normal bv lines have been customised, and the wdz series, which is low-smoking and more fire-retarding, has been gradually promoted。
Such lines are less toxic when smoke occurs on short roads and are suitable for household and public buildings。
The entry line tends to use copper lines of six squares or even larger specifications to reserve space for future additions to the hot water heater or installation of new energy vehicle chargers。
The newly introduced safe life standards for appliances also remind that the design life of wires should match the life expectancy of appliances and that the risk of early ageing of old lines should be eliminated at the design stage。
The overall design orientation for household electricity is to be reasonably configured in the context of safety。
The lighting of 1. 5 squares is sufficient, and it can also be harmonized for 2. 5 squares if not purchased。
Both the bedroom and the living room outlets are the most economical with a 2. 5-square pair of 16-square breakers。
The kitchen pulls the 4-square main line from the distribution box, then follows the electrical branch to the different outlets, with the large power equipment taking an independent circuit。
Water heaters in the bathroom can be 2. 5 or 4 squares, i. E. The heat must be 6 squares with 40-separators。
The entry line starts with a six-square-square start, with appropriate margin based on projected power。
Bronze core hard wires are more suitable for piped installation than soft lines。
The work should be carried out with acoustics that are round and round, with an angle as low as 90 degrees and a fixed distance。
Each circuit will be provided with a separate line for electrical leak protection, with a clear pattern for different uses。
When the user communicates with the electrician, the other side knows that you are not white and that you are not easily miscalculated with material, provided that it is clear that there is a “safe surplus line by real power”。
There are concerns that the calculation alone is not insurable and that, in fact, the most important thing in a dwelling is not the thicker the wire, but the better the match. 2. 5 square is the main player in the family line, with most loads ranging from hundreds to three kilowatts. Four squares are suitable for kitchen main lines and high power equipment. Six squares for bus or superpower scenario。
The 4 square feet of the house are significantly wasted unless all electrical appliances in the home are operated at the same time with high power。
Home appliances are hidden works, and problems are greatest when they are not seen for more than a decade。
Much of the over-advertising in the market for “safer with thick wires” is to capture the uncertainty of users about safety。
A true scientific approach that follows the norms, selects a credible brand, calculates the actual electricity load and leaves a sufficient amount of it behind, is more secure than a desire for a thick line。
The demand for electricity in households will increase in the coming years, and electrical choice can be considered in the longer term。
Households planning to install storage, photovoltaic or new energy vehicle recharge poles are advised to leave larger sections of the main line and distribution tank at the design stage to avoid a later breakback。
For ordinary households, scientific mixing of 2. 5 squares and 4 squares, combined with strict partitioning, compliance installation, and flood-proof ageing, is sufficient to cope with a safe use cycle of more than 10 years。
The choice of high-quality copper cores and flame-retardant materials, if well budgeted, can significantly increase the useful life。
Essentially, the power lines in the home renovations are not as expensive as they are and not as thin as they are, but are well matched。
Ideally, high value for money within the margin of safety, where money is spent at key points, rather than being influenced by marketing concepts。
Each line is as important as the blade to keep the lights on, the plugs steady and the machine calm, which is the way to make sure it's done。
