If you are faced with the need replacement of the plumbing system in the apartment, then you will have to purchase suitable parts - pipes and fittings. After the difficult question of choosing a material, the main thing you have to think about is the dimensions of the plumbing elements.
Characteristics that determine the size of pipes for water supply
Speaking of pipe sizes, they usually mean a combination of the following parameters.
- Outside Diameter - This is usually specified by the manufacturer.
- Internal diameter - is an important characteristic for parts of the plumbing system, measured in inches. For interconnected pipes and fittings, it should not differ.
- Nominal diameter (DN) - is a nominal value that is used when installing all parts of the water supply system. It is an average parameter, close in value to the diameter of the lumen.
- Product wall thickness.
- Length of the product.
Correspondence of pipe diameters
Quite often, a water supply system is a combined system that includes elements from different materials. Difficulties can arise here, since the diameter of steel structures is indicated in inches, and plastic products - in millimeters. In order to choose the right size, you can use specially designed tables. If you need to connect the steel part of the water pipe with plastic elements, then the table of correspondence between the diameters of steel and plastic products will help you.
1 inch corresponds to 25.4 millimeters.
Water supply capacity
The diameter of pipes for water supply has a direct relationship with such a concept as throughput. It is determined by the passage of a certain volume of water in a certain period of time. For example, a pipe with a clearance of 25 millimeters can pass through itself a volume of water reaching 30 liters in a minute.
The throughput is taken into account when calculating the dimensions of the parts of the plumbing system and the fluid pressure. It can be defined in three ways:
- Using formulas that use measurements of system parameters. Such calculations are quite complicated, so only specialists use them.
- Using tables for a specific type of material.
- With programs designed to optimize plumbing systems.
You need to know this: one of the advantages of plastic pipes, unlike steel or cast iron pipes, is the maintenance of a constant throughput value throughout the entire service life.
Choosing the diameter of plastic pipes
The optimal size of the elements of the plumbing system depends on many factors:
- the length of the water supply;
- number of connections and joints;
- the number of turns;
- number of water intake points;
- water pressure in a particular system.
The good news for non-professionals installing their own plumbing is the ability to abandon complex calculations and use standard solutions.
As a determining parameter, you can take the length of the plumbing system:
- for systems having a length not exceeding 10 m, pipes with a clearance of 20 mm are more often used;
- for 10-30-meter systems, products of 25 mm diameter are usually taken;
- lengths over 30 meters require the use of a 32 mm diameter.
If we are talking about intra-apartment wiring, then everything is much simpler. Since the water supply in the apartment has a short length, in most cases products with the following internal diameters are suitable here:
- 15 mm or half an inch;
- 10 mm or 3/8 inch.
For the riser choose the following dimensions:
- 20mm or 3/4";
- 25 mm or 1 inch.
A larger diameter may be needed in the following cases:
- If the water supply system has a complex structure, which has a large number of turns, joints and is characterized by pressure volatility;
- If water is constantly used in large quantities.
What threatens the wrong size of pipes?
If the installed plumbing components are of the wrong diameter, this can cause the following problems:
- Increased pressure in the system will create an additional load, leading to accelerated wear and an increase in the likelihood of breakthroughs and breakages.
- The water in the pipes will make noise - the buzz is also caused by the pressure being injected.
- A significant decrease in pressure when water is taken at one of the points - for example, when you turn on the shower in the bathroom, the water from the tap in the kitchen will flow in a thin stream.
