Which is better: metal-plastic or propylene for water supply?

It is not always possible to say unequivocally which is better - metal-plastic or polypropylene, since each material has its own pros and cons. In general, metal-plastic is more reliable, but costs significantly more. A visual comparison of the advantages and disadvantages can be seen below.

Comparison table

When choosing metal plastic or polypropylene for water supply, it is initially recommended to study the technical characteristics of each material. A visual comparison of the most important parameters is presented in the table.

*only for a short time

Metal-plastic: advantages and disadvantages

In order to understand in detail what is better – metal-plastic or polypropylene, you also need to take into account the features of the products, their real advantages and disadvantages. So, metal-plastic, in fact, is also polypropylene. But unlike it, it is reinforced with a special aluminum layer, sewn with the rest with special glue, as shown in the diagram.

Thanks to the aluminum insert, such a pipe acquires several important advantages:

1. Strong thermal expansion during heating is compensated, and the risk of deformation is reduced. In this regard, it is easy to understand which is better – polypropylene or metal-plastic pipes. The latter option is more practical, since it can withstand even high temperatures up to +95°C - almost boiling water.
2. A diffusion barrier is formed that prevents oxygen from penetrating into the heating circuit. As a result, the service life of both pipes and radiators increases - they suffer less from corrosion.
3. The appearance of stray currents is excluded. But in this sense, there is no difference between metal-plastic pipes or polypropylene pipes. Both types of products have this advantage.
4. The internal surfaces are 100% smooth, which eliminates the accumulation of clogging. When considering which is better – metal-plastic or polypropylene for heating, based on this criterion, you can again choose both options.
5. Since the material is multi-layered, it ensures silent operation. The flow of water is practically inaudible, even if there is a fairly powerful flow.
6. If you choose metal plastic or polypropylene purely based on price, you should keep in mind that the first option is much more expensive. On the other hand, it is also more durable.

When studying which pipes are better - polypropylene or metal-plastic, you should not forget the disadvantages of metal. In fact, it has its disadvantages, some of which can be quite noticeable:

1. It is impossible to operate such pipes at subzero temperatures, because under these conditions the material quickly deteriorates and an emergency situation is possible.
2. If you use a threaded connection, the cross-sectional area decreases - accordingly, the volume of passing water per unit time also decreases.
3. When assessing which is better – metal-plastic or polypropylene for plumbing, you need to take into account that the polymer is poorly affected by direct sunlight. On the other hand, this drawback is inherent in both materials.
4. In rare cases, even metal-plastic can become deformed due to temperature effects. But this minus can be easily compensated for by tightening the fittings.

Polypropylene: types, advantages and disadvantages

If you choose metal-plastic pipes or polypropylene pipes for water supply, you need to study the features of each material. Unlike metal, polypropylene is a monolithic pipe. It does not have layers as such, but sometimes the product is reinforced with foil, which is directly soldered into the plastic.

If you consider plastic or metal-plastic for water supply, you will also need to study the types of pipes. The main classification is related to the conditions under which pipes can be used, that is, how much they can withstand certain temperatures and pressures. Depending on this, they are assigned the appropriate marking:

1. PN10 – operate at a pressure within 1 MPa, intended only for supplying cold water or for heated floors. A comparison of metal-plastic and polypropylene pipes shows that this option has limited use.
2. PN16 – operating pressure limitation up to 1.6 MPa. Such pipes can be used to supply cold water, as well as hot, but with a temperature limit of up to +60°C. In this regard, it is clear whether to install plastic pipes or metal-plastic ones. Metal is more practical because it can even withstand boiling water.
3. PN20 – can cope with pressure within 2 MPa. At the same time, they are more resistant to hot water - the upper limit is +80°C.Therefore, such products can also be used for both cold liquid and coolant when supplied to batteries.
4. P25 – operate at pressure within 2.5 MPa. The most resistant type of pipes, as it is designed for temperatures up to +95°C. The reason is that these pipes have an aluminum layer that is located closer to the outer surface. In this case, there is no doubt that metal-plastic or polypropylene is more reliable: products made from both are quite durable.

When studying which is better for heating – metal plastic or polypropylene, it is advisable to consider the positive and negative characteristics of the latter. The obvious advantages include the following:

1. Durability, minimal risk of corrosion.
2. Resistance to pressure changes and mechanical stress - metal plastic or polypropylene in this sense are approximately the same.
3. The smooth surface on the inside prevents clogging. According to this criterion, there is also no difference between what is better – propylene or metal-plastic.
4. Even if the water flows intensively (for example, an apartment on the lower floor), the noise is practically inaudible.
5. The joints are completely sealed, preventing leaks (provided they are installed correctly).
6. Low thermal conductivity – insignificant heat loss.
7. If necessary, you can perform hidden installation.
8. The material is hard, but even if deformation occurs, it is quite repairable.

But if you carefully study which is better - metal plastic or polypropylene for water supply, you cannot help but mention the disadvantages of the latter:

1. Not all types of pipes can withstand high temperatures close to +100°C.
2. Installation is quite complicated, although in the case of metal-plastic it is even less convenient due to the less flexibility of the pipes.
3. The material is flammable.
4. All polymers are sensitive to sunlight.

From this review it is clear which is better – metal-plastic or polypropylene for water supply. We can say that both materials are quite good and durable. But metal-plastic still benefits due to the reinforcing layer of aluminum. Although it costs more, the investment will pay off due to its long service life.