How to paint cast iron batteries in an apartment

How to paint cast iron batteries in an apartment How and how to properly paint cast iron batteries

Before choosing the methods and ways in which it is supposed to paint cast-iron heating batteries, you need to decide for yourself what is more important - to ensure the durability, reliability of a metal radiator or to achieve an aesthetic visual design, which, in general, is important given the fact that that batteries and radiators made of cast iron, even new ones, are far from the nicest.

So, let's look at how to paint cast iron batteries.

Is it possible to paint cast iron batteries

It is believed that each new paint and varnish layer on the radiator heating surface will reduce its degree of efficiency by an average of 15%. After applying paint in four layers, cast iron radiators will heat up 2 times worse than new ones.

For this reason, the desire to paint cast-iron radiators in an apartment 5-10 times before the start of the heating season should be restrained by meaning.

Why do you need to perform useless work, maybe you should still replace the radiators with your own hands or entrust the repair work to specialists?

It makes sense to try to paint the cast-iron housings of the radiators with your own hands only in two situations:

  • After installing a new heating radiator, painting is required without fail, because, most likely, batteries with primed surfaces are sold in a hardware store.
  • After overhaul of radiators, including elimination of leaks, replacement of registers, as well as removal of fistulas or depressurization on fixing.

In any case, there is a chance not only to protect the body and its surface from rust, but also to paint beautifully heating batteries, especially cast iron ones, which require special attention and care. You also need to choose the appropriate paint, select the method of applying paint and varnish material, the most suitable for home conditions. And the last point will always remain a stumbling block, and if the registers are in the garage or basement, disassembled, then it is better to paint cast-iron heating radiators with powder paint.

She looks better and the quality of the coating is much higher. But in order to paint, it will be necessary to disassemble the radiator, immerse it and take it to the nearest paint shops in the car service.

Professional painters will definitely suggest the best paints and varnishes for painting cast iron radiators. Perhaps it will be a polyester primer or a simple material for painting brake blocks and discs. Naturally, painting from the pros will be extremely expensive, but if you do everything right, then you can forget about it for 30 years, that the cast-iron body needs to be painted at all.

But most often it will not be possible to solve the problem with the described method, usually by technical parameters, and therefore it will be necessary to look for a method for staining cast iron batteries in an apartment.At the same time, try not to poison yourself with a toxic solvent and at the same time provide a beautiful appearance to the radiators.


Which paint is suitable

So, first you need to decide which paint you can paint the cast iron body with. It is not difficult to do this, the assortment is small, and 3-4 main types of paints and varnishes are usually used for heating radiators:

If you have the opportunity, you can buy hammer paint. If you apply it according to all the rules, then after drying, the layer will come out with a shine and the surface will be as if chased. The strength of coatings with a hammer mixture is much higher than that of conventional acrylic or alkyd materials, however, the layer thickness will be much greater. Accordingly, the consumption of material for cast iron radiators, even if painted with a spray, will increase by 55%.

Please note that this treatment reliably protects the cast iron base from all mechanical damage, the effects of detergents and cleaning components, and scratches. But only clean and new batteries can be painted correctly, without traces of old paint and varnish materials.

The only negative is the ugly gray color of the batteries

Bronze and silver

If you don't know, than to paint cast-iron radiators, then one of the painting methods is to use paints and varnishes with a filler in the form of a powder of metal, usually bronze or aluminum. The metallic type of filler in the lacquer composition increases thermal conductivity, while titanium oxide, zinc, lead often impairs thermal transfer. Before applying the material, the surface is not primed, but cleaned to a metallic sheen, and ideally, it is required to process everything with a passivating compound.

Before painting cast-iron heating radiators with your own hands, the metal must be wiped off with a rag soaked in acetone or solvent No. 646.

Pentaphthalic and alkyd paints

One of the most difficult paints, and it is possible to paint a cast-iron body, but only for 4-5 years of service. The paint and varnish material is viscous, and a lot of solvent needs to be added, since otherwise it will be extremely difficult for a cast-iron radiator inside the registers. They give a very thick coating, even when the surface is painted once.

For this reason, if you decide to paint radiators with alkyd enamels, it is better to choose special compositions and paint in 1 layer. On sale there are special acrylic water-dispersion paints, which give a beautiful coating, if you need to paint cast-iron heating radiators, and then you should choose acrylic heat-resistant enamels.Water-dispersive materials are considered good for register processing, but it is better not to use it for cast iron radiators. Water-based emulsions do not protect metals well, and often turn yellow and become covered with dust during intense heating.

What cannot be used to paint cast-iron radiators

In addition to the options that are listed, there are at least a couple more varieties of paints and varnishes, which simply make no sense to paint cast iron.

Radiators should not be painted with latex and polyurethane paints, they give a thick layer, which will increase the thermal resistance and worsen the heat output. Moreover, the materials age quickly and become cracked. Oil paints have approximately the same properties. During the first 2-3 years after painting, the layer of material on the cast-iron radiator will look perfect, but the battery will heat up extremely badly.

Preparing cast iron batteries for painting

Many mistakes that are made when trying to paint cast iron radiators are related to illiterate surface preparation.

Painting steel surfaces and cast iron are two differences, and quite large, because the material lies flat on the steel, and also provides good adhesion. For cast iron, everything is more difficult, because it will be necessary not only to remove the old paint and varnish layer and primer, but also to clean the metal to a shine, and then degrease the surface with hot water in which the solvent and soda are dissolved.

You can remove old paints and varnishes using a brush attachment on an electric drill with bronze bristles, or try to use an industrial hair dryer and the same metal brush. It is impossible to use chemical washes or burning with a gas burner, because with strong overheating or the use of acid solutions, the intersection seal will first of all burn out.

Is the priming of cast iron batteries required before painting

If the radiator is new and covered with factory primer, then it is not necessary to remove the layer.

Most often, the quality of the coating with a primer in the factory is higher than that which can be obtained in an apartment. The only exception is preparation for nitro paint, and usually metals are brushed to a shine. This ensures excellent adhesion of the nitro paint to the cast iron surfaces of the batteries. In other cases, it is recommended to cover a clean or well-cleaned old radiator with a thin primer layer. To obtain excellent adhesion, the primer must be diluted 1 to 1 with P647 and rubbed into the surface with a damp cloth.

The primer layer will be very thin, almost colorless, but this will not affect its parameters. The paint material will begin to adhere just as well as on a thick layer and the heat resistance will be reduced by 35%.

How to paint cast iron batteries correctly

You can paint cast iron radiators efficiently or quickly.If it is required to perform work in the shortest possible time, then it is better to use a spray bottle or aerosol cans for painting wheel disks. One cast iron battery will take at least 2 simple cans, which is about 0.

25 kg of paint. The advantage of the method is a thin layer of paint and a high-quality layer of gloss. Moreover, it will be possible to paint even very hard-to-reach places, while carrying out the work in a maximum of 10 minutes. It is much easier to paint cast-iron products with a spray gun, but in an apartment or at home, using the device will create many problems, and therefore you should immediately abandon such technologies.

How to paint cast iron batteries in an apartment If there is a choice, then it is worth painting the batteries with a brush with stiff bristles, without a roller or other similar tools.

The inconvenience of using such a brush lies in the strong spraying of paint from the bristles, and it is required to take the material in small portions, and then rub it thoroughly on the cast iron surface. It is not very convenient to work with such a tool, but in any case, a brush with high rigidity makes it possible to paint the oldest cast-iron radiators in a house with high quality. Moreover, a small brush with short-cut stiff bristles is convenient for painting the interior of the recorders. If you try to do everything with a simple paint brush, then most of the paints and varnishes will simply flow to the floor.

Please note that the rigid base of the brush provides excellent air squeezing out from under the paint layer, and therefore, after drying, the paint layer will be without cavities, thin and without delamination.

How to make antique staining

To make a radiator look like an antique heater, you need to choose the textures and colors of paint correctly. For example, you can try to design a battery in the form of a product made of non-ferrous metals, copper or brass. This requires special special fillers that imitate a copper surface. you will need to paint at least 4-5 layers, with intermediate polishing of each. The result is a cast iron radiator that is very similar to the copper heat exchanger used for heating 150-200 years ago.

Ancient batteries were often equipped with decorative patterns, and the manufacturer's inscriptions were always made on the surface, stamps and other attributes of special production were put. All this can be reproduced by means of glued, cut foil. The decor will need to be glued to the cleaned cast iron surface using thermally stable adhesive compositions, for example, epoxy-type resin. After painting, cast iron batteries will look much like antique radiators.


Dyeing cast iron batteries is no more difficult than all other metal objects in the house.

The only condition that should be remembered is the use of additional protection for the joints and fastening points of nuts, threaded beads, plugs, through which the cast-iron radiator is fastened to the water heating system. the less you try to paint such places, the longer the heating system will last.