Heat-resistant putty for stoves and fireplaces
Many private houses and cottages have either heating stoves or working wood-burning fireplaces. Like all other designs, they need decoration.
Moreover, in one that is not afraid of a strong increase and a sharp change in surface temperature. Heat-resistant putty for furnaces fully meets these requirements, we will tell you more about it.
The content of the article
Why putty furnaces
There are at least two reasons why stoves and fireplaces need putty:
- Improving the appearance. No matter what material the stove is made of, it needs decorative finishes, and leveling the masonry with putty is one of the common options. Subsequently, a flat surface can be whitened, painted with heat-resistant paint or veneered.
- Safety of operation of the outbreak. Over time, cracks can appear in the masonry, and even in the brick itself, under the influence of high temperatures, through which smoke will escape.
Traces of soot on the walls are not the most unpleasant in this situation, the influence of carbon monoxide on human health is much more dangerous. Therefore, the instruction requires strengthening the structure with plaster or coating with special compounds.
Previously, stoves were coated with clay solutions, many owners of stoves (seeFurnace lining: material selection) in villages and villages use them to this day. But to prepare a mixture that will stay on a hot surface without crumbling and not cracking is not so simple.
To do this, you need to be able to determine the quality and fat content of clay in order to accurately calculate the proportions of the components included in the solution - sand, lime, etc.
It is much easier and more reliable to use mixtures that are available in ready-made form or simply diluted with water. Heat-resistant putty is produced by many manufacturers of building mixtures, it is characterized by different resistance to high temperatures, so choosing the right one is easy.
Material Features
Most heat-resistant mixtures are universal: they can not only be putty on the hearth to obtain a flat surface, but also perform starting plaster, use for masonry or tiling.
Note. When choosing a composition, it is first of all necessary to pay attention to its working temperature regime and correlate it with the degree of heating of the structure being trimmed.
Structure
The raw materials for the production of heat-resistant putties are clay, cement, sand, lime and gypsum. The main ones are lime and clay, they are used in all mixtures, other components may be absent or present in different proportions.
The compositions are:
- Gypsum-gypsum;
- Clay cement;
- Lime-clay, etc.
For reference. Previously, asbestos was often added to them, now this is not done due to the high toxicity of the material and its harm to health.
The choice of the mixture is largely determined by the location of the source. For example, if it is a street fireplace, the heat-resistant putty should not contain gypsum for its decoration - it is very susceptible to moisture.
Advantages and disadvantages
If you think that it is enough to take an ordinary cement putty so that the fireplace looks and works normally for a long time, then you are mistaken.
This is only possible for decorative foci that do not work for heating. And compositions for operating furnaces must have special properties.
If we talk about special heat-resistant putties, then they have the following positive characteristics:
- Ecologically safe composition of components. This is very important, since with strong heating, many substances that are harmless in the normal state decompose with the formation of toxins. There are no such substances in putty for furnaces.
- High strength and resistance to significant temperature fluctuations, low risk of cracking.
- Durability. Putty properly prepared and applied to the surface of the hearth will last at least 50 years.
- High adhesive ability, adhesion to bases of different materials.
For reference. Some types of kiln putty can even be applied to metal surfaces.
The disadvantages include a higher price than conventional formulations and the inability to use as a finish - the surface after putty must be painted or tiled.
Self-preparation of the solution and application
If you bought a ready-made putty or a special coating in a plastic bucket, you just have to mix it well before work. The dry mixture is shut with water on the recommendation of the manufacturer.
Note. It has a certain shelf life and may lose plasticity over time. Take this into account, prepare the amount of solution that you will definitely have time to use.
For self-preparation of putty, you need ordinary greasy or chamotte clay, sand and lime. The amount of sand per clay part depends on its fat content.
Without sufficient experience, it is very difficult to determine the proportions, so either consult with a competent specialist stove-maker, or still use ready-made mixtures.
If you already have experience with plaster or DIY putties, you can easily cope with the decoration of the fireplace or stove - the technology is the same, the tools used are standard. It is only important to remember that any putty, including heat-resistant, does not fit well on an unprepared surface. Therefore, before starting work, it must be cleaned of excess masonry mortar, grease stains, old paint, dust, and other contaminants.
Heat-resistant mixtures usually have good adhesion, but to improve the adhesion it is still desirable to treat the surface with a primer.
Conclusion
As always, to get more detailed information on the topic, we suggest you watch the video in this article. And when choosing a putty or plaster with heat-resistant properties, we advise you to consult with specialists and get acquainted with the reviews of those who already had the opportunity to verify its quality.
