What solution is the chimney placed on?

Arranging the heating system of a private house involves certain difficulties with laying the chimney. The problem arises when using red ceramic bricks, which should only be laid using a special fireplace/stove mortar.

There are several types of compositions for laying a stove, and in each individual situation it is advisable to use only a specific type. The very use of the composition (its preparation) is quite possible with your own hands.

Mortar for laying brick pipes

When building a private home and installing a heating system, many homeowners are faced with the difficulty of laying a chimney. Quite often, red ceramic bricks are used for this work, which must be laid using a special oven mortar. We will talk about how to choose the composition used for laying the chimney in this article. Many homeowners mistakenly believe that for laying a chimney they can use ordinary cement mortar, which was used for laying brick walls. However, experts do not recommend using it when laying a stove and chimney. The fact is that during operation the chimney is subjected to significant thermal and chemical loads, and a conventional binder mixture cannot be used in this case. It is necessary to use special thermoeffective mixtures that can withstand increased thermal loads with equal ease and are resistant to various acids .
For laying the stove pipe, it is recommended to use compositions that are normal in terms of fat content, since they are characterized by proper plasticity and are not prone to cracks. For this work, complex compositions are used, consisting of several components. Binders based on sand, cement and lime are very popular. Also on sale you can find ready-made mixtures intended for bricklaying, characterized by excellent heat resistance.

The only drawback of such dry mixtures for masonry is that they are expensive. Therefore, many homeowners, when engaged in such construction work, prepare the solution themselves.

You should also pay attention to the density of the composition used. The prepared mixture should be homogeneous and vaguely resemble sour cream in structure. It should be slightly squeezed out when laying bricks, but should perfectly hold together the materials used. The following compounds are used for this work:

Clay.
Calcareous.
Cement with the addition of lime and chamotte.
Lime-gypsum.

Components and components of a chimney

Before starting construction, it is worth studying in detail the information about what components the chimney consists of. Many ordinary people mistakenly believe that such a structure is made only of brick. What does the smoke exhaust duct consist of?

It is based on the installation of a mounted pipe attached directly to the surface of the furnace. If desired, you can install a damper on it. It is necessary to lay such a pipe using the technique of tying the bricks after each laid row. Before approximately 4 rows overlap, you should stop laying out the base. The name of the place is the neck of the fluff. Next, the masonry expands from row to row upward.

It's time to install the chimney itself. Let's consider the main stages of construction.

The design drawing is reviewed. Typically a standard installation scheme is used. If you plan to install a gas boiler, then special metal pipes should also be laid in the base.
The size of the channel is determined, and according to the degree of patency of the pipes, it is selected individually. It is worth remembering that it also depends on the thickness of the joints in the brickwork.
As mentioned earlier, the device begins with laying out the top pipe. Adhere to all previously installed brick dressings.

Clay mortars for masonry

High-quality clay compositions with the addition of cement and sand were successfully used for chimney laying in the past, but today they are gradually being replaced by other, high-quality and

inexpensive preparations. The clay-based composition is resistant to high temperatures, but it can be destroyed when exposed to moisture. That is why it is necessary to install a large metal umbrella over the stove pipe, which will completely prevent water from getting inside the stove. When using clay mortar for laying a brick stove and chimney pipe, you must remember that using wet, fresh firewood as fuel in this case is not recommended. This will also lead to failure of the chimney.

To increase the strength indicators when preparing clay mortar, you can add about one hundred grams of table salt per kilogram of Portland cement. Just remember that salt must be mixed with water an hour before cooking. To check the quality of the prepared mortar for the brickwork of the chimney, it is necessary to mold a small ball with a diameter of about 50 millimeters from the resulting mass. The resulting ball should hold its shape perfectly and not stick to your hands. Subsequently, the laying of the chimney using a clay composition is carried out according to the standard scheme.

Important Construction Aspects

After completing all the previous steps, you should start laying out the cutting neck. For a standard chimney, a laying of just five bricks will be sufficient.

So, how to build correctly?

The beginning of the cutting itself. The parameters of the outer surface will be approximately 600x500 mm. You need to insert halves and quarters of a whole brick. You should first purchase special building plates that will be inserted inside. This will help to lay a smooth channel for removing smoke.
Construction of the third row. Dimensions will be approximately 650x550 mm. It is worth choosing denser plates of approximately 80 mm here. At this stage, the fluff will gradually begin to take on its final shape.
Layout of the fourth and fifth rows. A whole brick is used. The sixth row is laid out with obligatory dressing and nothing else.

Attic work

For attic work, you should start by arranging the main riser. You need to make a hole in the roof surface and pass equipment through it. This is all the work done in the attic. Next, the part through which the chimney is led to the roof is arranged.

Roof

As before, the primary stage of work is laying out the riser. We should not forget about the brickwork connections. The pipe is installed approximately three rows above the roof level, then you can begin to lay the otter.

Otter

This stage is required to be laid out in nine or more rows. Each subsequent one is larger than the previous one by a quarter of the whole brick. must be strictly adhered to - it should neither expand nor narrow. The protrusion will face forward. The edges of the chimney remain in place. By pushing the bricks forward, the otter will expand in width approximately in the third setting. In the fourth row, the protrusions on the sides should become longer. The fifth row should close the gap between the roof and the built-up chimney masonry.

The sixth row will close the resulting side open zones. The formation of the main protrusions will be completed on the seventh laying. All that remains is the design of the rear part.

The last, fourth protrusion should form in row number eight. To form the correct chimney, you must carefully follow the established dressings and not disturb the order of the plates. The ninth clutch is identical to the eighth. At this stage, you can begin laying out the so-called neck of the chimney.

This is also done in several rows. To be more precise, in three or more rows. The size should be selected based on the original dimensions and height of the smoke channel. In no case should you violate the rules for arranging a chimney above the roof of a building, since the future performance and even safety of the device depends on this. The established dimensions are saved regardless of the selected device model.

Final stage

The construction of the chimney with your own hands is almost complete. Now you need to build the head. You can start laying it on the formed neck. The stage is performed exactly the same as fluffing, so it shouldn’t be too difficult. When the work is finished, you should take a little time to select a weather vane or a cap for the chimney.

Lime mortar for stove pipe

Lime mortars for laying stove pipes began to be used relatively recently and today they have become the main masonry material. When properly prepared, it provides excellent heat resistance, is not affected by moisture and holds the masonry together efficiently, ensuring maximum durability of the entire structure. To improve the quality of lime mortar, it is recommended to use slaked lime, sand, a small amount of cement and gypsum. The classic recipe for brickwork involves one mass fraction of lime and five parts sand. Lime and cement are added in minimal volumetric quantities. You also need to add water and stir everything until smooth. The solution should have the consistency of thick sour cream and not stick to the trowel and concrete mixer.

When using such a solution intended for laying a stove pipe, you should remember that its quality directly depends on the quality of the lime.

That is why it is recommended to use boiling lime, which is filled with water and then left until it is completely quenched. It is best to carry out the lime slaking procedure in plastic barrels or pre-dug holes lined with boards. Only after this can you begin to prepare the composition necessary for brickwork.

Materials and tools

So, what do we need to mix a good solution? First, the tools. With their help, we will knead, sow, lay... Secondly, we need the materials themselves, that is, what we will knead, sow and lay.

Tools: a shovel - for preparing sand and clay, a trowel - mix and use for work, a sieve with a mesh size of 1-2 mm, container (trough, bathtub, tank), a couple of basins, a bucket, a drill or a hammer drill with a mixer attachment.

Necessary materials: clay - the base of the solution, sand - the main filler, cement - the binding component, lime , asbestos , gypsum - auxiliary and additional components (usually not used), clean water .

Cement based mortar

Cement-based mortar is characterized by increased strength and ease of preparation. Cement-based brickwork is strong, durable and resistant to soot and other aggressive substances. Today, cement-based masonry mortar, due to the affordable cost of the components used and ease of preparation, is most widespread.

The composition for the chimney above the roof is made of cement, sand and the addition of water. The ratio of cement and sand can vary from one to one to one to six. It should be remembered that such a solution sets quickly, and an hour after preparation it begins to lose its strength and elasticity. Therefore, you should not prepare it in large batches, but use it immediately after preparation within 30 – 60 minutes.

How to prepare mortar for laying stoves? Composition and proportions of ingredients

I am glad to welcome you, dear reader!
Today we’ll talk about how to prepare the right clay solution for a stove or fireplace. Those who have dealt with the laying of a brick structure are well aware of the procedure for preparing the mortar, which should be prepared not anyhow, but according to all the rules of stove art. A real stove maker can immediately determine whether a mortar for laying stoves is good or bad. To do this, the master just needs to rub it between his fingers.

But it is difficult for a beginner to understand this “competent issue”. And he gets the impression that “brick glue” can be prepared by mixing clay, sand and cement. All this is true, but... The solution for the oven must be prepared correctly.

From this article you will learn:

High-quality preparation of cement mortar

We pour the used cement and sand through a sieve to completely get rid of lumps. Mix sand and cement until a homogeneous mass is obtained. At the final stage of cooking, add water to obtain the desired consistency. Just remember that such a solution based on cement and sand alone does not have proper heat resistance, so it is not recommended to use it for laying a chimney in the immediate vicinity of the stove.

If you need to prepare a heat-resistant solution, then you will need slaked lime, which is diluted with sand in a one-to-one ratio. Next, 0.5 parts of cement are added and everything is thoroughly mixed. A properly prepared solution of lime and cement has excellent thermal stability, which allows it to be used for laying the lower part of a brick pipe. Also, to increase the strength of the material, fireclay can be used, which improves the thermal strength of the composition.

When using cement to prepare mortar, it is recommended to use a material with a strength index of at least M400. This will ensure the necessary strength of the brickwork and its durability. The thickness of the seam can vary from five to ten millimeters.

Foundation mortar

The first stage of laying a stove is creating a foundation for it. It is recommended to use concrete mortar used for the foundation to make the lower surface of the combustion chamber. For it connect:

Cement grade M300 or M400. One part of the total volume is taken. It makes no sense to take higher quality brands of cement - their high cost here is unjustified, 300 or 400 is quite enough.
Gravel or crushed stone. This component requires 2 parts; It is advisable to take small-fraction varieties.
Fine sand, also double the amount. Before use, it is necessary to sift it.
Fireclay powder (fireproof product). Depending on the resulting consistency, the volume of this component ranges from 0.3 to 0.5 parts.

A simpler composition is cement, gravel and sand in a ratio of 1:3:3. The mixture is diluted with water in such an amount that a mass is obtained, the thickness of which resembles sour cream. Checking the correct consistency is simple: the finished solution must remain mobile and plastic, but spontaneous drainage from the blade of a shovel tilted at 45 degrees is not allowed.

Lime-gypsum mortar

Inexpensive to produce, lime gypsum mortar is actively used in finishing and plastering stoves. When cement and a large amount of lime are added to it, this composition can easily be used for laying a brick chimney pipe. The advantage of using it is the ease of working with it and faster setting. You just need to correctly calculate the ratio of components and achieve the desired consistency of the prepared mass.

Before firing the stove for the first time, you need to thoroughly dry the masonry, which will eliminate the danger of cracking the chimney.

Cleaning from impurities

For the stove solution you need clean sand. To separate it from impurities, it must first be sifted and then washed. For sifting, a fine mesh sieve with a mesh size of 1.5 mm is used. Next, the sand is washed as follows: a sack with sagging is pulled onto the holder (you should get a kind of net), into which the sand mixture is placed. The structure is fixed on a stand, sand is poured in and it is washed using a hose and a stream of water. The process continues until the water flowing from the sand becomes clean.

The clay is mixed with water and left to soak.

To remove foreign impurities from the clay, it is washed. Grind, place in the upper part of an oblong container (for example, an old trough or bathtub). The container is installed at an angle of 4–8°. Water is poured into the lower part so that it is at the top and does not touch the clay. Use a small spatula or iron scoop to wash the clay. Gradually it softens and a homogeneous paste-like substance forms at the bottom, which is carefully transferred to another container. The process is continued until the required amount of solution is obtained.

Sand is sifted through a fine mesh sieve

If you purchased packaged dry clay, you need to soak it. The process of saturating clay with water is quite simple. To work, take a wide and deep container, fill it with dry clay to a level of 10–20 cm, level it and add water. The amount of water is so that everything is completely covered. After a day, mix thoroughly with a shovel, add liquid if necessary and leave again for the same period. When everything turns into a paste, the clay is ready. This is repeated several times until all the required amount is soaked.

Compositions for stove masonry

One of the features of furnaces is the big difference in the operating conditions of its parts. So, a brick pipe inside a building is exposed to hot air - smoke, condensation, and some acids formed during fuel combustion. Over time, soot and soot settle on the walls, which contributes to even greater accumulation of condensate and a decrease in draft, and so on. However, no destructive forces act on the pipe walls from the outside.

The chimney above the roof, in addition to all of the above, becomes a victim of weather factors: wind, rain, snow, and, most importantly, temperature. The difference between the temperature of the exhaust gas and the air temperature can reach hundreds of degrees. Not every material can withstand such an impact.

Mixture with lime

To build the foundation of the stove and build a chimney over the roof, compositions with lime are used. You will need water, sand and lime paste. To increase strength, cement is added to it, and gypsum is added to reduce the setting time, but it is usually poured only for plastering work.

The quality depends entirely on the lime paste. Pour enough water into powdered or lump lime so that it cannot boil. The dough preparation process lasts almost half a month. All this time it should be covered with a small amount of water. The prepared lime should be stored for a month before using it to mix the solution.

Instructions for making lime composition:

1. The dough and sand are passed through a sieve. If the dough is too thick, then water is added to it.

2. Sand is poured into the lime and everything is thoroughly mixed until smooth.

3. The proportion of sand depends on the quality of the lime and can be from 0.5 to 5 parts.

Average plasticity is considered optimal. This can be determined as follows: a couple of minutes after cooking, a wooden spatula is lowered into the composition. If after pulling it out there is nothing left on it, it means that the solution is not flexible enough. If the thickness of the dough is about 2 mm, then it is of medium plasticity and should be used as a baking dough.

Mix with cement

The cement composition is the most durable. It is used for laying foundations in places with high humidity and for finishing pipes above the roof of a building. Thanks to the cement, it sets quickly, but that is why it must be used within an hour. After this time, it begins to harden and strength decreases. It includes water, sand and cement, the proportions of the components depend on the brand of cement.

Guidelines for preparing cement mortar:

Review of ready-made mixtures and their cost

There is absolutely no need to spend time sifting bulk materials and dividing them into portions, since you can purchase ready-made products for laying a furnace and mix it according to the attached instructions.

1. Each solution has a maximum possible temperature of use (this characteristic is also called heat resistance), it depends on the composition. For example, Ogneuporsnabservice can withstand heating up to +850 °C, and fireproof from the same manufacturer - +1300 °C. The first oven mixture consists of red clay, sand and plasticizer, and the second – of refractory clay and quartz sand. For the firebox it is better to use a fireproof version, but for the exterior of the stove a simple one is enough.

2. The Plitonit company also produces compositions for the construction and finishing of stoves and fireplaces. But unlike the previous manufacturer, it produces powders in different shades, for example, gray and red.

3. The solution from the Terracotta company is somewhat different, but, like that of Ogneuporsnabservis, it can withstand high temperatures - up to +1300 °C. It includes kaolin clay, fireclay and sand. But the time during which it must be consumed is 3 times less than that of previous mixtures - only 1 hour.

4. When choosing a composition, you need to pay attention to what type of brick it can be used with. For example, the Finnish Weber Vetonit ML Tuli should only be used for laying fire-resistant bricks.

When buying a dry composition at any cost, you should keep in mind that you need to knead it using a mixer and not by hand.

The finished clay mortar can be stored for months, and the lime mortar can be stored for several days. Containers with them must be kept closed and in a dark place. Only clean water is used, without algae or other debris. All components must always be sifted.

Author: Ivan Yaskevich

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Types of stove building mixtures

The solution consists of some kind of binder, filler and solvent.

The first component performs the main task - when hardened, it forms a strong connection that holds the masonry elements. The filler is necessary to reduce shrinkage, since during the transition from a viscous to a solid state, the volume of the substance decreases. The filler retains the primary volume and prevents the resulting compound from crumbling.
The solvent in the vast majority of cases is water. It evaporates when solidified without forming any additional compounds.

In the simplest case, the mixture consists of one binder and one type of filler. In mixed versions, the composition is much more complex.

According to their purpose, mixtures are divided into 3 groups:

masonry - that is, used in laying the stove itself, foundation, chimney, and so on;
finishing - used when lining the stove with bricks or tiles;

To construct brick pipes, masonry mortars are used. They are divided according to the nature of the binder component:

limestone - slaked lime serves as a binder. This styling mixture requires the use of tools;
cement - the base is cement or Portland cement;
gypsum - not used for the construction of a chimney;
mixed - that is, including several binder components: lime-cement, lime-slag, and so on.

To construct part of the pipe under the roof, you can use solutions based on clay, cement or a mixture of clay and sand. For the part above the roof - lime, cement or cement-lime, since here one of the main requirements is greater water resistance, and the clay composition is washed away.

Additives for clay mortar

If you use a refractory material in the mixture, then only clay and sand go into the solution. But such a component is not always available. Often you have to use ordinary clay or even loam. If the strength of the mixture seems unsatisfactory to you, the solution must be supplemented with strengthening additives. As such, either kitchen salt is used in the amount of 100 g per 10 kg of clay component, or Portland cement at the rate of 1 kg per the same amount of clay. The plasticity of the composition must be double-checked as described above.

How to prepare clay mixtures for stove masonry

The mixture is used for construction inside the building. It cannot be used for chimneys on the roof. The optimal proportions are considered to be: the ratio of the shares of clay and sand as 1:1 or 1:2, and the volume of water as 1:4. In practice, everything is determined by the fat content of the clay.

One of the tests is used to check raw materials. For example: a kind of dough is kneaded from 500 g of clay and balls with a radius of 20–25 mm are rolled. The ball is placed between two dies and squeezed until cracks appear on the lump of clay. A ball of thin clay falls apart even with slight pressure. From poor - when the volume is reduced by ¼ or 1/5. Normal cracks appear when reduced to 1/3 of the diameter, and oily – when reduced to ½.

The best is normal clay. When using it there is no need to add sand. If it is oily, then carefully sifted river sand is added in a proportion of 0.5 to 5 volume fractions. The result will be checked using the test described above. If it’s poor, they wash it out: fill it with water and wash out the excess sand.

To obtain the solution with your own hands, take the following steps.

The clay is laid on a flooring made of boards measuring 1.5 * 1.5 m. It must be applied in layers and moistened with water.
If you need to add sand, it is laid in a layer on top of the moistened clay.
As soon as the clay gets wet, it is mixed and raked into a ridge about 30 cm high. Then the ridge is chopped with the edge of a shovel into plates, the edges and lumps are crushed. Then they are collected again into a ridge.
Stirring is repeated 3–5 times until there are no clots left in the resulting mixture. The finished solution slides off the iron shovel, but does not spread. A sample can be seen in the presented photo.

How to prepare a lime mixture for a chimney

Lime mortar is required for roof structures. Its components are sand, water and lime paste. The latter is prepared by slaking lime.

The preparation method depends on the quality of the lime. If quick-quenching lime is used, then pour water into a special container - a slaking box - 1/2 the height, and then add lime. When steam forms, stir vigorously, and after quenching is completed, strain through a sieve with mesh sizes of 5 * 5 mm.
The medium-extinguishing one is poured into the box at 1/4 height and filled halfway with water, and stirred when steam appears. Water is added in small doses until the mixture is completely extinguished.
Slow-extinguishing is poured into the box at 1/4 height and moistened with water. After cracks appear, mixing begins with the gradual addition of water in small portions until the consistency of the mixture reaches the state of lime milk.
The substance is poured into creative pits, where it is stored under a 50 cm layer of earth. It is recommended to keep the substance for about a month before use.
The resulting lime dough is filtered with your own hands through a sieve with smaller cells - 3 * 3 mm, and mixed with sand. If necessary, dilute with water.

The finished composition should be held on a wooden paddle with a layer of 2–3 mm.

The video examines in detail the process of making mixtures for chimneys on the roof.

Checking the clay before preparing the solution

If the solution has normal fat content, the trowel is removed from the batch clean or almost clean.

To properly prepare a clay solution, you need to test the clay: add a little water to half a kilogram and knead it well with your hands until it completely absorbs the water and begins to stick to your hands. Having made a stiff dough, they form a ball with a diameter of 40-50 mm, and from another similar ball they flatten a cake with a diameter of 100 mm and dry both products for 2-3 days. If during this time cracks form on the cake or on the ball, it means that the clay is too greasy and you need to add sand to it. And if there are no cracks on the ball and cake after drying and they can withstand a fall from a height of 1 m, it means that the clay can be used in preparing a solution. Skinny clays do not crack, but they are not strong, so they need to be mixed with fatter clays. Clay or sand is added in several stages until the solution is ready.

To prepare the solution, use different clays, mixing them dry and then mixing them with water. Add 0.5-5 parts volume of sand to the fatty clay. It must be sifted through a fine sieve with 1.5×1.5 mm holes. Very thin clay is washed out - excess sand is removed from it by washing with water.

Instructions for stove mortars (for laying chimneys): what are they and how to prepare them?

Ready-made formulations

If you do not want to prepare solutions yourself, select proportions and check mixtures for suitability, you can use ready-made dry compositions. Professionals especially recommend mixtures that include clay with good fire-resistant characteristics, cement and specially treated sand - for example, Vetonit TM. “TeploKlad” performed very well. It is based on fire-resistant cement, a number of additives that increase the plasticity of the solution, and a filler that increases the heat resistance of the composition. You can also take a closer look at other mixtures produced using clay and fireclay sand, based on kaolin clay and others. Rules for diluting mixtures are necessarily provided by the manufacturer and do not cause problems. The main disadvantage of ready-made compositions is the high cost of laying the furnace. The consumption of dry mixtures is quite high, and their cost in the full required volume is quite high. This is why most stove makers prefer solutions that they prepare with their own hands.

Why is it so important to choose the right mortar for laying a chimney?

The problem with fireplaces and stoves is that each segment of such a system is exposed to different negative effects (or with different intensity). The brick pipe inside the room “gets” the most – it is affected by smoke, condensate (moisture) and various acids formed during fuel combustion.

The process of laying cement-based kiln mortar

As a result, over time, large quantities of soot and soot begin to settle on the walls of the chimney pipe, which ultimately results in even more condensation and a decrease in draft. In this case, the outer part of the chimney does not suffer at all - it is not affected by any aggressive factors.

The chimney segment above the roof suffers from several other problems. The whole problem there is precipitation, specifically wind, rain and snow. But an even bigger problem is the difference between the temperature of the exhaust gases and the temperature of the air masses.

That’s why you need to choose the right solution for laying the chimney in order to protect it from the listed negative factors (it is simply impossible to completely avoid their impact ).

Chimney cleaning

A layer of soot settling inside the chimney not only reduces its cross-section, but also increases the likelihood of a fire, since it can ignite. Sometimes it is even specially burned, but this method of cleaning is very dangerous. It is more correct to remove soot using a combination of two methods:

Mechanical involves the use of brushes and scrapers on long, extendable holders, as well as weights on a strong cord, which are passed into the chimney from above.
Chemical: a special product is burned in the firebox along with regular fuel, for example, “Log-chimney sweeper” (sold in hardware stores). It contains many substances - coal wax, ammonium sulfate, zinc chloride, etc. The gas released when this product burns forms a coating on the walls of the chimney that does not allow soot to subsequently stick to them.

The second method is used as a preventive measure.

"Log-chimney sweep" will clean the chimney in two weeks

Types of solutions

All types of chimney mortars consist of binders, filler and solvent. The first two components work in “close interaction”:

The binder, after hardening, creates a strong connection, which ultimately holds all the elements of the masonry. And the filler, in turn, is intended to reduce shrinkage, because during the transition from a viscous to a solid state, the volume of the substance always decreases significantly. It is the reduction in the volume of the substance that the filler prevents.
Typically, water is used as a solvent, which after hardening does not form any auxiliary compounds.

Determining the quality of clay

The main indicator is fat content. There are fatty and lean clays. When the first one dries, it significantly decreases in volume and cracks, while the second one crumbles.

Clay can be fatty or skinny

Let us immediately note that there is no strictly defined ratio of sand and clay to obtain a good solution. Proportions are determined experimentally, by selection depending on the fat content of the rock.

The fat content of clay rock can be determined in the following way. Roll out ropes of clay, taking a thickness of 10–15 mm and a length of 15–20 cm. Wrap them in a wooden mold with a diameter of 50 mm. If the clay is oily, then the rope stretches gradually, without cracks appearing. Normal ensures smooth stretching of the bundle and breaks, reaching a thickness of 15–20% of the original diameter.

Mortar for brick chimney, proportions

Brick chimney mortar

Nowadays, thanks to the Internet, you can find almost any information. Lots of videos on various topics.

As a result, more and more people prefer to do things with their own hands. For example, if earlier stove-makers had to be hired to lay a stove, now many people lay out the stove themselves.

Fortunately, you can view the entire process step by step on the Internet. And special “smart” programs will make accurate calculations of the brick and build a 3D model of the stove.

However, it is one thing to understand the order of laying bricks, and quite another to know the exact proportions of the mortar for laying a particular section of the furnace.

After all, you want an object created with your own hands to be functional, strong, and durable.

Preparation of stove solutions: types, applications, recipes

When performing furnace work, different solutions are prepared for different purposes:

For these purposes, solutions are used:

The stoves are placed on clay mortar , adding a little salt or cement for strength. Many people use only clay with water, without additives. To make mixing the mortar easier, some stove makers make wooden flooring from boards with low sides. The wide working mixing area allows for better preparation of the solution.

The stoves are placed on a clay-sand mortar

First you need to determine how much material you will need. The calculation is as follows: when laying 50 bricks flat with a seam thickness of 3–5 mm, about 20 liters of masonry mixture will be required (we increase by 15–20% if we are building a Russian stove).

Clay mortar is used for the main structure of the furnace; it can also be used for lining. Consists of clay and water. Sometimes filler is added: sawdust, shavings, construction sand. The clay mixture is prepared in the following proportion : 1 part filler is added to 2 parts clay. More often than others, clay-sand mortar is used for laying the stove.

The ingredients are mixed into a homogeneous mass until creamy. The masonry mass should come off the shovel well and leave no traces. Also, no separated water should appear on the surface - if this happens, you need to add sand. To give greater strength, salt is added to the solution: 100–250 grams per bucket of solution. Cement is used less often - 750 grams per bucket.

How to prepare mortar for laying stoves is demonstrated in the video. At the same time, you will see the consistency to which you need to soak the clay.

Sand-cement mortar is used to level out uneven surfaces and oven cladding (tiles, mosaics, stones). Cement mortar for the furnace is used to seal joints when laying the foundation. It is prepared as follows: measure out the required amount of construction sand and cement, mix well, fill with water to the desired consistency - such a state when it is sufficiently mobile and is squeezed out of the seam without much pressure. The proportions of materials depend on the brand of cement composition, most often 1:2.

Limestone is used as a mortar for plastering stoves, for laying foundations and pipes. Its preparation is completely different. First, the lime is slaked and kept in a special pit for about a week. After this, prepare a solution with sand. The ratio depends on the fat content of the lime (usually 1:2 or 1:3).

Lime-clay mortars with the addition of asbestos are also used for plastering the stove to give greater strength. The proportions of the solutions are as follows:

The preparation technology consists of combining all the dry ingredients and adding clay, gypsum or milk of lime diluted with water. Then the components are mixed until smooth.

There is a fireproof (fireclay) mortar for laying the core of furnaces. To prepare it, mix fireclay and fireclay in a 1:1 ratio, then add water (a quarter of the clay mass) and mix well.

This is what a good mortar on fireclay brick looks like

It is necessary to monitor the quality of the solution. After all, only a sufficiently plastic composition can ensure good adhesion of the stove masonry and tightness of the seams.

Brick chimney mortar

When building stoves and fireplaces, bricks are held together with a special mortar. There are special requirements for solutions.

After all, it must not only firmly connect the bricks to each other, but also withstand high temperatures.

In addition, the solution must be sealed. It is not allowed to crack. As a result of this, smoke and carbon monoxide can enter the room.

Which can cause irreparable harm to health or lead to death.

Requirements for solutions

If you look at the rules established for the construction of stoves and fireplaces, in the section of brick smoke ducts, at this address - files.stroyinf.ru/Data2/1/4293786/4293786504.htm#i1203891, you can see the requirements for solutions.

These rules specify the requirements for the location of objects, materials, and so on. Among other things, the requirements for solutions are indicated.

For example, it says that when constructing brick chimneys for stoves and fireplaces, the following solutions are used:

lime or lime-cement - for erecting a chimney in the wall of a building;
lime-cement - for masonry above the attic floor;
cement - for masonry above the roof.

That is, the higher the chimney, and the less it is exposed to high temperatures, the more cement should be used in the solution.

Proportions of lime-cement mortar

Finding out the name of the solution is only half the battle. All that remains is to determine its exact proportions.

The proportions of the solution depend on many factors and the desired result.

Under moderate conditions and low strength requirements, less cement is added.

In harsh conditions and increased strength requirements, more cement is added.

For example, moderate-condition lime-cement mortar contains:

Cement - one part;
Lime - one part;
Sand - six parts.

The same solution, but for more severe conditions and with increased strength, contains:

Cement - one part;
Lime - 0.5 parts;
Sand - four parts.

If there is an excess amount of lime, the lime-cement mortar turns out to be too greasy. Then it becomes very deformed after drying. And if there is not enough lime, the result is an inelastic solution that is difficult to work with.

The indicated solutions may require different amounts of water. It all depends on the quality of cement, sand, humidity, and so on.

Therefore, it is recommended to take approximately one part of water to start kneading. And then, during the kneading process, gradually add water to the desired consistency.

Lime composition for chimney

The body of the stove inside the house is built using clay mortar. But, as already mentioned, it is not suitable for external elements. The chimney, starting from the attic level, is laid out using a lime or lime-cement mixture.

To prepare the first of them, lime dough is mixed with sand and topped up with water to the desired consistency. The lime dough itself is a combination of lime (quicklime) and, again, water in a 3:1 ratio. During mixing, the quenching reaction occurs, so you need to wait until it is completed before preparing the lime mortar. Then sand is added to the dough in proportions of 3:1 and diluted with water.

Many stove builders believe that a cement-lime composition for laying a chimney is preferable - it has higher ductility and strength. Its preparation consists of the following steps.

For 10 parts of fine sifted sand, take 1 part of Portland cement, and the dry components are thoroughly mixed.
2 parts of lime are added to the composition.
Water is poured in portions, with mandatory intermediate stirring.

The consistency of the resulting solution should be standard, similar to thick sour cream.

Mortar for laying a brick chimney

When building a furnace, the difficulty often arises as to what mortar to use for laying the pipe. After all, red ceramic brick does not interact with all compounds. The same mortar that was used in the construction of brick walls is not suitable for laying a chimney. However, its use is not recommended, as it will not withstand high temperatures. There are special heat-resistant compounds for heating systems.

Masonry mortars for brick kilns

The strength, reliability and pleasant appearance of stoves and fireplaces largely depend on the quality of the masonry mortar with which they are laid. If there is not enough or too much of any component, the seams will crack. As a result, smoke from the stove will begin to flow into the room, and fuel costs will increase, since due to excess air supply it burns faster. Or you don’t have to waste time calculating the proportions, but buy a ready-made composition.

The masonry mixture for fireplaces and stoves consists of a binder, filler and water. If there is only one knitting element in it, then it is considered simple, if there are two, then it is complex. The main characteristics are strength and ductility. At the same time, according to plasticity, they are divided into 3 types: skinny, normal, fat. For laying fireplaces and stoves, the best option is the second one, since it does not crumble when dried. When heated, it expands in almost the same way as brick. Oily has excellent ductility, but when it dries, it will crack.

Components of mixtures and their types

Depending on the type and method of use of the structure, a binding solution is selected. During operation of the furnace, smoke, evaporation and chemical acids act inside the pipe. Therefore, it is important to properly prepare the solution for the chimney. Typically, it consists of a solvent (i.e. water), binders and aggregate. When hardened, the volume decreases, and the filler does not allow it to crumble and retains its original size. The binder component performs an important function - when it transforms into a solid state, it forms a strong bond between the masonry material.

The mixtures differ in some characteristics:

By dry density: light;
heavy.

By astringent property:

lime;

cement;

clay;

mixed.

When facing stove structures with bricks, the appropriate type of mortar is used.
Mortars are also divided into masonry (laying foundations, bricks, stones, chimneys), finishing (lining furnace structures with bricks) and special ones. A simple mixture consists of only a filler and one viscous component, a mixed and complex mixture consists of several binder components and fillers. In a complex composition, the name is determined by the main component with a strong astringent effect.

If you choose the right thickness of the mixture, it will turn out homogeneous, without unnecessary compounds and will be easily squeezed onto the brick with light pressure.

Lime mixture

The preparation method depends on the properties of the lime:

When quenching slowly, pour the component into a quarter of the volume and add water. After cracks form, carefully stir, adding water little by little in small doses until a liquid state is obtained (milk of lime).
For medium slaking, add ¼ of the lime and fill half with water. After steam has formed, stir thoroughly and add water until it is completely extinguished.
For quickly slaking lime, pour ½ water and add lime. After steam appears, mix thoroughly until the quenching process is complete and rub through a sieve. If the solution turns out thick, add more water until smooth.

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Clay mortar

To obtain the mixture correctly, clay is placed on the prepared boards. Place in layers, wetting each layer with water until softened. A layer of sand is placed on top. Its proportion with clay is 1:1 or 1:2, and the amount of water is a quarter of the volume of clay. After this, the solution is mixed and divided into layers with a shovel, collected into lumps, removing unnecessary particles, and mixed again until a homogeneous mass without clots is obtained. The finished solution should not be liquid or spread.

Cement mixture

This composition is the most durable. There are two ways to receive:

A dry mixture of sand and cement is mixed, at the same time lime is prepared to the state of sour cream, then the compositions are combined and thoroughly mixed. To obtain the required thickness, add liquid and stir to the desired consistency.
Mix cement with water and add to the prepared solution of lime and sand. This mixture is more plastic, sets quickly, but is less durable than with the first preparation method. The ratio of materials ranges from 1:1 to 1:6.

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Lime-gypsum composition

To plaster a brick oven, use this mixture. It is inexpensive, and with the addition of cement and lime it can be used for laying a brick chimney. This composition is easy to work with and hardens quickly. The main thing is to correctly calculate the proportions and obtain the required homogeneous consistency.

Methods for slaking different types of lime

To prepare quick-quenching lime, pour water into the slaking box up to half of its walls. Then lime is added in several additions, distributing it evenly. When steam occurs, the lime is intensively mixed, breaking up large pieces and pouring water until the steam stops being released. Add water to the slaked lime to obtain a homogeneous milk of lime, and leave for a while to slak out the remaining pieces. Then the whole mass is mixed and passed through a sieve.

Water is added in small portions - this is necessary to prevent burnout and drying out of the lime.

To extinguish medium-slaking lime, you need to put boiling lime in the extinguishing box to a quarter of its height and pour water to half the layer. When steam appears, the lime is stirred and the pieces are broken. Add water in small portions - this is necessary to prevent burnout and drying out of the lime. When the steam emission ends, you need to add water, mix everything and after a while pour the milk of lime through a sieve into a creative pit or container.

Slow-slaking lime is poured into the slaking box up to a quarter of the height of its walls, moistened with a small amount of water and kept until signs of slaking appear (cracks, etc.). After this, small portions of water are carefully added to the lime so that the lime that has begun to slak does not cool. After slaking, the lime is diluted with water to obtain lime milk, kept for a short time and drained through a sieve for storage. In the cold season, to speed up slaking, slowly slaking lime is poured with hot water.

The use of mortars for laying brick chimneys

Lime composition is used for laying the furnace pipe. A mixture of water and lime with the addition of sand is prepared. The mortar prepared according to the rules can withstand high temperatures, is resistant to moisture and ensures the reliability and durability of the oven, connecting the bricks with high quality. To create a more durable mixture, cement is added, and gypsum is added to speed up hardening during putty work.

The clay composition is not suitable for laying a chimney, as it does not withstand moisture, which leads to the formation of cracks. But at the same time it is resistant to temperature increases, therefore it is used as a mixture for the main part of the furnace structure. However, such a solution should not differ from the composition of the brick, be durable and not emit fumes. To increase strength, add 100-200 grams of salt an hour before mixing. The masonry is made on the basis of fire-resistant clay and fireclay bricks. The cement mixture is used to build pipes. It sets quickly, so it is necessary to work with it within an hour after mixing, otherwise the solution will begin to lose strength. After laying, the solution is covered with shavings and moistened with water for 4-5 days.

Types of solutions

To lay a stove, you will need at least three types of masonry mortar - this is not counting the final finishing with plaster. In this regard, the process looks like this.

Laying the foundation. A concrete mortar made from cement is most suitable here, since the base must withstand significant loads due to the pressure of the structure as a whole.

The actual laying of the furnace. Clay mortar is most suitable for joining bricks into a single whole. The classic cement mixture is not suitable due to the low heat resistance of the material.

Chimney outlet. It does not require increased fire resistance, but the masonry mortar is required to be resistant to atmospheric influences, since this part of the furnace is fragmentarily located outside the room. Clay mortar is not suitable, as it will become limp due to humidity. Therefore, lime-based mixtures are used to construct the pipe.

Professional stove makers prefer to prepare masonry mortar themselves. However, it is quite acceptable to use ready-made mixtures sold in specialized stores.