- Properties of masonry mortar
- The role of sand in solution
- The main working property of the solution is plasticity
- Types of factory solutions
- Cement Saving Recipe from a Professional Bricklayer
- How much can you save
- Expressing savings in money
From the article you will learn about mortars for masonry of various materials, about their properties and advantages. We will tell you about the difference between factory and homemade solutions – we will describe the benefits of each type. The article contains a training video and tables with prices for ready-made factory masonry mixes.
The main component of any mortar is a reactive binder, which envelops small aggregate particles and binds them securely during hardening. The most common binders:
- Mixtures of the listed components.
They can act as both main and additional astringent. The aggregate is usually sand.
The designation of solutions, adopted in the standards of GOST and SNiP, is subject to the following rule: the first digit is a unit – an indicator of the volume of the main binder. The last digit is the amount of aggregate in relation to the binder. For example, cement-sand mortar 1: 3 for 1 kg of cement accounts for 3 kg of sand. In complex solutions, between these figures, indicators of auxiliary binders are introduced. For example, cement-lime mortar 1: 2: 4 means that 1 part of cement accounts for 2 parts of lime and 4 parts of sand.
It should be noted that the masonry mortar can also be used for plastering walls. The difference between masonry and plaster mortars is the proportion of cement – in plaster 1 part of cement to 4-5 parts of sand according to GOST.
Properties of masonry mortar
The main purpose of the masonry mortar is the construction of walls from separate blocks. There is only one requirement for the blocks – the porous structure of the contact plane. Penetrating into pores and hardening in them, the solution binds the blocks together along vertical and horizontal seams.
Requirements for mortar for masonry:
- Plastic. The property of a mixture to take a given shape.
- Rigidity. It is determined by the gravitational draft of the cone from the working mixture in 1 min. An ideal masonry mortar has no random settlement.
- Profitability. The main binder is the most expensive component of the mixture. To activate it and reduce consumption, various additives and auxiliary binders are used.
The listed requirements apply to all types of solutions, including special.
The role of sand in solution
This familiar component can vary significantly in composition and affect the plasticity of the solution. There is always a certain percentage of clay in the sand, which has the property of retaining moisture. This useful property has a positive effect on the plasticity of the finished mixture and allows you to undergo a chemical hardening reaction – water does not evaporate prematurely.
On the other hand, an increased percentage of clay and impurities (especially organic matter) leads to the fact that the solution becomes too plastic and sticky – it is difficult to remove it even from the walls of the concrete mixer. In this case, the dried solution becomes weak, since the clay particles are smaller than the cement particles.
If you are preparing a mortar for masonry yourself, pay attention to the consistency of wet sand – it should not stick together and get your hands dirty (the “dirt” of wet sand is clay).
The main working property of the solution is plasticity
This indicator is one of the decisive ones. It is the retention of moisture that creates the condition for the hardening of the solution. The primary natural plasticizer – clay – does not give the necessary properties to the solution and more components have to be added. Plasticizers were added to the solution as they were invented.
Lime. The most affordable, popular and proven plasticizer. This substance has many purposes and is used in horticulture. Add 4 parts of lime to one part of cement.
Liquid soap. Perfectly plasticizes any mixture. Another most valuable property of this component is the retention of salts inside the dried solution. This avoids efflorescence on the wall surface. 10-15 g of soap, shampoo or dish detergent is enough for 1 kg of ready-mixed mixture.
Special plasticizers. These are modern aqueous solutions or powders that help retain moisture in solution. Their cost is slightly higher than ordinary liquid soap, but they allow you to get the best possible result..
Types of factory solutions
Today, on the shelves of hardware stores, you can find many varieties of ready-made dry masonry mixes. They have the following advantages over “homemade” ones:
- High-quality components, free from impurities.
- Carefully calibrated composition and proportion of components.
- Orientation for a specific task.
- Convenient packaging (especially important in an apartment).
For laying bricks and blocks.Usually contains a cement-sand mixture with a dry plasticizer and additives for long storage. Suitable for bricks, aerated concrete, cinder block, concrete. You can find a tinted mixture.
Table. Dry factory masonry mixes
Name Packing, kg Packing price, cu e. Price for 1 kg, cu e. “MONOLITH” frost-resistant 25 3.2 0.13 “KNAUF Cottage” 25 3.8 0.15 “Plitonite Masonry Master” 25 five 0.2 Perfekta “Linker” (color) 50 6.4 0.13 Klya 75 25 3 0.12 Terta “Tertamiks” (color) 50 6.5 0.13 “Will found Brickform T-111” 25 4.2 0.17
For laying fireplaces and stoves.Clay-sand mixture with the addition of fire retardants. It happens on the basis of kaolin or quartz clay. Such a solution can be prepared using ordinary clay, but only a good master can determine its suitability for the oven by eye. In the factory fireplace mix, the clay undergoes laboratory tests.
Table. Dry mixes for laying fireplaces and stoves
Name Packing, kg Packing price, cu e. Price for 1 kg, cu e. “DIOLA +1200 ° C” (D-375) ten 2.5 0,4 “Pechnik” 18 7 0.38 “Crystal Mountain” 25 4.1 0.16 “Real Oven” 25 5.5 0.22 “Plitonite SuperFireplace Refractory” 20 12 0.6 “Plitonit SuperFireplace ThermoKladka” 20 5.45 0.27
For aerated concrete masonrycommon tile adhesive is often used. It is a super-flexible mortar that is applied to the block with a comb-trowel. This is possible due to the perfectly flat and porous planes of aerated concrete.
Table. Dry mixes for aerated concrete
Name Packing, kg Packing price, cu e. Price for 1 kg, cu e. “Resolit” RDV-2010 25 2.5 0.1 “KREPS KGB” (for aerated concrete) 25 3.36 0.13 “MIXITY Aerated concrete” 25 3 0.12 CBS Block 20 3.45 0.17 Bonolit 25 4 0.16 BERGhome MK30 25 3.6 0.14
Of course, factory masonry mortars are significantly more expensive than self-prepared ones. However, they are much more convenient to use in cases where speed and purity of the process are important. The cramped conditions of city apartments do not even give extra centimeters for storing and processing material.
Cement Saving Recipe from a Professional Bricklayer
Recommendations on how to get an ideal mortar without overconsumption of cement:
- Use a concrete mixer (mixer) or other type of mechanization. With manual mixing, the solution does not mix completely, the reaction does not proceed properly. The result is loose seams that do not have adequate strength..
- First, add the required amount of water to a running mixer (1 part – 10 l).
- Then add 1 part (10 L bucket) of cement. Wait for shuffle.
- Add the sand one bucket at a time, gradually. Make sure that the sand is completely mixed and the consistency is homogeneous – otherwise the mortar will be dry and hard, unsuitable for masonry.
- Add DOMOLIT-TR lime substitute or an analogue to the entire volume of the solution in the mixer – 100 g.
- Add any liquid soap – 100g.
- Stir the solution for 3-5 minutes until a pasty consistency is obtained.
Masonry mortar recipe on video
- Water – 1 part.
- Cement – 1 part.
- Sand – 5 parts.
- Lime substitute (plasticizer) – 0.01 parts (100 g with a bucket of 10 liters).
- Liquid soap – 0.01 parts (100g with a bucket of 10 liters).
With this preparation technology, the solution is saturated with micro-air bubbles, which prevent it from settling. In addition, these bubbles act as microscopic spheres, perfectly distributing the load. This explains the high quality of the frozen solution with half the amount of cement than in GOST.
How much can you save
Note.The calculation does not include the cost of sand and water.
If you perform the described mixing, we get 60 liters of ready-made solution * using 10 liters of cement. With a traditional mixing of 1: 1: 3 ** from 10 liters of cement only 40–42 liters will be obtained. The difference in volume is about 20 liters. That is, having 10 liters of cement, we can get plus 50% of the finished solution compared to the conventional method. It turns out that for 60 liters of ordinary mortar, we need about 20 liters of cement.
* The sum of all parts is 70 liters, but in practice the cement dissolves in water, and water fills the space between grains of sand and the output volume is less than the sum of the volumes of the parts.
** With the sum of the volumes of the components equal to 50 liters (1 – cement, 1 – water, 3 – sand), the volume of the finished mixture will be about 42 liters.
Expressing savings in money
- Cement. It is known from practice that a 50 kg bag of cement has a volume of 42 liters (we accept 40). The cost of the bag is about 4 USD. e. The price of 1 bucket of 10 liters is 1 cu. e.
- Liquid soap costs about 2 cu. e. for 5 liters, 0.4 cu. e. for 1 liter, 0.04 cu e. per 100 g.
- DOMOLIT-TR plasticizer costs 4 USD. e. for 1 liter, 0.4 cu. e. per 100 g.
The cost of 60 liters of ordinary mortar: 2 buckets of cement x 1 cu. e. per bucket = 2 cu e.
The cost of the plasticized mortar: (1 bucket of cement x 1 cu) + 0.04 cu. e. liquid soap + 0.4 cu. i.e. plasticizer = 1.44 c.u. That is, we accept 1.5 cu. e.
A net savings of 25% relative to a simple mortar. In this case, the solution acquires quality properties – plasticity, frost resistance and increased strength.
Indeed, additives and additives can reduce cement consumption – those who have been working with mortar for a long time know about this. Each master has his own staff, with whom it is most convenient for him to work. Against this background, one should be careful about masters who ignore progress and do not use antifreeze and plasticizing additives. Correctly selected masonry mortar is a guarantee of reliability and 100% implementation of the technology for the construction of stone walls.