In the process of operation, the structures of buildings, structures, as well as various kinds of communications are constantly exposed to adverse weather factors. In order to protect them from contact with moisture and premature destruction, waterproofing agents are used. There are many varieties of such materials. At the same time, bitumen mastic is one of the most popular. This tool is easy to apply and is inexpensive. Before starting treatment, it is important to make the appropriate calculations and find out the exact consumption of bitumen mastic per 1 m2 of waterproofing. This will allow you to work as efficiently as possible and prevent unnecessary expenses.
Purpose of bituminous mastic
This popular waterproofing material can be used to process a wide variety of structural elements of buildings and structures. Most often, bitumen mastic is used to coat the underground parts of the foundation or socles. Also, this tool is used for waterproofing flat roofs. Mastic is also used to protect basement floors and cellars from the penetration of groundwater. In this case, the processing can be carried out both externally and internally. A very effective protection using this material can be done for underground parts of various kinds of small architectural forms (arbors, swings, children's slides, etc.). The lower ends of the fence posts are also often treated with this particular material.
Sometimes mastic is also used for gluing strips of rolled waterproofing materials on different surfaces. This is done, for example, when finishing roofs or foundations with roofing material. Often, mastic is also used for processing pipes and communication wells.
Material types
The consumption of bitumen mastic per 1 m2 of waterproofing depends primarily on its variety. This material is a mixture of organic substances with astringent properties. Bitumen mastic can be classified according to several criteria. Distinguish, for example, its cold and hot varieties. In the second case, the mastic is melted in a barrel before use. The cold version of the product initially has a liquid consistency.
In addition, mastic can be one- or two-component. The first option can be used immediately after purchase. Two-component mastics consist of 2 separate products that must be mixed before use. By type of basis, such agents are classified into rubber (elastic), oil and ordinary polymer.
Consumption of bitumen mastic, depending on the consistency
Of course, the thicker the material, the higher its consumption. You can find out exactly how much mastic is required for processing 1 m2 of the surface if you read the instructions for use. Manufacturers indicate this indicator without fail. Consumption of hot mastic is usually less than cold. The fact is that the melted heated material lays on the surface as evenly as possible, does not form bumps and pits. In addition, hot mastic practically does not shrink. As a result of this, consumption is also reduced. The consistency of cold mastic is usually more viscous than that of melted. Therefore, it is necessary to spend quite a lot on surface treatment.
Consumption depending on the number of layers
One-time coating of the foundation or flat roof with mastic usually does not give the desired result. Therefore, surfaces are treated using this material most often in 2-3 layers. This allows you to completely eliminate contact of the oiled surface with moisture. The consumption of bitumen mastic per 1 m2 of waterproofing is usually indicated by the manufacturer for only one layer. Therefore, the number in the instructions for the calculation must be multiplied by 2 or 3.
Solids and Layer Thickness
Cold mastic, unlike hot mastic, usually produces very strong shrinkage. The amount of material present on the treated surface after the evaporation of liquid substances is called the dry residue. This indicator for different types of mastics is not the same and can be 20-70%. Accordingly, material with a dry residue of 20% will be spent about three times more than funds with an indicator of 70%. Thus, the higher this indicator, the faster and easier it is to complete the work.
Consumption depending on the application method
It is supposed to work with bitumen mastic at a temperature from -10 to +50 ° . Before use, the material must be thoroughly mixed. Mastic is applied to the surface, depending on the variety, with a brush, spray, spatula or roller. In the latter case, the layer is usually more even. And consequently, the consumption of bitumen mastic per 1 m2 of waterproofing is reduced. Also, the amount of money spent can be reduced if you use a spray. In this case, it is easy to meter the material with great accuracy.
Average consumption
For applying a layer of two millimeters, approximately three and a half kilograms of mastic per square meter in the dry residue is required , in 1 mm - 1-2 kg. When processing roofs, 3-4 layers of material are most often applied. Therefore, the consumption of bitumen mastic per 1 m2 of roof waterproofing increases to 3-5 kg / m 2 . When gluing roofing material on the surface in a single layer, it usually takes no more than 250-800 grams of the product per 1 m2. The fact is that the solid material in this case is usually not applied.
Consumption of bitumen mastic per 1 m2 of pipe waterproofing usually does not exceed one and a half kilograms. In this case, the most commonly used oil type of material. Mastic is applied to pipes in 1-2 layers. In the latter case, the consumption, of course, will increase by about 2 times and amount to 2-3 kg.
What other factors can influence
The amount of mastic needed for surface treatment depends on the variety of the latter. When waterproofing concrete, as a very porous material, it takes more money than when coating wood. The fact is that in this case the surface simply absorbs part of the mastic. The tree also has pores, but small and not in too many. The consumption of bitumen mastic per 1 m2 of waterproofing of a well from concrete rings, for example, will be greater than for a monolithic tape of the base of the house (up to 3 kg). The same applies to foundations assembled from slabs. The fact is that in this case, some of the material incorporates joints.
In addition, the amount of money spent depends on whether the surface is processed - vertical or horizontal. So, the consumption of bitumen mastic per 1 m2 of floor waterproofing will be approximately 700-800 g. At least 1-2 kg of the product will be used on the walls when applied in one layer.
How to reduce mastic consumption
To save money, the processed material can first be primed. Most often, a primer is used for this purpose. Coat the surface with it usually using a brush or roller. Primed with this tool is usually in one coat. The primer dries in a few hours.
In addition, in order to reduce the consumption of bitumen mastic per 1 m2 of waterproofing the foundation or roof, you should carefully prepare the surface. The fewer cracks and chips on it, the cheaper the waterproofing will cost.
Mix cold mastic thoroughly before use. Smear vertical surfaces from top to bottom. If you do the opposite, the consumption of mastic will increase. Yes, and the operation itself in this case will be more difficult to perform due to the resulting drips. Before applying each subsequent layer, you should wait until the previous one has completely dried. It is easy to check that the surface is ready for new coating. To do this, touch her finger. If it does not stick, then you can apply the next layer.