The roof of the building, in whatever region the building was located, is constantly affected by the phenomena of the atmosphere: rain, snow, wind and ultraviolet. It is for this purpose that it serves, since the roof protects the building and the person from the effects of weather conditions. But the roof itself needs protection, because moisture can destroy all its elements, leading to and in disrepair. That's why a layer of waterproofing is laid on the roof, which serves as a barrier, making it impenetrable. To date, the market can offer you a variety of materials for high-quality waterproofing. One such material is liquid bitumen for a soft roof.
This is a universal material that is used for various purposes: for fixing roll materials, fixing some types of linoleum and laying parquet. Nevertheless, the main purpose of bitumen mastic is to protect the roof surface from moisture and water. Why is liquid bitumen popular as a waterproofing soft roof? What are the characteristics of the material? How to calculate the consumption of material on the entire roof? And how to fill the roof with bitumen? All this we will talk about in the article.
Characteristics of bitumen for roofs
What is liquid bitumen? It is an organic insoluble substance resembling resin. Its density is from 0.95 to 1.5 g / cm3. It consists of carbohydrates and nitrogenous, sulfuric, metal-containing and acidic derivatives. The bitumen for soft roofs gained popularity because of its technical characteristics. What are they?
- High elasticity of waterproofing.
- Long service life.
- Economical material.
- Increased resistance to insolation.
- A small proportion of bitumen.
- Good resistance to aggressive environment.
- Can be painted in almost any color.
- Easy to apply material.
- Availability of raw materials as a waterproofing soft roof.
- Viscosity and low consumption.
- Refractoriness of the material.
- Absence of seams and joints.
- High tensile strength.
There are several varieties of bitumen: natural and building. Natural bitumen is obtained when extracting petroleum products from various rocks. It is characterized by increased resistance to the effects of liquids, alkalis and acids. As for construction bitumen, it is a product of mixing and oil distillation with various building components. The material has a high resistance to wetting and the influence of ultraviolet rays.
Types of bitumen mastic
Among other things, bitumen for roof waterproofing can be divided into these types:
- Material of cold application. What he really is? This is a homogeneous bitumen, which is already ready for pouring the roof. To obtain a liquid consistency, the continent is diluted with various solutions. There is one important point - after you have diluted it, the mixture must be used immediately. Otherwise, the bitumen will return to its original state. Some types of cold bitumen must be heated to 30-40 ˚C before applying to the roof.
- Material for hot use. A feature of this waterproofing for the roof is that it needs to be heated up to 150-180 ˚C. Since the process is quite dangerous for health, you need to comply with safety regulations. It is better to entrust this work to qualified professionals. After heating, the roof is poured. With the passage of time, the mastic solidifies and acquires the right shape and properties.
- Bitumen on a water basis. This layer of waterproofing is considered the most environmentally friendly. The composition is simple enough, and it's easy to work with. The application process is also safe, since the mastic consists exclusively of natural substances that are not toxic.
- Modified bitumen. This is the material that is obtained by mixing mastic and special polymer additives. Due to polymers, the modified bitumen for the roof has improved characteristics. Frost and heat resistance is higher, as is resistance to load. Moreover, the modified material is more elastic, durable and has a high tensile strength. Therefore, if you decide which material is best suited for waterproofing the roof, then we recommend that you choose a modified one.
If you have already decided on a choice, then you need to purchase the product. But the question arises: how much it is needed for the waterproofing of the soft roof, and what is the consumption? Let's find out.
Consumption of mastic for waterproofing
When buying, immediately pay attention to the product packaging. Often, manufacturers themselves indicate the consumption per 1 m2. If it is, there will be no problems. But how to be when the expense is not specified? It can be calculated independently. To do this, pay attention to the recommended thickness of the waterproofing, which will depend on the consumption of 1 m2. The thicker the layer, the more mastic will be needed. How to make calculations?
For example, to cover the roof with a layer of 2 mm thick, 3-4 kg / m2 in the dry residue. What is it? The amount of mixture remaining after the drying of the mastic. Modified or another kind has a dry residue at a level of 20-70%. To create a monolithic layer of the same thickness with a 20% residue, more mixture is required than at 70% of the residue. The conclusion is that the more dry residue, the more economical it is to perform works for the construction of a soft roof. Below is a table from which you can find the material consumption at 1m2 roofs.
Let's say you need to know the consumption of the composition on a surface, the size of which is 10 × 5 m, the layer thickness of 1 mm. First, find out the surface area. As you know from school, you can find the area by multiplying the height by the width: 10 × 5 = 50 m2. Now look at the table. Depending on the choice of mastic, the flow rate may vary. Choose the kind that you will use. For example, you work with a hot mixture. If the 1m2 at a layer thickness of 1 mm it is necessary 2,5-3,5 kg, then at 50 m2 you need 125-175 kg of the mixture (we multiply the area by the consumption). That's all, now you know how much mix is needed. And if you want to make two layers, then multiply this by 2.
So, everything is ready to start work on applying bitumen for waterproofing the soft roof. Consider the technology of application.
Stage 1 - prepare the surface
Every master knows that the first step is to prepare a basis for further work. Remove all debris, sand, dust, water and other contaminants from the surface. Wait until everything is dry. Then, treat the roof with a special bitumen primer - fine bituminous crumb, diluted with water. It forms a good emulsion. After the mixture is applied, part of the water evaporates, the part is absorbed into the material, and the crumb fills all pores. This ensures good adhesion between materials. Now everything is ready for further work.
Stage 2 - Preparation of mastics
Open the product and mix the contents thoroughly with a mixer and a construction drill. To make it convenient for you to apply the material, it can be heated to a temperature of 30-55 ˚C in an open metal tank. After this procedure, the mixture becomes more plastic. In addition, in a heated form, due to its fluidity, it penetrates more qualitatively into all the pores and will hold firmer on the surface of the soft roof.
Also, you can dilute the bitumen with a solvent (gasoline or white spirit). This will also contribute to an increase in ductility, and the mixture will be easier to apply.
Once you have prepared the mixture, immediately begin to apply it.
Stage 3 - application of material
It was the most responsible time. All the work can be done in several ways. The first of them - with a roller or brush. The method is fairly simple and fast. Bitumen is applied in exactly the same way as ordinary paint. Using roller movements, apply the material to the surface from the edge, but do not smear it. Simply dip the roller or brush into the bitumen and apply it to the surface. In such a simple way, trim the entire area until there are no untreated areas. Now let the bitumen dry completely. Then reapply the bitumen layer in the same way.
The second method of application is the pouring of bitumen. The word itself already indicates what needs to be done. It is important to heat the bitumen to a state in which it will have a high plasticity and ability to flow. After that, the mastic is poured onto the roof surface and leveled with special scrapers, rollers with an elongated handle or mops. This method has its pros and cons. The advantage of the method is the speed and simplicity of the work. And disadvantages include increased material consumption.
The third way is more technological and requires special equipment. The process itself passes quickly, qualitatively, and the material is consumed economically. What is it about? On machine application of bitumen. For this purpose, an airless sprayer is used, which evenly applies bitumen to the surface. This method is really good, but in the absence of technology it is impossible. What exactly method to apply bitumen as insulation of a soft roof is up to you. The main thing is a qualitative result!
In the end, I would like to quote some figures concerning the price of bitumen. It depends on the manufacturer, the packaging and the recipe of manufacture. The most economical modified bitumen products "Mastic MBH bitumen-polymer", 16 kg will cost you from 970 rubles. The most expensive is "Mastic bitumen-rubber". The price for 20 kg of the mixture starts from 1980 rubles. Mastic hot application is more advantageous in terms of price, as for a bag in which 30 kg of the mixture you will pay about 1600 rubles.
Waterproofing on the roof under profiled
Steam insulation on the roof for profiled flooring
Color corrugated roofing
How to make a roof of shingles