What is bitumen is known not only by builders, but also by many consumers. This material was widely used several decades ago for covering small outbuildings, arranging a moisture barrier between the foundation and the wall of buildings, and for many other purposes. But pure bitumen is not the best option for the production of roofing. After all, it lends itself to aging, becomes brittle and hard under the influence of oxygen and sunlight. As a result, cracks appear on the surface, and it loses its waterproof function. To get rid of these shortcomings, oxidized bitumen is used for the production of roofing.
Production Features
Production of bitumen is a complex technological process that is carried out on the territory of oil refineries. The raw material is oil, and not one variety, but several, which are carefully selected. The quality of the finished product depends on the quality of the source material.
The production of oxidized bitumen is a forced process and is carried out in a special plant. It heats up the feedstock.and oxygen passes through it. The feedstock can be fuel oil, tar, cracked residues, semi-tar, or a mixture thereof.
Benefits and Features
The consequence of the oxidation process will be the acquisition by the product of characteristics important for operation, which include:
- Changing the heat resistance of the coating from the initial +45 degrees to the final +120 degrees.
- By stopping all chemical processes, the roofing product acquires the required rigidity.
- Better flame retardant than non-oxidized counterpart.
- No fumes or bad smells when heated.
- Because of the improved quality, bas alt granulate does not crumble from the surface.
- The coating retains its appearance, does not blister or crack.
- Improved wind resistance. Due to the fact that the rigidity of the material has increased, the coating easily resists even the strongest winds.
The oxidation process will not end there - it will continue after the installation of the roof for a certain period during its operation.
Disadvantages of oxidized bitumen
Unfortunately, the oxidation process gives the coating some disadvantages:
- Brittleness at sub-zero temperatures - the material hardens in the cold, becomes rigid. Therefore, it cannot be used for mounting. This is a significant disadvantage for professional builders who have to work not only in the summer.
- Due to the fragility of the canvas, if necessary, it is difficultto repair in the cold - at the slightest load, for example - it is enough to stand on the roof, it begins to crack and break.
Production of modified bitumen
What is modified bitumen? This is the name of the material, in the initial mixture of which a certain type of modifying substance is added. This is necessary so that the finished product for roofing can withstand various weather conditions. What does the addition of modifiers give? Mixing bitumen with polymer added in the correct proportion gives the final product important performance properties:
- UV resistant.
- Good adhesion.
- Ability to keep fit.
- Resistant to sudden changes in temperature.
Many consumers wonder if the added polymer is harmful to people and the environment. The following fact testifies to how safe the thermoplastic is - after several years of operation, fungi, moss and other biological organisms begin to grow on the surface of the coating. To destroy them, it is enough to treat the surface with any substance, the basis for the creation of which was copper sulfate.
Comparison of characteristics of oxidized and modified bitumen
The properties of oxidized bitumen and SBS-modified are largely the same. This is a long-term operation, excellent appearance. But there are also differences. To understand which of the materials has the bestindicators and is more suitable for a particular object, it is necessary to compare their characteristics and consider the differences.
| Description of features | Oxidized bitumen | Modified bitumen |
| Temperature range at which operation is possible. | -55° C to +120° C. | From -25° to +120° C. At lower temperatures, coatings begin to crack and crumble. This leads to a violation of the tightness and a change in the appearance of the roof. |
| Adhesion. | High adhesion. Thanks to this, the material has excellent wind resistance - even in strong winds it does not break off the roof. In addition, the granulate adheres perfectly to its surface. | Minimal adhesion, which can cause granulate to crumble. |
| Quality. | The end material is of high quality, independent of the quality of the raw material. |
The quality of the finished roof depends entirely on the quality of the raw materials. If it did not have the right quality, manufacturers have to use various stabilization additives in order to achieve a good quality of the final product. |
| Flexibility, elasticity | High rate | High, but only at positive temperatures. |
| Use of chemical builders | Not available | Used to extend the life of the roof. |
| Green | Does not contain harmful or chemical substances. Therefore, it is considered safe for humans and the environment. | May emit harmful substances, although in small quantities. |
Conclusion: although the modified bitumen is cheaper, according to various indicators it is slightly inferior to the oxidized counterpart.
Mounting Features
As they say about flexible tiles, reviews of experienced builders, if the laying of each type of coating was carried out correctly, there are no significant differences in the behavior of the roof. But there is one important nuance. It is necessary to choose and install a coating from both materials, taking into account their characteristics and properties. So, in summer it is more convenient to work with modified bitumen - it has greater heat resistance and has proven itself well at high temperatures. If an oxidized analogue is used for installation, it is better to work with it in winter. It remains flexible even at very low temperatures.
Conclusion: you can work with any material, if the work is carried out according to the manufacturer's recommendations and strictly follow all their instructions, the roofing can be used for many years, retaining its characteristics.
And what do the reviews of the owners of houses covered with similar material say about flexible tiles? The most important thing that each of them says is high aesthetics.coverage and reliability. After several years of operation, the surface remains intact and fulfills its function.
Types of modified bitumen
Depending on the type of added modifier, there are two types of modified bitumen:
- SBS (rubber bitumen). To get it, rubber is added to the bituminous mass. Due to this, the mass changes its structure at the molecular level. Bituminous roofing made of the material has higher flexibility and strength at sub-zero temperatures, and also acquires the ability to repeat all surface bends and return to its original state even after significant stretching.
- APP. This is the name of the mixture to which the polymer (atactic polypropylene) is added. Due to this, the finished fabric changes its plasticity with temperature changes (the higher the temperature, the higher the plasticity and vice versa). The added polymer has a low cost. Therefore, the bituminous roof obtained with its use costs less than with SBS additives.
Advantages and features of modified coatings
SBS modified material:
- It has a high coefficient of elongation - the canvas can be stretched to a length greater than the original 20 times, and at the same time it will not collapse, but remain intact. For oxidized bitumen, this figure is much lower.
- At temperatures below zero, the canvas retainsflexibility and elasticity.
- When folded, the canvas does not crack, even if the ambient temperature is below zero.
APP modified material:
- Changes plasticity with temperature. The higher the thermometer, the faster the plasticity improves, and vice versa - with a decrease in temperature, the flexibility of the coating sharply decreases.
- The cost of coverage based on AMS modifiers has a lower cost than the SBS counterpart.
Disadvantages of modified roofing
APC coating is not intended for use in regions where winter temperatures drop below -25 degrees. It starts to crack and crumble. When applying a coating to the roof, it is necessary to work with it carefully. The material is completely inelastic, and if stretched, it does not return to its original state.
Due to the variety of roofing bituminous materials on the construction market, each consumer can choose the option at the most suitable price and with the characteristics that suit him.
