Shopping Cart

Order total 0€
SPECIFICATIONS AND CATEGORIES OF BITUMINOUS MATERIALS

Bituminous membranes (bituminous sheets) are the major material for waterproofing external surfaces. It is a material which can offer excellent sealing results in case of a combination of correct application and selection of high-quality membranes is achieved.

Bituminous membranes (bituminous sheets) are the major material for waterproofing external surfaces. It is a material which can offer excellent sealing results in case of a combination of correct application and selection of high-quality membranes is achieved.

From the name it is clear that the main raw material used in the construction of an asphalt sheet is bitumen. The bitumen used for the production of asphalt sheets may be oxidized bitumen or modified bitumen. In particular:

OXIDISED BITUMEN

Oxidized bitumen (OXY) is the first attempt to improve bitumen by oxidation in order to increase the useful temperature range. Its main disadvantages are sensitivity to UV radiation, low resistance to low temperatures and short life due to ageing of the mixture.

In conclusion, it is not recommended to apply bituminous asphalt on the surface to be waterproofed, especially if waterproofing is the final stage of insulation.

MODIFIED BITUMEN

Bitumen is known for its ability to prevent water infiltration. However, it needs to be modified in order to better withstand temperature changes and drying and to maintain its elasticity even at low temperatures. It is divided into two types:

  • Plastomeric: Asphalt can be more plastic by adding APP (unconformable prolypropylamine).
  • Elastomeric: Bitumen can be more elastic by adding SBS (styrene-butadiene-styrene) polymers.

In conclusion, these asphalts (APP & SBS) are the ones to be chosen for sealing a surface because they offer a higher degree of elasticity and durability than those of oxidized asphalt.

The main differences between APP & SBS asphalt sheets are the degree of elasticity (plastomeric and elastomeric) and resistance to low temperatures of the outdoor environment (APP can withstand up to -10 degrees Celsius while SBS can withstand up to -25 degrees Celsius without specific temperature ranges being binding).

Useful Tip: When waterproofing an area of more than 200m2 choose SBS bituminous screeds instead of APP due to the high degree of stresses due to substrate contraction.

ATTENTION: It has been observed the phenomenon where various garages and craftsmen, in order to make their offer more attractive, propose bituminous screeds with aluminium coating, without mentioning its type and quality. Thus, on the one hand, in order to be competitive on the market and, on the other hand, because elastomeric bituminous foams with an aluminum coating are very expensive, they apply those of oxidised bitumen.

 In addition to the main material of construction (bitumen), bituminous sheets are divided into categories according to their reinforcement, their weight per square metre and the coating material on the upper part of the membrane.

REINFORCEMENT OF ASPHALT SHEETS

The reinforcement of asphalt sheets is a very important element in terms of quality and resistance (to puncturing, tearing, etc.) and the general performance of the waterproofing. The reinforcement of asphalt membranes is mainly divided into the following categories:

  • Glass reinforcement
  • Glass fibre reinforcement
  • Non-woven polyester

Useful tip: For better durability and performance, prefer bituminous membranes with reinforcement of the third category.

ATTENTION: In addition to the type, check the weight of the reinforcement. Third class bituminous felts may have reinforcement weights from 100gr/m2 to 160-180gr/m2 with the corresponding gradations in both quality and price.

COATING & WEIGHT OF BITUMINOUS SHEETS

Tar papers in terms of weight and thickness range from 2.5kg/m2 to 6kg/m2 with thicknesses from 1.5mm to 5mm.

Depending on the use of the membrane, the top coating can be:

  • polyethylene film or sand
  • colored mosaic
  • Metal sheet (aluminum or copper)

Useful tip: When waterproofing a roof is implemented with a single layer of bituminous membrane, it is preferable that the weight of the membrane is at least 5kg/m2. If you can afford it, choose without a second thought the waterproofing with a double layer of bitumen, because research has shown that single layers of bitumen have twice the injury rate of double layers.

Are you ready for the next step?

Insulation - Thermal insulation - Waterproofing

Cookies are necessary for the proper functioning of monodomiki.gr and for enriching your online experience.
Please choose «Accept» or «Settings» to set your preferences.
Necessary Cookies
The minimum required cookies for this site to function and cannot be disabled. These cookies are not tracking cookies. If you configure your browser to block or disable the use of these cookies, this site or parts of it will not work properly.
Statistics

Statistics cookies allow us to evaluate various aspects of this site in order to improve it and offer you the best possible experience.

The tools used for statistical analysis include Google Analytics, Hotjar, Kelkoo sales tracking, Facebook Pixel, Pinterest Tag.

Miscellaneous

These cookies are used by third party tools in order to implement additional functionality in our site, such as Google Maps, Social/Sharing buttons etc.