Asphalt felt or felt roofing is still often used when referring to bitumen membrane or bitumen roofing. The support layer of the waterproofing material is no longer ‘felt', but more commonly polyester or glass fibre. Also, so-called blown bitumen has been replaced by modified bitumen. SBS-modified rubber bitumen is most appropriate for the Finnish climate. In this product, SBS-elastomer is added to the bitumen mass. This way the rubber bitumen membrane becomes more flexible: it easily returns to its original form after temperature changes and is more UV-resistant than previous products.
Waterproofing of a new building or renovation of an old roof will be successful when using safe and high-quality bitumen membranes and skilled installation engineers.
In Finland, waterproofing is based on regulations and standards. Varsinaisbitumi Oy only offers certified material for contracting.
In our line of business, unclassified bitumen products are only used at the client's request. Moreover, different manufacturers and importers have their own classification codes and product names. In connection with waterproofing, however, the product categories of the VTT Technical Research Centre of Finland mostly apply.
The client, the housing manager and the supervisor should know to what extent the product description and the code of the material match certificates and standards. It is in the interests of both the contractor and the client that the request for an offer, the offer, the bid competition, the negotiations, the execution of the order and quality control are comparable with regards to content.
Varsinaisbitumi Oy uses VTT-certified Eurogum bitumen products in waterproofing contracts. VTT certificate (N:r 187/04).
Modified bitumen membranes are divided into four product categories - TL 1, TL 2, TL 3 and TL 4. These categories meet different criteria. (The National Building Code of Finland C2 Moisture, Regulations and Guidelines 1998 and E1 Structural Fire Safety in Buildings, Regulations and Guidelines 2002)
In the planning and realisation of waterproofing, we base our material choices on the regulations and guidelines of the National Building Code of Finland, such as VTT SERT R005/01, Toimivat katot (functioning roofs) 2006 (Kattoliitto (Finnish Roof Association), RIL 107-2000, Rakennusten veden- ja kosteudeneristysohjeet (guidelines for water and moisture isolation) (Rakennusinsinööriliitto) (RIL Finnish Association of Civil Engineers). Varsinaisbitumi Oy gives advice on the choices of material for different applications.
|Product||Product category||Roll size||Support layer||Attachment to base||Areas of use|
|TL2||8m x 1m||polyester||welding||surface membrane in multi-layer covers|
|10m x 1m
10m x 1m
20m x 1m
in multi-layer covers
Eurogum Mono 5500 FR
|TL1||8m x 1m||polyester||welding
For more detailed information on products, categories and certificates, please contact Varsinaisbitumi Oy.