TarFelt® – BS
Hessian Based Bituminous Waterproofing Membrane
TarFelt® – BS consists of a centre core of hessian adequately coated on both sides with oxidized bituminous compound. Mica / sand is then spread over on both faces to prevent inter-sticking of layers.
|Breaking Strength, kg, Min
|Heat Resistance at 68 ± 2 OC, 3 hr||No flow|
|Pressure Head Test at 300 mm height of water||No Leakage|
|Storage sticking at 55 ± 2 OC, 18 hr||No Sticking|
|Pliability up to 15 OC||No Crack||Water absorption, %, Maximum||2|
|Weight, kg, Min||35||Bitumen content per Roll, Kg||18|
TarFelt® – BS is recommended as an economical waterproofing system. It can be applied over various types of surfaces such as concrete, corrugated asbestos or GI sheet, timber, shell / folded plates, etc. It is also used for waterproofing of silos, grain godowns, warehouses, wagons, trams, buses, etc.
- Proven first generation waterproofing membrane and recommended for non critical over ground application.
- Economical with limited life.
- Dimensional stability with pliability to adopt to all contours.
- Specification regarding the nature of treatment should be decided depending on the type of structure and climatic conditions. For example, in severe climatic conditions, a heavy / extra heavy treatment should be adopted.
- Provide adequate number of drainage outlets of 100 mm diameter, at least for every 40 m2 of roof area.
- Clean the surface thoroughly to make it free from any foreign material. Repair all undulation and surface defect like cracks, honeycombing etc.
- PCC / Cementitius coving of 75 mm radius shall be provided at all junctions between vertical and horizontal faces.
- Apply a coat of ShaliTex Primer minimum @ 0.25 L / m2 and allow it to dry completely.
- Use STP Bitumen 85/25 as bonding material, which is to be prepared by heating it to the correct working temperature and spreading over the roof properly and uniformly @ 1.2 kg / m2 per coat for waterproofing application or as specified.
- Unroll and fix TarFelt® BS by applying uniform pressure with hand for removal of any entrapped air.
- Provide overlap joints of 75 mm in longitudinal direction and 100 mm in transverse direction of the TarFelt® BS roll and seal it properly with hot bitumen.
- Terminate TarFelt® BS at the top of parapet if the height of parapet is up to 450 mm. In case the height of the parapet is above 450 mm, terminate TarFelt® BS at parapet in a groove 75 mm x 65 mm at a height of 150 – 300 mm from the finished roof level and groove shall be filled up with cement-sand mortar (1:4) with addition of ShaliPlast LW+ @ 200 ml / bag of cement.
- Top coat shall be finished with a layer of stone grit or pea gravel (6 mm and down size) which shall be laid by spreading over a hot bitumen coat @ 1.2 Kg / m2 laid over the felt.
- In case of non-trafficable roof, over the finished coat of bitumen, apply a coat of SuperSilverShield, a bituminous based aluminium paint, @ 0.125 L / m2.
- For a trafficable roof, protect membrane with PCC / Tiles. In case of PCC, ShaliPolyFibre @ 600 grm/m3 and ShaliPlast LW+ / STP No 1 (Liquid) @ 200 ml/bag of cement to be added to improve the resistance to crack formation and as well as waterproofing properties of screed.
- Use ShaliBond BS/CS cold adhesive wherever hot application is difficult or not permitted.
- For multi-layer treatment, stagger all the joints.
Health & Safety
- Use goggles, hand gloves and shoes during application
- Clean hands with a mild solvent and thereafter wash with warm soap water
Available in 1 m x 20 m roll.
Keep in a cool dry place, under shed, away from heat. Do not stack more than three rolls in one column.