Bitumen Tar Based Roof Coverings

© – Welcome to Daniel’s Roof and our guide to bitumen roof coverings.

Bitumen based roof sheets are purchased in one metre wide rolls and are hot applied to the roof with a propane gas powered torch. This ensures a waterproof seal to the underlay felt. The top layer of felt can either be mineral finish or you can lay stone chippings to shield the material from the UV rays which can dry out the bitumen.

Bitumen is a by-product of the oil industry and is mixed with additives to improve flexibility and water tightness, the finished product is a weather resistant roll of felt which is laid as part of a system, usually onto new timber decking and an underlay felt. It is possible to lay directly onto existing felts but this is generally considered a poor approach as any faults or moisture will be sealed in.

This product is still very popular, as it is more flexible than fibreglass roof coverings.


Bitumen roof coveringsHere are the benefits of this system:

  • Trusted system that is fully compatible with existing or neighbouring roof sheets.
  • Cost effective – often cheaper than rubber roof sheets.
  • Easy to patch repair if needed.
  • Most flat roofing contractors will have experience in using this material.

Here is a list of known issues:

  • Fire risk as gas powered heat torch must be used.
  • Material will dry and crack if subjected to direct UV rays.
  • Either mineral finish top layer or a covering with stones must be used to protect against sunlight.
  • Thermal expansion often pulls apart joint and laps

Recommended Brands

Tecnatorch are the leaders in this field, the rolls of felt are widely considered to be the best in the industry. Superior adhesion and ease of torch are the trademark of Tecnatorch. It is also more difficult to “over kill” the torching of the bitumen when compared to other cheaper brands.

Baileys offer a slightly cheaper product which is similar to Tecnatorch. It doesn’t have the grooves on the back of the roll so the heating process may take slightly longer. Like the other brands this should be applied as a part of a system