Underlay membranes

An underlay is an essential part of the roof construction

Special attention should be paid to the selection of the underlay, particularly with discontinuous roofing (tile, tin etc.) which are not waterproof. There are many types of underlay available and it is not immaterial which one you choose. The lightest solution to lay under a tin or tile roof is a plastic hanging underlay, whereas the sturdiest and most compact alternative is a solid wood decking and an underlaymembrane laid on top. 

Tuoteryhmäkuva-aluskatteet
Feature Kerabit
Protect
Kerabit
Super
Kerabit
700 UB
Kerabit
1800 UB
Fleece
Kerabit
2200 UB
Kerabit
2400 UB
Kerabit
2600 UB
Fleece
Kerabit
3000 UB
Underlay classification - AKV 1 AKV 1,
AKK 1
AKE,
AKK 1, TL 2
AKK 2 TL 3,
AKK 1, AKE
TL 2, AKE,
AKK 1
TL 2, AKE,
AKK 1
Basis weight, g 130 210 700 1800 2200 2400 2600 3000
Bitumen underlay     x x x x x x
Plastic underlay x x            
Roll size 1,5 x 50 m 1,5 x 50 m 1 x 30 m 1 x 15 m 1 x 15 m 1 x 10 m 1 x 10 m 1 x 10 m
Potential coverage per roll  63,75 m2 63,75 m2 25,5 m2 13,3 m2 12,7 m2 8,8 m2 8,8 m2 8,8 m2
Reinforcement layer material Poly-
propylene
Poly-
propylene
Poly-
ester
Polyester Fibre-
glass
Reinforced
polyester
Reinforced
polyester
Reinforced
polyester
Diffusion-open x x            
Adhesive edge   x x x x x x x
Hanging installation x x x          
Fixed installation     x x x x x x
Step resistant
as hanging
  x x          
Under bitumen roofing     x x x x x x
Under tile roofing x x x x x x x x
Under tin roofing x x x x x x x x
Sand on surface         x x   x
Roofing to be installed within
one
month
within
one
month
within
one
month
When
necessary
after
winter
within
one
month
When
necessary
after
winter
When
necessary
after
winter
When
necessary
after
winter
 * If you install an underlay membrane late in the autumn, we recommend that you choose Kerabit 2400 UB or 3000 UB, whereby the end result is better and more durable. In such a case, you can install the surface roofing of a high-pitched roof in the spring when the weather is warmer. 

Kerabit 2200 UB

An underlay with adhesive edge to be used under bitumen shingles, for example.

Kerabit 2400 UB

An underlay with adhesive edge to go under bitumen shingles, for example. The carrier consists of polyester.

Kerabit 2500 UB

An underlay with adhesive edge to go under bitumen shingles, for example. The carrier consists of polyester.

Kerabit 3000 UB

An underlay with adhesive edge to go under tile and tin roofings. The carrier consists of strong polyester.

Kerabit 700 UB

A bituminous underlay, that can be installed either on solid wood underlays or as a hanging underlay.

Kerabit 1800 UB Fleece

A modified bitumen underlay membrane for discontinuous roofings.

Kerabit 2600 UB Fleece

A modified bitumen underlay membrane for discontinuous roofings.

Kerabit Protect

A diffusion-open underlay, that can be installed directly on the surface of thermal insulation.

Kerabit Super

A diffusion-open, product classified waterproof underlay with adhesive edge.