The TB-Trough is used instead of the traditional solution with roofing felt, in order to prevent the driving rain getting in through window and door openings on the front.


The TB-Trough makes possible to place the wire tie anywhere.
By using a TB-Trough instead of masonry paper, the strength of the brick beam is enhanced. In the example below, the calculated height of the 3-layer brick beam is elevated by 2 layers.


The improved strength above wall openings doesn't influence the mounting. The TB-Trough is quite quick and easy to mount.




By using TB-Trough, it's possible to calculate for a theoretical reduction of 10 % of the wall thickness by the beam's height = wall height. This means that the load capacity for a brick beam is calculated by H = wall height, but the actual wall thickness is reduced by 10 %. Thus, there are great practical advantages in contrast to current practice, if the beams' height doesn't need to be calculated as higher than the embedded wall paper.




The TB-Trough is inserted on the back side of the façade, where it can be embedded through the 2nd and the 3rd layers. It's recommended to bond the TB-Trough with suitable adhesive, i. e. asphalt glue. The glue is spread between the brick surface and the solid part of the perforated mounted edge of the hinge (Trough). The glue is spread between the back side of the brick and the horizontal edge of the hinge (Trough).


The TB-Trough's functionality depends on the correct mounting. It's important that there aren't any cold bridges between the front and the back-up lintels.

Montering af TB-rende

When mounting the TB-Trough, please note: ​

  • During bricking in, watch out that the water doesn't run behind the TB-Trough, through the holes, in the bricked in edge. This is prevented if this edge is completely covered in mortar, while the joint is compressed.
  • The insulation must be adjusted to fit the TB-Trough exactly, and it's important that no residue from the insulation remains in the hinge (Trough).
  • The TB-Trough is mounted on each side in relation to the light opening, with a min. of 20 cm over length.
  • The TB-Trough's floor must be cleaned of mortar in finished structures.


End fittings
If, because of limitations, for example in the case of ”small window division bars” with TB-Trough on both sides, or for example on corner windows, penetrating water can't be diverted to the back side of the front wall, an end fitting is mounted. If no special precautions need to be taken, it is recommended that you mount the end fitting only at one end, so that the drain on the other side is free.


The end fittings must be glued to the ends of the TB-Trough. The gluing must be performed at temperatures of above 5° C.
The supplied pipe is mounted with the respective plastic clip on the draining nozzle of the end fitting, and is fed towards the exterior through the façade joint. The pipe needs to be 1 cm from the front wall and must not have a reflux.


Pipes need to be inspected once a year and if necessary blown clean with an air pump.




The difference between a TB-Trough and masonry paper is obvious looking at the calculation of the strength in a composed brick beam. The TB-Trough also makes it possible to place the wire tie anywhere.


With the TB-Trough, the existing layers may be factored into the strength, which cannot be done when using masonry paper.
The TB-Trough has small ”feet” that grip the masonry and do not allow any ”breakage”, as opposed to what may happen with masonry paper.


TB-Trough (Hinge)
Every layer is included in the strength calculation, but because of the TB-Trough, for each layer one must deduct 10 % of the thickness.
1 layer by 108 mm bricks/10% in width = 97 mm.
In other words, in this case a load capacity is determined that corresponds to 6 layers at 97 mm each.


Masonry paper​
The load capacity lies only in the lowest 3 layers with full strength (100 %), as the top 3 layers aren't counted.
The masonry paper breaks the cohesion of masonry where it is walled in.
This means that in this case there is a load capacity that corresponds to 3 layers at 108 mm each.

Montering af TB-rende



By using TB-Troughs, the load capacity for a brick beam with H = wall height may be calculated, where the thereby determined load capacity is reduced with 10 %. The height can be calculated, however, no higher than up to the lower edge of any supporting paper insert.


TB-Troughs and end fittings are made of recycled materials as far as possible. The TB-Trough is black, while the end fittings are white.


The TB-Trough and end fittings shouldn't be exposed to direct sunlight during storage. The adhesive must be kept at room temperature. 


End fittings
The end fittings are delivered as kits, which includes the following: 

  • 1 left end fitting
  • 1 right end fitting
  • 1 tube of adhesive
  • 50 cm transparent pipe (the length can be adjusted with a cutter)
  • 2 plastic clips


Standard lengths
The TB-Troughs are supplied in standard lengths, matching the brick lintels' length with 20 cm extra. The TB-Troughs may not be extended.


Reference lintel TB-Trough
Tile Length Length
4 stones 95 cm 115cm
5 stones 119 cm 139 cm
6 stones 143 cm 163 cm
7 stones 167 cm 187 cm
8 stones 191 cm 211 cm
9 stones 215 cm 235 cm
10 stones 239 cm 259 cm
11 stones 263 cm 283 cm
12 stones 287 cm 307 cm
14 stones 335 cm 355 cm
16 stones 383 cm 403 cm
20 stones 479 cm 499 cm
25 stones 599 cm 619 cm