How can a bar be strengthened

A roof beam reinforcement saves the replacement

How do you strengthen roof beams?

There are several occasions to reinforce the roof beams of a building. The need usually arises from a different use of the building. If, for example, the attic is to be expanded or a solar system is to be installed on the roof, existing components can be overloaded. Even if the roof beam has cracks, renovation is often the only solution.

The most cost-effective measure here is to reinforce the roof beams. It is a technically safe measure that does not require any major interventions in the building fabric. The existing framework, which is too weak, can still be used.

What types of load capacity increase are there?

Side reinforcement

It can be done using wood or steel components screwed on on both sides. The connection of the reinforcement components to one another is mainly carried out with dowels and screws.

Reinforcement on the top

It is the most classic method for renovating roof beams. The connection relies on fully threaded screws that are screwed in either perpendicular to the direction of the wood grain or at an angle to it.

Reinforcement on the underside

Reinforcement on the underside is rather rare, as the ceiling below would have to be exposed. This is not a problem with steel profiles to reinforce the roof beam. The folded profile is very stable and is screwed on from below.

Side reinforcementWooden straps or steel profilesDowels and bolts, dowels, screws
Reinforcement on the topDouble a wooden beamConnection by screwing or toothing
Reinforcement on the undersideSteel profiles or steel sheetsScrews

Alternative to conventional reinforcement methods

Newer methods of reinforcement at the top make use of a wood-concrete composite construction. A structural reinforcement with polymer concrete was developed in a research project by the Bauhaus University Weimar and Bennert GmbH.

A slightly higher formwork on the side is attached to the existing structure. The resulting cavity above the ceiling joist is then filled with a polymer concrete layer.

This procedure has many advantages:

  • warped roof beams are given a flat surface
  • low construction heights
  • light weight
  • no slippage, as there is a rigid bond
If damage caused by moisture to the roof beams in the area of ​​the supports is discovered during renovation, a building expert should clarify whether such a beam can be reinforced with wood or steel.
Article image: J. Marquardt / Shutterstock
Start »Build» Roof »Roof truss» Wooden beams