Know-how

The wood

Preservation of timber frames

Wood frames in older buildings often suffer from bad ventilation under the plaster stucco, resulting in structures devastated by micro-organisms and infiltration.

After stripping the damaged areas, glass fibre connectors are sealed into the parts of wood in good condition using resin in order to ensure the continuity of the structures between the preserved parts and the parts reconstituted using RENOFORS BOIS resin mortar (epoxy resin mortar formulated for wooden structures).

This type of reinforcement is rot-proof; it does not generate a dew point when in contact with the preserved wood. Its deformability is very close to that of the wood substrate, thus limiting the risk of any debonding between the preserved wood and the resin mortar reinforcement.

Restoration of beam ends

Beam ends sealed in masonry end up rotting subsequent to roof infiltration, capillary absorption through stucco, masonry, or stone bond. Metal or wood crosspieces are often installed to restore the beam's support on the bearing wall without taking into account differences in elasticity between wood and metal (aside from parameters related to the architecture), nor the risk of condensation at the interface between wood and metal (thermal inertia).

Conventionally, the pure and simple replacement of the floor beams or large span carpentry elements are to be considered.

After having propped the structure up, and with the beam's deteriorated end eliminated, Renofors places glass fibre composite pins sealed with resin in the wood remaining in good condition and restores the beam end around these age-resistant and chemically inert rebars using a stained RENOFORS BOIS resin mortar which is poured in place in a structured formwork.

There is no risk for condensation at the interface of the wood-resin bond, no exposed reinforcement and the beam regains a continuous wood look after sanding and glazing.

This repairing technique does not require any major dismantling of structural elements, thus allowing for shorter completion times.

Split repair

Some old beams sometimes have inappropriately placed knots, checks, or deformations due to excessive permanent and/or operational live loads and end up breaking.

After propping and raising up the beams, Renofors drills holes or rabbets in which glass fibre or carbon rebars are embedded to take up the bending stresses.

These rebars are sealed using resin, which can either be glazed or dressed with wood splines masking their presence and ensuring the continuity and homogeneity of the facing.

Stitching and pinning of wood structures

Wood structures, such as carpentry, belfries, various tenon and mortise assemblies get loosen or break.

Without dismantling the wooden structure, once it has been realigned, pinning can be carried out to ensure the structural continuity using composite rebars sealed with resin.

This method can also be used to stitch bearing elements that have detrimental checks running across them.

Reinforcement of beams from extrados

This process concerns all reinforcement work on conventional wood floors.

It is implemented according to the destination of the premises and is particularly suitable for buildings open to the public during rehabilitation of old buildings (museums, meeting rooms, archives, libraries, galleries, etc.), whose purpose changes or when considerable standard live loads must be applied.

If the depth of the floor allows for it, it is possible to provide additional inertia, and hence a greater bearing capacity to the beams by pouring compression tables made of RENOFORS BOIS resin concrete over them.

These compression table reinforcements are connected to the beam from above along a gluing surface and with joining rebars laid out in gains intended to take up the tangential stresses at the interface between the beam and the reinforcement footing.

Reinforcement of beams from intrados

To increase a beam's inertia and consequently its bearing capacity:
A wood prosthesis can be consolidated with the beam's soffit using RENOFORS BOIS resin and also be linked to the existing beam using glass fibre composite rods.

REBOFIL and multi-ply light self-supporting flooring systems

In old constructions, these systems enable the installation of floors supporting heavier loads than the existing structure, without overloading the original beams, nor adding any humidity as would be the case with concrete slab systems connected to the wood beams.

Multi-ply flooring systems, panels of laminated wood slats, as well as laminated and tongued-and-grooved REBOFIL boards are available in various widths and thicknesses (providing the mechanical inertia) to build light bearing wood floors between joists or major supports. They are dry (no added humidity), reversible, and do not require any strutting of the floors to be reinforced.

Moreover, the REBOFIL system can be left exposed. It can also be sanded and stained to use it directly as a hardwood floor or as an exposed ceiling. These wood board systems provide natural soundproofing