REINFORCING FIBREGLASS RENDER MESH

Reinforcing mesh also called ‘fibreglass K-rend mesh’ is a flexible, flat pressed lattice made from special woven glass-fibre strands offering incredible strength when embedded into wet basecoat plaster or render. Fibreglass Mesh is an essential component of all render systems. It is ideal for reinforcing render, particularly around openings or areas of traditional weakness. It can be used to stabilise unstable surfaces, cover and help prevent cracking. A part of performing this reinforcing layer is strengthening edges of the insulation layer - corners, areas near windows and doors etc. These are the areas where stress is concentrated and may be subject to cracking if sufficient strength is not provided. Mesh is alkali-resistant. This helps prevent it being broken down by the chemicals in the other mortars and adhesive materials. 

TYPES OF REINFORCING FIBREGLASS MESH | SIZES | PRICE

All rolls come in standard size 1m x 50m or 1m x  55m. There are 50m2/55m2 of mesh per roll. One of the most important parameters of the reinforcing mesh is its surface mass - the weight of the material with an area of a square meter. This parameter is given in grams per square meter and is most often in the range from 130 to 210g/ m2. Generally speaking - the higher the number, the stronger the mesh. However, it is not recommended to use façade meshes with values above 165g/m2 as they would be too stiff. Heavy mesh detaches from the wall when applied with adhesive. When buying a facade mesh, it is also worth paying attention to the mesh dimensions and the quality of the weave. The most commonly used is the so-called Gauze weave, which is characterized by high stability. However, this does not adversely affect the flexibility of the mesh, which is still high. Second type is called Raschel mesh - created by cross – arranging straight, linen fibers. Typically, this weave is used in places that are characterized by a small load of wall and ceiling movements.
Reinforcement mesh are lightweight, usually 9.5kg, therefore assembly is not difficult and does not take much time. Facade meshes also differ in terms of mesh size. When selecting the mesh, it is important to pay attention to the mesh size and regularity. A good ‘net’ should have regular mesh sizes. This ensures dimensional stability and facilitates the embedding of the mesh. Depending on the grade they can be found in 130g/m2 ,160g/m2 and 210g/m2 . Reinforcing mesh can be supplied in 2 different grades (mesh aperture). One for internal use and second for exterior use. While grades 3mm x 3.5mm, 5mm x 5mm and 9.5mm x 9.5mm are used to reinforce external wall insulation and rendered rainscreen cladding systems, 5mmx5mm are used to reinforce gypsum plasters and cover internal wall slits up to 50cm in width. Most of the meshes come with markings 100mm from each end – this marking illustrates the overlap of the mesh required when installing it. Standard houses in England need 2-3 reinforced rolls, which gives about 100-150 m2 of coverage.The cost of buying reinforcing mesh for 150m2 of external wall insulation is £210.42 ex VAT(3 rolls).

REINFORCING MESH INSTALLATION

Within both render systems and external wall insulation systems, the fibreglass mesh is embedded within the basecoat layer. The mesh needs to be embedded within the basecoat while it is still wet. It is recommended getting the mesh embedded within the middle of the layer of the basecoat, rather than too close to the surface. The mesh should be installed with overlaps of approx. 10 cm. It should be remembered that the thickness of the adhesive with one layer of mesh should not exceed 8mm. It is optimal when it is about 5mm. Best way is to pull down the mesh and melt it into the adhesive. Do this by squeezing out the adhesive from the center of the mesh strip. If everything goes as it should, the mesh will sink into the adhesive without folds along its entire thickness. Embed the next strips of the concealed mesh with the "overlap" method, which should be at least 100mm. Ensure the first pass of the basecoat has not dried before applying the second pass of mesh.

Video credit:https://www.youtube.com/watch?v=N1juCG6adcI&t=206s