Alkali Resistant Fiberglass Mesh Fabrics:basics
1. Fiberglass mesh fabrics are destined to reinforce plasters and renderings against tensile stresses.
2. They are built from glass yarns. FMF's quality strongly depends on yarn quality.
3. In order to withstand cement and lime alkalinity fiberglass mesh fabrics are immersed in an alkali resistant SBR solution or a solution of acrylic esters
4.Fiberglass mesh fabrics vary a lot by weight. Obviously heavier types possess better mechanical strengths.
5. Tensile strength is one of the most used criteria to distinguish among fiberglass mesh fabrics
6. Tensile strength after immersion in 50% NaOH solution for one month is another important criterion. This shows the effectiveness of the antialkaline protection.
7. Fiberglass mesh fabrics vary also a lot by mesh dimensions:
* 2x2mm FMFs (indicative type: Vertex R51) are used as elastomeric waterproofing layers reinforcements.
* 4x4mm heavy meshes (indicative type: Vertex R131) are used to reinforce EIFs.
* 5x5mm light meshes (indicative type: Vertex R52) are used to reinforce cementitious waterproofing products.
* 5x5 or 6x6mm meshes (indicative type: Vertex R86) are used to reinforce packaged gypsum and cement based renderings.
* finally 10x10mm to 12x12mm meshes (indicative types: Vertex R85, Vertex R93) are used to reinforce in situ cement renderings, mortars and screeds.
8. Colour of fiberglass mesh fabrics is just for aesthetic reasons. However if you try to sell in Greece 10x10mm FMFs of colours other than blue, then you are lost in advanc are lighter and more easy to work with than metal latsh products. Slowly but steadily they steal their market share.
10. Most producers recommend placing FMFs in the middle third of plaster thickness. There is no need for mechanical fixing. Just one layer of plaster, sinking of FMF in the plaster mass and then a second layer of plaster.
11. Overlaps of 10cm at least should be respected. Full attention to avoid creases is of utmost importance.
12.Fiberglass mesh fabrics are mainly used in:
- EIFS:Exterior Insulation and Finish Systems
- above insulating materials
- above wire channels
- diagonally above doors and windows
- to reinforce joints of heterogenous materials
- to increase impact, resistance etc.
13. In Europe there is an impressive increase in the yearly consumption of alkali resistant fiberglass mesh fabrics mainly due to the increase of EIFS apllications.
Chris Strogilis
http://maconwaterproofing.blogspot.com
About the Author:
Civil engineer with postgraduate studies in MBA and Marketing