HOW TO PLACE XPS BOARDS: FROM CUTTING TO FINISHING

XPS insulation has many advantages , such as being lightweight and therefore easy to work with.. In this article, we address questions such as “how do you cut an XPS board”, “is XPS foam safe to cut”, “how to attach XPS boards”, “what is the best glue for XPS foam”, “how to finish XPS” and “can you paint XPS”. HOW TO CUT XPS FOAM XPS insulation boards come in various dimensions and are easy to cut. The simplest way to cut XPS foam straight and cleanly is to use a saw. ● CUTTING XPS FOAM WITH A HOT WIRE? Another option is to cut XPS foam using a hot wire. This cutting technique is widely applied in secondary manufacturing processes where close-tolerance finishes are required. ● IS XPS FOAM SAFE TO CUT? XPS foam is completely safe to cut – unlike some other insulation products, which can cause temporary irritation of the eyes, itching and redness of the skin. HOW TO PLACE XPS BOARDS When XPS boards are placed horizontally, for instance in an inverted roof or floor, they are typically loose laid. In an inverted roof application, the XPS boards are kept in place by ballast such as gravel, while tiles or other layers make sure the XPS insulation stays put when used in floors. Used vertically, in walls such as cavity walls, XPS insulation boards are mechanically fixed, like other insulation boards. ● WHAT IS THE BEST GLUE FOR XPS FOAM? If you prefer to glue your XPS insulation, PU or MS polymer-based adhesives are the best choice. Solvent-based glues are not suitable, because they may dissolve the XPS foam. It is always a good idea to test the adhesive on a piece of XPS insulation board first. ● XPS BOARDS: GLUEING TO CONCRETE? XPS boards can be glued to concrete, provided you select the right glue, i.e., a PU or MS polymer-based adhesive. ● XPS GLUEING TO BITUMEN? XPS insulation boards can be glued to bitumen used in foundations (below-ground). ● GLUEING XPS FOAM TO WOOD? It is possible to glue XPS insulation boards to wood, though not with solvent-based glues, as they will dissolve the XPS foam. Try a test piece to make sure your glue is compatible with XPS. HOW TO FINISH XPS There are various ways to finish XPS, depending on the application. On inverted roofs, ballast like gravel or tiles is placed on top of the insulation board. In cavity walls, XPS boards can be finished with every type of brick. On the inside, walls with XPS can be plastered, given that you opt for XPS boards with a rougher finishing such as a wafer finish. On the outside, XPS insulation boards can be finished with wood that is mechanically fixed to a structure. There is no finish needed in underground applications, because XPS has excellent water vapour diffusion resistance. While EPS has a water vapour diffusion resistance of 30-70, XPS reaches 80-250. Nevertheless, to make extra sure when insulating an inhabited area, you can place a PROTECDRAIN FILTRE in front of the XPS insulation. ● CAN YOU PAINT XPS? Just like your glue needs to be compatible with the XPS foam, the paint you use on XPS boards cannot be solvent-based to prevent the insulation foam from dissolving. A safe workaround is to opt for insulation boards to which you can apply ALSAN liquid waterproofing, which is available in any RAL colour you want. ● CAN I USE XPS BOARDS UNDER TILES? It is perfectly fine to use XPS boards under tiles. This is, in fact, the most common scenario when using XPS insulation for floors or in inverted roof applications. OUR XPS EXPERTS ARE THERE FOR YOU Don’t hesitate to reach out to our experts with any additional questions you may have.

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