Insulation for Masonry Overcladding
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These types of wall typically comprise an outer skin of masonry and an inner skin of lightweight steel frame (SFS) construction, although depending on building height the inner skin can also be of timber-framed or cross-laminated timber (CLT) construction. The SFS is typically filled with a mineral wool roll or slab, then finished internally with plasterboard and externally with a sheathing board to provide protection from the elements. Additionally, membranes such as a Vapour Control Layer (VCL), Air and Vapour Control Layer (AVCL) or a breather membrane may also be specified.
The insulation between the SFS alone is usually not enough to comply with Building Regulation thermal requirements, so additional insulation can be installed against the sheathing board and fixed in place with a brick channel & tie restraint system. Between the outer face of the sheathing insulation and the masonry outer leaf a minimum 50mm residual cavity is maintained.
The sheathing insulation is typically a stone mineral wool slab, such as Isover Polterm Max Plus and Isover Steel Frame Infill Batt can be installed into the SFS zone.
When using Celotex or ISOVER products, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions. In addition to the product datasheet, please refer to the following product documents:
- BBA certificates - where applicable to the application
- Declarations of Performance
- Health & safety datasheets
Celotex products should not be used in the external walls of buildings over 18 metres in height (England and Wales) or 11 metres in height (Scotland). Recent changes to Building Regulations mean that only non-combustible insulation or insulation of limited combustibility can be used in buildings of that height.
The building detail is for illustrative purposes only. It does not constitute advice and should not be relied upon.
|Product Name||Thickness Range||Sizes||Lambda|
|ISOVER Polterm Max Plus||50-200mm||Width 600mm, Length 1200mm||0.035 W/m.K|
|ISOVER Steel Frame Infill Batt||50-100mm||Width 600mm, Length 1200mm||0.036 W/m.K|