Main image: Knauf Insulation DriTherm Slab

South Africa’s energy crisis means homeowners have experienced cold, dark nights this winter. To address this, the Part XA update to SANS-10400 has brought in sweeping reforms to increase building energy efficiency, but there is a strong case for going beyond the legislation.

Setting targets for thermal performance

Part XA sets targets for the thermal performance (the R-value) of each construction element, depending on the building’s location. For zones 1, 2, 4, 6 and 7, this target requires a minimum 50mm cavity for concrete and brick external masonry walls. The best way to achieve maximum energy performance is by adding a cavity and fill it with insulation.

The importance of insulation

Research by the Clay Brick Association and the University of Pretoria found that adding a cavity reduces energy consumption by 30%. Filling that cavity with insulation reduces it by 70% – thus lowering fuel bills and energy demand.

Mineral Wool insulation adapts to minor imperfections in the substrate, friction fits between building elements and knits together at the joints to prevent gaps.

Knauf Insulation’s DriTherm® Masonry Cavity Slab 37 is manufactured from glass mineral wool and is designed to be installed in external masonry cavity walls during construction. It has an R-value of between 1,40Wm2K and 4,41Wm2K, depending on the thickness, and creates a stable and comfortable indoor environment, whilst being more environmentally friendly.

It is non-combustible, with A1 Euroclass reaction to fire classification, and does not add to the development or spread of fire nor create toxic fumes or gases.

Manufactured slabs

Slabs are manufactured in 455mm widths to suit standard wall tie spacing and with Knauf Insulation’s unique bio-based binder, ECOSE® Technology, for improved handling and installation. It contains no added formaldehyde or phenol and is 70% less energy-intensive to manufacture than traditional binder, so it is more environmentally friendly.

For more information, contact Knauf Insulation:
Tel: +27 74 512 7817

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