How and where to use guide
EARTHWOOL GLASS MINERAL WOOL DRITHERM CAVITY SLAB 32 ULTIMATE 1200 X 455 X 150mm (4) - 2.184mtr sq
Typical applications
Dritherm Cavity Slab 32 Ultimate is primarily used in cavity wall construction where the cavity width accommodates 150mm insulation. It is suitable for new build residential and commercial masonry projects, as well as renovation work where cavity width permits. The product performs well in both exposed and sheltered locations, providing consistent thermal performance across varying UK climate conditions.
- New build cavity wall construction with masonry inner and outer leaves
- Renovation and refurbishment of existing cavity walls
- Residential and light commercial applications
- Projects requiring enhanced thermal performance to meet Building Regulations Part L
Installation and fixing
Slabs must be installed as the outer leaf is built, pushing them firmly into the cavity to ensure full contact with the inner leaf. Each slab should be supported on cavity wall ties or friction fit within the cavity. Ensure slabs are cut cleanly to fit around openings such as windows and doors, with no gaps left unfilled. Stagger joints between slabs to avoid continuous vertical lines. The product should not be compressed or over-tightened, as this reduces thermal performance.
- Install slabs during masonry construction as outer leaf is built
- Push firmly into cavity for full contact with inner leaf
- Support on cavity wall ties or friction fit as appropriate
- Cut neatly around windows, doors and service penetrations
- Stagger vertical joints between adjacent slabs
- Do not compress or force fit slabs into undersized cavities
Cavity width and ventilation
Verify cavity width before ordering to ensure 150mm slabs fit correctly. Maintain minimum cavity width requirements for ventilation and moisture management. Ensure cavity remains clear of mortar droppings and debris that could bridge the insulation and create thermal cold spots. Where cavities are narrower than 150mm, a thinner product should be selected. Ventilation paths must not be blocked by insulation placement.
- Confirm cavity width accommodates 150mm insulation thickness
- Keep cavity clear of mortar droppings during construction
- Do not use in cavities narrower than 150mm
- Maintain ventilation requirements as per Building Regulations
Limitations and site considerations
This product is not suitable for exposed applications where it would be subject to weather or moisture ingress. Do not use below ground level or in areas prone to water penetration. The slabs are rigid and cannot be compressed to fit undersized cavities. Protect from rain and damp conditions on site before installation. Handle carefully to avoid damage to edges and faces, as damaged areas reduce thermal performance. The product must be installed in accordance with Building Regulations and relevant British Standards for cavity wall construction.
- Not suitable for exposed or external use
- Do not install in cavities subject to water ingress or below ground
- Protect from rain and moisture during storage and installation
- Handle carefully to prevent edge and face damage
- Install in compliance with Building Regulations Part L and relevant standards