On pitched roofs, Laterlite lightweight expanded clay insulating products can be used to:
construct the loadbearing structure of a pitched roof slab or strengthen an existing one
In particular:
Levelling and regularising a supporting surface
Lightweight insulating semi-dry mortars (Latermix Facile, Latermix Fast) can be used to level and regularise steeply pitched or irregularly shaped surfaces.
They can be used on any type of pitched roof (of timber, steel, concrete, etc.) and can reduce loading by approximately 50% as compared to traditional methods.
For pitches of under 15%, ultra-lightweight semi-fluid Latermix Cem Mini concrete can be used.
The compact, closed structure of all these products makes them suitable to take directly applied waterproofing membranes, finishes, tiles, or insulated panels.
Improving thermal performance
Because of their reduced conductivity ? (lambda) and because they are denser than traditional insulating materials, lightweight mortars and concretes based on Laterlite expanded clay increase the thermal mass and the thermal inertia of a roof and attenuate summer overheating in the spaces below (better thermal lag, temperature damping, and periodic thermal transmittance). This is particularly beneficial in the case of lightweight roofs of timber or steel construction. They can also be used in association with other insulating materials for complete high-performance technical solutions.
Constructing or strengthening pitched roof slabs
The Latermix Beton range of premixed bagged lightweight insulating structural concretes can be used to construct the entire load-bearing part of a lightweight pitched slab (in concrete, or composite construction) or to strengthen an existing slab. This reduces structural loading by up to 40% as compared to traditional concrete (which is particularly useful in seismic zones to avoid overloading the building at the top) and reduces thermal bridging.
For further information please see the specific sections dealing with flat roofs, green roofs, or insulation for roof spaces.