CalciumSilicate
Purely mineral and inorganic insulating material born from lime, siliceous sand and water autoclaved together. Extraordinary for its active nature: not a barrier but a micro-capillary sponge able to absorb large amounts of moisture and then release it, providing failsafe internal thermal insulation against mould in listed buildings (Green Homes Directive).
Internal Insulation. A conventional plastic insulator would create a weeping wall by condensing water between itself and the cold masonry. Calcium silicate breathes, absorbing moisture and releasing it back when the air is drier.
With the EU Green Homes Directive, millions of historic masonry buildings must be energy-retrofitted. Unable to install external insulation, building physics collides with the danger of interstitial condensation. The Calcium Silicate board is the only engineered answer to insulating the interior without causing rot.
Insulating an old brick wall from the inside with polystyrene or polyurethane creates a perfect trap. Moisture in the old wall can no longer dry towards the room interior. This causes inevitable liquid condensation between the insulator and the cold masonry, triggering devastating black mould and plaster disintegration.
Calcium Silicate is a massive micro-porous board (over 90% of its volume is interconnected micro-pores). It does not block vapour, it manages it (diffusion-open insulation). During humidity peaks, the board acts as a hydraulic buffer, rapidly absorbing condensation into its micro-capillaries and spreading it over a large area. As soon as the air dries, the board breathes, releasing moisture as invisible vapour.
Standards
European and international references applicable.
Physical properties
Usage environment
FULL-BED BONDING: there must be no air behind the panel. If adhesive is applied in dabs (as in EPS external insulation), warm air infiltrates the gap and condenses on the cold wall. Silicate adhesive must be spread over the entire slab (100% full-bed). NO GYPSUM: gypsum-based plaster or acrylic paints close the pores, blocking evaporation. Use only silicate or natural hydraulic lime (NHL) mortars.
Documented applications
TAV. DHistoric Centre Retrofit
Green Homes energy retrofit for historic buildings untouchable on the outside. Bonded directly onto sound existing plaster.
Mould and Thermal Bridge Remediation
Definitive resolution of black walls (north-facing) in 1970s bedrooms caused by poor ventilation and over-airtight windows.
Basements and Habitable Cellars
Panels to line below-grade walls. Capillarity manages mild rising damp, drying and dehumidifying the basement air.
Passive Fire Protection
Thanks to non-combustibility (Class A1), thin boards are used to line technical shafts and protect metal structures.
Vapour Diffusion Resistance (mu — lower = more breathable)
TAV. EA mu value of 3 means the calcium silicate panel opposes moisture passage with only 3 times the resistance of free air. It is essentially transparent to water vapour, preventing any destructive interstitial stagnation.
Used in these systems
TAV. SReference regulations
1 normInformational links to the regulatory framework. Always verify the current text on the official source.
Operational documents from this sheet
Specification clauses, site checklists and compliance dossiers generated from the graph — and kept in sync when a cited norm changes. Join the waiting list.
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