Work on historic buildings or old masonry requires particular care. The choice of plaster cannot simply fall on generic cement-based products. For this reason, the TecnoCanapa Bioedilizia® System offers Natural Lime Plaster (ICN). This is a plaster based on NHL 5 natural hydraulic lime, designed for the protection and breathable conservation of masonry, including Biomattone® walls.
What is Natural Lime Plaster (ICN)?
Natural Lime Plaster is a special plaster based on NHL 5 natural hydraulic lime. It is designed for the protection, repair and breathable conservation of masonry, including heterogeneous walls made of brick, tuff and natural stone. It is therefore suitable for filling and bonding coats, as well as for base coats and rustic finishes on new or old masonry, indoors or outdoors. Thanks to its properties and natural colour, it is particularly suitable for buildings of historic and artistic interest. Work of this kind often follows the conservation principles promoted by organisations such as ICOMOS, an international reference body for the protection of historic heritage.
Composition and characteristics of ICN
ICN is based on NHL 5 natural hydraulic lime. This binder provides high water-vapour permeability. In practice, this characteristic prevents moisture from becoming trapped in the masonry. This is a crucial consideration when working on old buildings, where traditional materials need to remain freely vapour-permeable. Thanks to its properties and natural colour, ICN is also suitable for environmentally compatible applications in contemporary sustainable construction.
Applications: conservation and sustainable construction
ICN can be applied both to heterogeneous historic masonry and to Biomattone® walls in the TecnoCanapa Bioedilizia® System. On a restoration site, for example, it can be used as a bonding coat and base plaster over stone or brick. In a new hemp-lime building, it protects masonry built with the blocks described in the complete Biomattone® range. In both cases, it preserves the wall’s vapour permeability.
Application: Natural Lime Plaster application data
Substrates to be plastered must be stable, clean and free from weak material. They must also be free from dust, salt efflorescence and residues from previous work. Where necessary, preliminary cleaning should be carried out using pressure washing or sandblasting. The product is supplied in 25 kg bags. Mix each bag with approximately 6.0–6.5 litres of clean water, adding the water to the mixer first and then the powder, until a homogeneous, lump-free mix is obtained. The prepared mix can be used within 3 hours of mixing. Apply by trowel at a thickness of between 10 and 20 mm per coat, or by mechanical spraying using plastering machines suitable for premixed products.
Natural Lime Plaster and the other finishes in the Biomattone® System
Once the base plaster has been applied, the wall can receive different finishes depending on the desired effect. For a fine smooth finish, products such as Malta Fine or Stabilitura Naturale Traspirante Plus are used. For a more textured appearance, Canapulino® or Canaposo® are selected. These finishes share the same hydraulic-lime base as ICN and the same focus on water-vapour permeability, so as not to compromise the comfort described in the hygrothermal comfort guide.
Frequently asked questions about Natural Lime Plaster
Is Natural Lime Plaster suitable only for historic buildings?
No. It is also frequently used on new Biomattone® masonry. Although it is designed for conservation work, its high water-vapour permeability is equally useful in new construction.
How long does the ICN mix remain workable?
The mix can be used within 3 hours of mixing with water. After this time, a new batch must be prepared.
What thickness can be applied in a single coat?
It is applied at a thickness of between 10 and 20 mm. Additional coats can be applied provided the previous coat has not yet dried completely.
In summary, Natural Lime Plaster combines the requirements of conservation work with those of sustainable hemp-lime construction. To explore the complete system, see the Biomattone® range and the product technical data sheets. You can also contact the TecnoCanapa Bioedilizia® team via the contact page for tailored advice.
