Outline specification : plastering, rendering, masonry and pointing, tadelakt

Product Description

Unilit 30 is a traditional, dry premixed mineral stabilising mortar based on natural hydraulic lime as the binder and appropriate well-graded aggregates.

Unilit 30 is characterised by a slow but strong bonding, a high plasticity, a low content of soluble salts and an excellent water vapour permeability. The natural hydraulic lime mortar is inherently stable and designed to reduce problems of micro cracks along with premature drying out. Unilit 30 is perfectly water repellent and, hence, performs perfectly where rising damp and capillary action is prevalent. Furthermore, the natural pore structure of hydraulic lime gives Unilit 30 a high resistance against salt crystallisation.

The natural hydraulic lime binder, used to prepare the preblend, conforms to the European Standard EN 459-1, NHL 5 for building limes.  The mortar Unilit 30 conforms to the European Standard UNI EN 998-1.

Application Area

Unilit 30 is applied wherever, both from internally and externally, an important exposure to moisture and/or soluble salts is present. By the application of the stabilising mortar Unilit 30 the humidity present in the structure is seperated from the finishing layer to be applied, while its optimum vapour permeability allows humidity present in the wall to be able to rapidly migrate from the structure beneath. The seperation of the finishing layer from the humidity present in the structure stops the transport of soluble salts as well, which crystallise within the stabilising mortar layer.

Unilit 30 can be applied to damp walls of buildings and cellars, as a plinth or pointing, both internally and externally, for the protection of the structure against the effects of rising damp or as a protection of the background within humid environments, such as showers, saunas and hammams. Therefore, Unilit 30 is essential within the realisation of a tadelakt finish.

Unilit 30 can be applied as well for the stabilisation of salt loaden backgrounds.


Prior to application, the substrate must be cleaned and freed of all traces of oil and grease. The substrate benefits from being slightly dampened. Saturation of the substrate is not recommended, as this will influence negatively impact upon the bond of the hydraulic lime mortar to the substrate as well as the aesthetic appearence.

The mortar is mixed with clean water at a ratio of 5 to 6 litres of water to a bag of 30 kg ready mixed natural hydraulic lime powder. Mixing is undertaken with a slow speed electric paddle for a period of 4 to 5 minutes. A creamy workable mortar is obtained, which has approximately 2 hours of open time.

The mortar is applied either manually or by mechanical means at a nominal thickness of 15 to 20 mm. A drying period of 3 to 4 days must be respected. If a finishing layer is applied to the Unilit 30 after 1 week a bonding layer of Unilit 15/P1 or Unilit 15/P2 is required.

The mortars must not be applied at temperatures below +5°C nor when a risk of frost exists. They should never be applied on to a frozen surface or in the case of thick fog. In hot, windy and dry conditions measures should be taken to prevent accelerated drying out of the freshly applied mortars. Applied mortars must be protected from frost and direct sunlight for 48 to 72 hours after their application.

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