Outline specification : flooring, roofing, tadelakt


Unilit 65 is a traditional, dry premixed mineral base and stone repair mortar based on natural hydraulic lime as the binder and appropriate well-graded aggregates.

Unilit 65 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.

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 65 conforms to the European Standard UNI EN 998-1.

Application Area 

Unilit 65 is especially suited for all kinds of applications applying traditional building materials both in new construction, renovation as well as restauration. Amongst others, Unilit 65 can therefore be applied onto a variety of substrates (e.g. traditional brickwork and natural stone masonry, pre-existing renders and plasters, etc.) as an undercoat or finishing layer for both plastering and rendering, as a bedding and pointing mortar in the case of traditional masonry constructions, as a bedding mortar for the gluing of terracotta tiles and stone slabs or for stone restoration purposes.

Thanks to its natural pore structure and low content of soluble salts, Unilit 65 regulates the moisture content within the masonry, eliminating practically all known problems related to frost, salt damage and lime bloom, providing that excessive damp and/or salt problems are not prevelant, and that the substrate is stable.


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 (4 to 5 l  in case of 25 kg). Mixing is undertaken with a slow speed electric paddle for a period of 3 to 4 minutes.

A creamy workable mortar is obtained, which has approximately 3 hours of open time.

Depending on the application the mortar is applied either manually or by mechanical means at the required thickness. Stone repairs and/or undercoats at a nominal layer thickness and/or (re)pointing at a nominal joint width of 10 to 20 mm, respectively, require the application of the coarser Unilit 65N. The somewhat finer granulated Unilit 65M is applied at a nominal thickness of 5 to 8 mm, while even thinner applications require the application of Unilit 65F. Layers exceeding 20 mm in thickness are applied in subsequent passes, each at a maximum layer thickness as specified above. If desired, a coloured finish can be applied afterward with a mineral paint, either a lime wash or either a silicate paint. A drying period of at least 1 week must be respected.

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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