UNILIT 10 (TD13 PA) BONDING BRIDGE LAYER
Outline specification : plastering, rendering, tadelakt
Unilit 10 is a traditional, dry premixed mineral bonding bridge layer based on natural hydraulic lime as the binder and appropriate well-graded aggregates.
Unilit 10 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 10 conforms to the European Standard UNI EN 998-1.
Area of Application
Unilit 10 is applied when the background is unsuitable to guarantee an optimum bonding of any base coat, either if the background shows little adherence (e.g. old powdering bricks or natural stones), or either if the background is characterised by a low water absorption, such as smooth concrete or granite surfaces. Unilit 10 can as well be applied as a bonding bridge on backgrounds which are saturated with water and/or soluble salts.
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 7 to 8 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 3 to 5 minutes.
A creamy workable mortar is obtained, which has approximately 2 hours of open time.
The mortar is applied manually or mechanically in an open structure, covering not more than 70% of the surface area. A drying time of at least 4 hours should be regarded.
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.