Lime Basecoat NHL 5 (EWI-748) – 21kg

EWI-748 Lime Basecoat is a premixed, powdered bonding mortar based on natural hydraulic lime (NHL5) as a binder, fine natural pozzolans, and selected additives that give it a longer working time in the application and great adherence to the substrate. Ideal for reinforcement, and regularisation and is especially recommended for the adhesion of insulation boards of EWI systems.

The unique properties of natural hydraulic lime in combination with natural pozzolan give the mortar optimal durability and high chemical resistance to acid rain and salts.

Lime Basecoat has a micro-porous internal structure that facilitates the passage of moisture and transforms it into water vapour. Thanks to the high permeability of the mortar, the water vapour is quickly evaporated. This generates the breathability of the building: it ensures a lower conductivity of the wall (which allows for significant energy savings in heating and cooling compared to the use of conventional cement) and favours the creation of an indoor climate of well-being, which improves the quality of life.

Intended Uses

Lime Basecoat is designed for use in new construction, renovation and bioconstruction in interior and exterior masonry works such as:

• Adhesion and reinforcement mortar for insulating boards EWI systems.
• Protection and regularisation of walls: as a first base coat on porous, slightly porous supports or insulating boards and as a finishing coat if rustic or fine textures are required.
• Raising of masonry walls.
• Laying of natural stone or settling of tiles.

Substrate Preparation

The substrate must be firm, dry and clean. Free of badly adhering parts, previous applications of grouts, water repellents, mould release agents or waxes, oxide, oils, fats, dust, efflorescence, vegetation, micro-organisms (mould or verdigris), pollution residues, building material or any element that prevents the excellent adhesion of the product to the support.

It is essential to dampen, but not flood, the support beforehand with water without pressure to guarantee a good adhesion and correct curing: avoiding dehydration and consequent cracking.

Product Preparation

Mix with water only at a rate of 4.5-5 L/bag of product.

Pour the water into a bucket and add Lime Adhesive gradually. Mix to the desired homogeneous consistency and free of lumps for 3 to 5 minutes. If more water is added than necessary, the mortar will lose mechanical strength and may crack.

Application

It is recommended to spread the mortar to a thickness of 4 to 10 mm, for thicknesses greater than 10 mm apply in two or more coats, preferably before the previous one has hardened.

Adhesion of insulation boards:

Apply a perimeter cordon 6 to 10cm wide and 2.5 to 5 cm thick on the plate, fill the inside of the cordon with 2 or more 8 to 10cm sticks, depending on the size of the plate. The mortar must cover at least 40% of the panel surface.

On supports with very good planimetry, it is possible to apply the mortar on the support and the insulating panels (double glueing), using a 10mm x 10mm notched trowel.

Regularisation on the insulating panels with mesh

Regularise at least 24 hours after adhesion of the plates.

1. Combed coat with a 6-8 mm notched trowel.
2. Laying of the mesh on top of the combed layer.
3. Fill in the mesh until the “groove and valley” are evened out. Do not flatten.
4. Apply a final coat of regularising mortar.

The mesh must comply with the following characteristics: 100% fibreglass, minimum mesh opening 5x4mm, weight 160 gr/m², chemical resistance to alkalis.
Failure to comply with the application instructions may adversely affect the finish and durability of the final result.

Storage Conditions

This product comes in powder form in a 21kg paper bag.

Store in a cool, dry place. Avoid ingress of water. Shelf life: up to 12 months from the date of manufacture.