Ronacrete Ronafix For Renders

Ronacrete Ronafix For Renders is suitable for use within tanking renders and weatherproofing renders in a mix design.

Best Uses

Ronafix is a single part modified styrene butadiene liquid additive for cement mortars which enhances physical and chemical properties, allows mortars to be placed in thin section, provides waterproofing and resistance to frost and promotes adhesion to building surfaces.

Mortars containing Ronafix are used for a wide range of applications where thin high strength high performance mortars are required. Typical minimum application depth is 10mm.

There are 2 mix designs when using Ronafix as a waterproof render. Ronafix Mix Design A is used for weatherproofing and Ronafix Mix Design E is used for tanking.

• Waterproof (Mix Design E)
• Weatherproof (Mix Design A)
• Frost-proof
• High compressive strength
• High tensile strength
• High flexural strength

Mix Design A

• Cement: 50 Kg (By weight)
• Medium Sharp Sand: 125 Kg (By weight)
• Ronafix: 9 Litres
• Water: 9 litres (approximately)

See the data sheet for the full mix requirements.

Mix Design E

• Cement: 50 Kg (By weight)
• Medium Sharp Sand: 125 Kg (By weight)
• Ronafix: 14 Litres
• Water: 4 litres (approximately)

See the data sheet for the full mix requirements.

Application

Preparation

The substrate on which the Ronafix render is being placed must be structurally sound and stable and suitable to receive and support a strong render. Surfaces should ideally be prepared by recyclical shot blasting, water/grit blasting or similar means to expose the aggregate and provide a mechanical key. All grease, oil, dirt and deleterious material must be removed by vacuuming.

Damping
The prepared surface must be thoroughly dampened with clean water. All surplus and standing water must be removed before the primer is applied.

Priming
Brush apply a primer of 1:1 Ronafix : cement to the damp surface immediately before applying the Ronafix modified mortar. Mix the primer thoroughly and apply evenly over the surface ensuring total and uniform coverage. Only prime an area which can be covered by the render within the working time of the primer.

Note that the primer must not be allowed to dry. If it dries it must be thoroughly cross hatched scratched and reapplied.

Mixing

Mix the Ronafix modified mortar and apply in layers to achieve the required thickness, reform the original profile of the concrete and cover reinforcing steel.

Layer thickness will vary according to the nature of the substrate, the shape and size of area being repaired and mixing and application technique. Ronafix modified mortars can be mixed by hand or machine. Machine mixing will more easily provide a mortar with even dispersion of mix components and a lower water/cement ratio. The use of a forced action mixer (eg. Creteangle or drill and paddle) will provide optimum performance; free fall mixers cause the mortar to
ball up with a resultant reduction in performance and must not be used.

Placing

As soon as the material is mixed render it onto the wet/tacky primer, using conventional plastering techniques ensuring total contact with the substrate and ensuring the render does not slump or slide away from the surface.

If applying two or more coats of Ronafix render apply each layer after the previous layer has firmed up sufficiently to support its weight without slumping or pulling away. Keying and priming between layers is necessary to ensure total adhesion through the render.

When applying waterproof renders using mix design E it is necessary to apply not less than two coats, each not less than 10mm thick. Joints must be staggered and the render should be carried down on to the floor to form a coving. The joint between a waterproof render and a waterproof screed must also be staggered.

Curing
As soon as possible after finishing the surface cure the surface with Ronacrete Monocure 50. Alternatively use tight fitting polythene to prevent rapid moisture loss and surface cracking and crazing.