Frequently Asked Questions

How many coats of Nitoproof 600 are required and what is the minimum curing time between coats?

A minimum of two coats of Nitoproof 600 are required to achieve the specified waterproof membrane performance, with three coats recommended for water-retaining applications (tanks, swimming pools, basements under high hydrostatic head) where the highest reliability is needed. The first coat is applied to the primed and prepared substrate by stiff brush or roller at a coverage of approximately 1.0 to 1.5 kg per square metre (mixed material). The second coat is applied at right angles to the first (cross-coating) at the same coverage rate after the first coat has dried to a firm, touch-dry state — typically 3 to 6 hours at 25 to 30 degrees Celsius. The third coat (where specified) is applied after the second coat has similarly dried to touch-dry. In hot summer conditions, drying between coats is faster — as little as 2 to 3 hours. In humid or cool conditions, allow up to 8 to 12 hours between coats. The minimum total cure before water exposure is 7 days for water-retaining applications, with 28 days recommended before filling a water tank or swimming pool.

Can Nitoproof 600 be applied to a concrete surface that is damp from recent rain?

Nitoproof 600 has an advantage over many other waterproofing products in that it can be applied to a damp (surface wet) concrete substrate — the cementitious component of the coating is compatible with moist concrete and does not require a bone-dry substrate for adhesion and curing. However, there is a difference between a damp substrate (saturated surface-dry — pores are saturated but no free surface water visible) and a wet substrate (free water pooled or running on the surface). Nitoproof 600 should be applied to a damp or saturated surface-dry substrate — any free standing water or pools must be removed before application. Applying Nitoproof 600 to a pooled wet surface dilutes the coating at the application interface and reduces the adhesion and waterproofing performance of the first coat. In monsoon conditions where the substrate is continuously being wetted by rain, temporary protection (tarpaulin) to stop direct rain on the surface to be coated is needed before application, while allowing the underlying substrate to remain at the damp condition typical of monsoon humidity.

What is the difference between Nitoproof 600 and Brushbond RF for flat roof waterproofing?

Both Nitoproof 600 and Brushbond RF are polymer-modified cementitious waterproof coatings from Fosroc suitable for flat roof waterproofing, and they have similar application methods (brush or roller in multiple coats). The main differences are in the formulation approach and the performance characteristics that make each more appropriate for specific applications. Brushbond RF is a single-component product (dry powder only, just add water) with reinforcing fibres that provide improved crack bridging in the cured coating — it is well-suited for rooftops where minor cracking of the substrate is expected and where the single-component convenience is valued. Nitoproof 600 is a two-component product with a separate liquid polymer that allows a higher and more consistent polymer content in the cured coating — the higher polymer level provides better flexibility and adhesion, making it the preferred choice for water-retaining applications (tanks, pools) and for basement walls where the coating must resist higher hydrostatic pressure. For standard flat roof waterproofing, both products are appropriate — Brushbond RF for its convenience and Nitoproof 600 where higher flexibility and polymer content are specified.