Pure acrylic coatings offer the greatest resistance to ultra-violet light radiation from sunlight and are generally superior to the other single pack co-polymers such as styrene acrylics, polyvinyl acetates, and vinyl acrylics. Pigments used in these coatings should be manufactured from high quality light-fast oxides such as "BayFerrox" oxides.

Traditionally solvent based coatings were used to restore roofs, but today, modern water-based polymers are significantly superior and offer a number of advantages.

5.1 NUTECH ACRYLIC SEALERS AND PRIMERS

The condition of the tile or roof surface after cleaning will determine the most suitable sealer.
The following products are recommended:

NuPrime Thin, clear, penetrative primer for powdery oxidised surfaces.
Master Thick, clear, 100& acrylic sealer for bare cement tiles.
GP Primer Thick, light grey, acrylic adhesion promoted primer for porous tiles.

Asbestos Sealer Thick, clear, penetrative sealer for locking down asbestos sheeting.

Anti-Corrosive Metal Primer Thick, light grey, anti-corrosive acrylic adhesion primer for the protection and preparation of sheet metal. (Used in conjunction with Nutech Rust Converter)
All of these primers and sealers resist attack from moss, lichen, and bacterial growth.

Sealing and priming a roof should not be carried out when the surface temperature is outside the range of 10 to 30 Degrees Celsius. In very hot weather the surface may be cooled with water to assist penetration and adhesion.

5.2 SPECIALTY ROOF PRODUCTS

NuBond Thick, clear, 100% acrylic additive for increasing the density and flexibility of concrete
Emastak Thick, black, high-build bituminous sealer for waterproofing of potable water tanks.
Waterproof Membrane Very flexible low sheen waterproof acrylic membrane.

5.3 NUTECH ACRYLIC FINISH COATS

The following products provide excellent water and alkali resistance and guarantee excellent gloss retention, hardness, flexibility, adhesion, and weathering properties.

Colourfast Premium quality economical semi-gloss acrylic coating.
Nuflex Premium 100% acrylic semi-gloss coating.
Metalics Premium 100% acrylic high gloss coating with a metallic finish for added heat reflection.
Tileflex 2000 Premium 100% acrylic high gloss coating, enhanced with Surface Cleaning Nano Technology for superior protection, dirt resistance, gloss levels, and enhanced durability.

Because water-based acrylic coatings are water soluble you must ensure that weather conditions are favorable. Rain, moisture, or dew contacting the coating before drying is complete will cause damage and reduce gloss. In colder weather, it is advisable to complete spraying before early afternoon. As temperatures drop below 10 Degrees Celsius in late afternoon, the coating will not form a film and may be damaged by climatic effects.

Condensation can also form on roofs with surface temperatures even up to 22 Degrees Celsius subject to ambient air temperature and relative humidity. This can lead to damage if the coating is not cured properly.

Overcoating an uncured coat too early is a common cause of adhesion loss and coating failure. Independent curing of each coat is a critical requirement, particularly in cold weather.

Coating in very hot conditions can lead to very poor surface adhesion, lack of product build, and also greatly reduced surface gloss levels. In very hot weather the surface may be cooled with water to assist penetration and adhesion.

5.4 TERRACOTTA TILE COATINGS

Water-based acrylic coatings are not recommended for terracotta tiles, particularly glazed, semi-glazed, and highly vitrified tiles. The most advanced coating developed by NuTech for terracotta tiles is:

TerraGlaze Solvent based alkyd oil high gloss coating.
TerraGlaze is available as a clear high gloss glaze, or in six popular colours. TerraGlaze is a high solids coating containing premium quality ultra-violet light absorbers and stabilisers to improve durability and clarity of the coating.

WARNING: Terraglaze is NOT recommended for fully glazed or vitrified tiles.

5.5 OTHER PRODUCTS OF INTEREST

Silicon Sealer Clear, thin, penetrative solvent based waterproofing coating.
Pavecoat Clear or coloured solvent based sealer for concrete surfaces
(Used in conjunction with Nutech Anti-Slip Additive)
Accopol 847 Clear or coloured solvent based topcoat for new glossy tiles or metal sheeting.