Roof coatings are exposed to nature’s forces on a daily basis

One classifies weathering influence into:
Physical factors:
such as insulation (heat), cold (frost), rain and dew, wind and dust
Chemical factors:
such as air pollution, smoke, exhaust gases (acids and salts), as well as organic materials and ozone
Biological factors:
such as plants (mosses, fungi, lichens), animals (insects) and micro-organisms (bacteria, viruses)
To give a roof lasting protection, it needs the right roof coating material. The most important properties of a good roof coating are:

1: Lasting flexibility / Elongation at tear / Tensile strength

These properties are very important so that the material can expand in heat and cold. All Iso Paint roof coatings are based on 100% pure acrylate. This binder has lasting flexibility.

In Europe it is unfortunate that 70% of the roof coatings are made of “Styrene Acrylate.” Styrene acrylate contains the softener thalate. Thalates can not only be carcinogenic but are also leached out after 3-4 years. The styrene acrylate then turns hard and inflexible. That is why styrene acrylates are totally unsuitable for roof coatings. One should only use these for façade or internal coats of paint as they are not subject to high loads there.

The ISONIT roof coating with its elongation at tear of 197% was rated as HIGHLY ELASTIC.

2: Water permeability / Water absorption

The material for roof coatings should be water repellent so that water can run off and does not soak into the coating material. Because: if a roof coating absorbs too much water, you will have the ideal basis for algae and fungi. These then damage the stability of the roof foundation and at the same time accelerate the weathering process.

If 100 grams “ISONIT Roof Coating” is placed in a water basin for 24 hours, the paint absorbs 5 grams of water = 5% water absorption!

If 100 grams “Normal Roof Coating” is placed in a water basin for 24 hours, the paint absorbs 25 grams of water = 25% water absorption!

3: Adhesive strength

The material for roof coatings should be able to adhere to many types of bases, because good and long-lasting adherence means long durability.

4: UV and weather resistance

The material for roof coatings should be UV and weather resistant so that the roof looks good and receives long-term protection against weathering influences.

Outdoor weathering tests with ISONIT roof coatings show: Even after 2 years in Magdeburg’s industrial climate, there are no changes to the durability and only low to negligible changes are visible in the decorative properties.

5: Water vapour permeability / Breathing activity

The material for roof coatings should be capable of transporting moisture from the inside to the outside. If this is not the case, it may result in infections with fungi and/or moulds which is very damaging for the roof construction.

The ISONIT roof coating is highly pigmented with iron oxide colour pigments. These ensure a superior covering power so that 20% less paint is required on average than with “Normal Roof Coatings.” On average 0.4 – 0.5 ml/m2 is used with concrete shingles and 0.3 – 0.4 ml/ m2 with fibre cement.

To achieve adequate covering power, you need to use 0.8 – 0.9 ml/ m2 paint with a “Normal Roof Coating.” This of course has an influence on the breathing ability of the roof.

Why does the ISONIT Roof Coating have such good properties?

Iso Paint uses a specially developed binder comprised of 3 molecule sizes, which ensures superior properties. Below, you can see the illustration of a roofing tile surface with a “Normal Roof Coating” and a graphic of the ISONIT Roof Coating with its 3 molecule sizes: