How often should you run the test?

Once a year is enough, ideally in spring when you inspect the rest of the envelope. It takes a minute and a glass of water.

Can I re-treat over it?

Yes, on a clean, dry surface. A penetrating repellent forms no film, so there is nothing to strip before putting product back on.

Does the beading effect disappear all at once?

No, it fades gradually and unevenly. The most exposed areas lose it first, which is exactly why comparing two areas is worth doing.

How to tell if your water repellent still works

Short answer

Pour a little water on the surface. If it beads up and rolls off, the treatment is still working. If it spreads and darkens the material, it has lost its effect. It is the simplest test there is, and it is exactly the principle a lab measures as contact angle.

How do you run the water drop test?

Pick a representative area, clean and dry, and pour a little water on it. Watch the shape the drop takes. A domed drop that rolls means a surface shedding water. A drop that flattens and darkens the material means water is going in.

This is not a subjective impression. Wetting physics classifies surfaces by contact angle: past 90 degrees a surface is hydrophobic, past 150 degrees superhydrophobic. The standardized measurement is made under ASTM D7334. What you see by eye is the coarse version of that measurement.

Where should you look first?

At the most exposed areas, because they lose the effect first. South-facing slopes for radiation, low slopes and areas that stay wet a long time for water.

Compare against a sheltered area of the same material. A clear gap between the two means exposure is doing the work, and that is the most useful reading you can get without an instrument.

How long should it last?

Our product specification states protection of up to 15 years. That is a manufacturer specification and not the result of an independent test, and we say so plainly.

Field literature on this product class is encouraging without being a promise: Christodoulou and co-authors (2013) found that silane impregnation retained a residual protective effect roughly 20 years after application on reinforced concrete. Durability for the class is tested under ASTM G154.

What if the effect is gone?

A surface with no beading left gets re-treated, after cleaning and full drying, the same as a first application. There is nothing to strip: a penetrating product leaves no film to remove.

If you have a warranty it came from our crews and it covers product performance, meaning water repellency and UV resistance. It runs 15 years if the roof was under 10 years old at application and 10 years if it was older, and it does not cover labour. An application you did yourself opens no warranty.

Frequently asked questions

How often should you run the test?: Once a year is enough, ideally in spring when you inspect the rest of the envelope. It takes a minute and a glass of water.
Can I re-treat over it?: Yes, on a clean, dry surface. A penetrating repellent forms no film, so there is nothing to strip before putting product back on.
Does the beading effect disappear all at once?: No, it fades gradually and unevenly. The most exposed areas lose it first, which is exactly why comparing two areas is worth doing.

Sources

These are the published sources behind the claims above. They describe the product CLASS (silane and siloxane repellents), not tests on Nanoxeal itself. We keep that distinction.

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