"Anti-damp paint" is a marketing label, not a technical category. On the same shelf you'll find three products that have nothing to do with each other and behave in opposite ways on a problem wall. Choosing wrong isn't just wasting €20: it can make worse what you wanted to fix. Here's what's behind the name and how to decide.
First things first: no paint gets rid of damp
Damp in a wall has a source: water vapour from the air that condenses, water rising from the ground or water getting in from outside. Paint doesn't remove that source. What it can do is change how the surface behaves: let vapour through or block it, encourage or discourage mould, hold up or lift off with salts. So the right question isn't "which anti-damp paint is best?" but "what kind of damp do I have, and which paint goes well with it?". If you don't know yet, start with how to tell what kind of damp you have in 5 minutes.
The three types sold as anti-damp
1. Waterproofing plastic paint
An acrylic or vinyl paint with lots of resin that forms a continuous, closed film. It's sold as "anti-damp" because liquid water doesn't get through it. The problem is that vapour doesn't either. On a wall with condensation, water settles on the film and can't evaporate into the wall or be absorbed: it stays on the surface, builds up, and mould grows on top just the same or worse. On salt-affected walls, the paint swells and falls off because salts crystallise behind it and push. It makes sense in very specific places (an outdoor plinth, for example), not inside a bedroom.
2. Paint with biocide
A normal plastic paint with an added fungicide. While the biocide is active, fungi don't grow. Manufacturers usually quote one to two years; with frequent cleaning or a lot of moisture, less. After that, the wall goes back to what it was: a cold plastic film that vapour condenses on. It delays the problem; it doesn't solve it, and it changes nothing about the cause.
3. Breathable, anti-condensation paint
What matters here is that the film doesn't seal the wall: it lets water vapour out of the wall instead of trapping it. MATE5000 and Pared Seca belong to this group: water-based paints with Quartzene® + Graphene/CaCO₃® Technology, based on mineral materials and aerogel, which according to their technical data sheets changes the thermal behaviour of the paint film and helps reduce the surface conditions that encourage condensation. They don't promise to kill mould: if the wall has had fungi, it's cleaned and prepared with Sellador Total L44, which regulates absorption and improves adhesion of the finish.
| Waterproof plastic | With biocide | Breathable and anti-condensation | |
|---|---|---|---|
| Lets vapour through | No | No | Yes |
| Condensation | Makes it worse | Delays mould | Helps reduce the conditions that encourage condensation |
| Salt bloom | Lifts off | Lifts off | Holds up with a primer first |
| Water ingress | Hides it for a while | Hides it for a while | Stop the water getting in first |
| Finish | Satin or matt | Matt | Deep matt (MATE5000) |
MATE5000 AntiHumedad
Breathable, anti-condensation interior paint with a deep matt finish.4 L and 15 L · 12 colours · 5–7 m²/L
What breathable paint doesn't do
It's worth being clear so you don't buy something expecting what it can't deliver:
- It doesn't dry out a wall with rising damp. If water is coming up from the ground, it will keep coming up. Breathable paint doesn't trap water the way plastic paint does, but without treating the salts it will end up affected.
- It doesn't seal a leak. If water gets in through a crack, a window joint or a terrace, the paint gets wet from behind. The water has to be stopped first.
- It doesn't replace ventilation. It helps reduce condensation on the wall, but if a room produces a lot of vapour and is never aired, the excess moisture ends up on windows, fabrics and in wardrobes.
How to choose for your type of damp
The rule is simple: paint always goes last, and what changes is what you put on before it.
Condensation
Mould in corners and on ceilings, drops on windows, worse in winter. Clean off the mould, let it dry, prepare with Sellador Total L44 if there were fungi (on well-bonded existing paint with no mould, no primer is needed) and apply MATE5000 or Pared Seca in two coats. What to expect from them is in anti-condensation paint: what it does and doesn't do; the full treatment, in condensation.
Salt bloom or rising damp
White powder, blistered paint low down, render that crumbles. Scrape dry, repair, apply NeutralySalt Primer to prevent salts crystallising on the surface (1 L covers around 25–30 m²) and, once dry, MATE5000. If the damp band rises every year or the wall is in contact with the ground, read when building work is needed.
Water ingress
A stain with a clear edge that grows when it rains. Find where the water gets in. On walls, repair cracks and joints from outside; on flat roofs and roofs, Cool Roof Therm. Once the wall is dry, Sellador Total L44 as a primer (9–10 m²/L) and MATE5000 indoors. If the water ingress is structural (a growing crack, a broken downpipe, worn-out roof waterproofing), you need a professional before painting anything. We explain it in water ingress.
Price, coverage and what it really costs
With coverage of 5–7 m²/L per coat, a 4 L tin of MATE5000 covers around 10–14 m² in two coats and costs €19.02; the 15 L tin covers around 37–52 m² and costs €65.79. For a 12 m² bedroom with 2.5 m walls, deducting door and window and including the ceiling, you're looking at a 15 L tin. You can fine-tune the quantity with the calculator. On-screen colours may vary from the real thing.
When it isn't a paint question
There are situations where no paint, breathable or not, is the answer: severe thermal bridges that condense every day, buried walls without drainage, roofs with worn-out bitumen membrane or crumbling plasterboard. In those cases paint is the last step of a building job, not a substitute for it. If you don't know which case you're in, send photos and we'll tell you, no strings attached. And if you manage several homes or a building, write to us and we'll look at it with you.
Guía escrita y revisada por el Equipo Humix Paint con los datos de las fichas técnicas de cada producto. La pintura actúa en la superficie: si el agua sube del suelo o entra de fuera, primero se trata la causa.
