A facade differs from a horizontal surface in one way that changes everything: masonry has to give up moisture. Water reaches a wall not only from rain but from inside the building, and it has to have a way out. A preparation that seals the wall tight will trap moisture inside the masonry - which is why vapour permeability is the first criterion on a facade.
In short
Vapour permeability is a condition, not an extra.
A sealed skin on a wall traps moisture in the masonry.
The substrate decides the product.
Brick, mineral render, stone and roof tile behave differently.
A roof is its own matter.
Clay and concrete roof tiles have products of their own.
Wash before, not after.
Remove algae and streaks before sealing, or the sealer will lock them in.
Four substrates, four conversations
Brick and engineering brick - an excellent choice is the siloxane-based CTS Chemistry VC-1, or the water- and oil-repellent Eksil EH-20, for walls that also need protecting from oil. Brick is absorbent and usually takes noticeably more product than concrete.
Stone on a wall - how the surface is worked matters as much as the type of stone. More in the natural stone guide. Roof tiles - VD-1 for clay and concrete tiles; it forms no coating and leaves the vapour permeability of the roof unchanged. Several substrates at once - a great solution is ImperGuard Ultra from Guard Industry: one product for facades, roofs and paving.
A facade against a horizontal surface
| Criterion | Facade | Drive, terrace |
|---|---|---|
| Vapour permeability | A necessary condition | Rarely decisive |
| Main adversary | Driving rain, algae, runs | Standing water, oil, frost |
| Visual finish | Usually invisible - a wall should look like a wall | Invisible or wet look, your choice |
| Access to the work | Scaffolding, working at height | From ground level |
Deepening colour on a facade
A wet look is sometimes wanted on a wall - particularly on facing stone and brick, where it brings out the pattern of the material. An excellent choice here is the silane-based Eksil EH-16 - it gently deepens the colour of the substrate while keeping the masonry vapour-permeable.
The effect cannot be undone, so on a wall facing the street, start with a test patch. More in the guide to the finish.
Facades and roofs
Professional products for brick, render, stone and roof tiles.
PremiumŚrodek do czyszczenia elewacji i fasad Guard Industry
329,00 zł
62,45 zł/L
StandardSandstone wall and facade sealer VP-1 CTS Chemistry
45,40 zł
36,18 zł/L
StandardClay and concrete roof tile sealer VD-1 CTS Chemistry
45,51 zł
39,36 zł/L
StandardBrick and engineering brick sealer VC-1 CTS Chemistry
42,50 zł
33,90 zł/L
StandardSplit-face concrete block sealer VBe-1 CTS Chemistry
42,71 zł
30,00 zł/L≈ 3,75 zł/m²
StandardConcrete wall sealer, wet look VB-2 CTS Chemistry
45,01 zł
35,90 zł/L
StandardConcrete wall sealer, invisible finish VB-1 CTS Chemistry
31,89 zł
25,80 zł/L
StandardSandstone sealer, invisible finish HP-1 CTS Chemistry
42,80 zł
33,94 zł/L
Roof and facade, step by step
Washing and sealing a roof and a wall each have their own guide. Start from the job in front of you.
- Roof: cleaning moss off roof tiles, sealing roof tiles.
- Facade: cleaning algae off a facade, where green growth comes from.
- Choosing and preparing: preparing the substrate, water-based or solvent-based sealer, invisible or colour-deepening sealer.
Common questions
Will a facade sealer trap moisture in the masonry?
Not if it is vapour-permeable - a sealer like that limits water getting in from outside while still letting the masonry give up moisture.
Can fresh render be sealed?
Not straight away - render, like concrete, has to cure first. You will find the required time in the technical data of the sealer you choose.
Do roof tiles have to be sealed?
There is no obligation. A roof tile sealer limits water uptake and makes the covering more resistant to soiling; whether it pays off depends on the state of the roof and how much it gets overgrown. On an old, cracked roof, chemistry is no substitute for replacement.
Will one preparation handle both a facade and a roof?
Yes. ImperGuard Ultra from Guard Industry is made for facades, roofs and paving alike. Before you buy, make sure its list of recommended substrates includes the material of your wall and roof.
