Weathercoat Seal is the layer behind the facade that most people never see. Short answer: it is Terraco’s one-component, fluid-applied acrylic water-resistive and air barrier. It goes on Terraco-approved exterior sheathing boards behind Terraco EIFS, and on concrete, block and other masonry behind metal panel cladding. It is applied by roller in two coats or by trowel in one, and it is not for areas of water immersion. This guide follows Terraco’s UAE technical data sheet.
Key facts
| Type | One-component fluid-applied water-resistive and air barrier |
| Binder | Acrylic |
| Colours | Blue, red |
| Application | Roller or brush (2 coats) or stainless-steel trowel (1 coat); no dilution |
| Wet film, roller | 1st coat 300 to 350 microns; 2nd coat 250 to 300 microns |
| Thickness, trowel | About 0.6 mm, one coat |
| Coverage | About 0.6 to 1.1 kg/m² |
| Application temperature | 5°C to 40°C |
| Packs | 25 kg pail |
Test data
| Property | Standard | Result |
|---|---|---|
| Surface burning characteristics | ASTM E84 | Class A |
| Water vapour transmission | ASTM E96/E96M-16 | Below 1.0 perms |
| Water resistance, 24 h immersion | ASTM D2247-15 | No effect |
| Adhesive strength | – | At least 2.0 N/mm² |
| VOC | – | Below 5 g/l |
Where it is used
- On Terraco-approved exterior gypsum and cement board sheathing behind Terraco EIFS. For choosing the EIFS itself, see EIFS Alpha vs Perma vs Polar.
- On precast concrete, concrete block and other masonry, including behind metal panel cladding.
- On low- and high-rise residential and commercial buildings.
It is not a waterproofing for tanks, pools or wet rooms; the data sheet excludes areas of water immersion. For those, see Terracrete vs Weathercoat GP.
How it is applied
- Prepare. Remove dust, dirt and foreign matter; the substrate must be free of salts, oil, grease and ridges.
- Treat the details first. Joints, board edges, corners and fastener locations get Weathercoat Seal with Terraco-approved sheathing tape embedded.
- Wait 4 to 6 hours, then coat the full surface: two roller coats at the wet film thicknesses above, or one trowel coat of about 0.6 mm.
- Let it dry fully, 3 to 4 days depending on climate, before the next system layer. Do not apply if rain is expected within 24 hours.
How much you need
At 0.6 to 1.1 kg/m², one 25 kg pail covers roughly 23 to 42 m². A 400 m² facade needs 240 to 440 kg, or 10 to 18 pails, plus extra for detail treatment at joints and openings. These are our own calculations from Terraco’s coverage figure.
Frequently asked questions
Is it the same as Weathercoat GP?
No. Weathercoat GP is a two-component cement-acrylic waterproofing for roofs, wet rooms and water-retaining structures. Weathercoat Seal is a one-component air and water-resistive barrier for walls behind EIFS or cladding. See our Weathercoat GP guide.
Can it be left exposed?
It is a barrier layer that sits behind the EIFS or cladding. The data sheet says to let it dry fully, 3 to 4 days, before the next system layer goes on.
Buying Weathercoat Seal in Sharjah and Dubai
Al Tashteb Al Saree is an authorised Terraco distributor and supplies Weathercoat Seal and Terraco EIFS components direct from the manufacturer. Message us on WhatsApp with the facade area. You can also browse every Terraco product we supply.
Sources
Retrieved 1 November 2026. Quantities are our own calculations. The main image is illustrative.
