Sikalastic®-612 is a one-component aromatic polyurethane liquid waterproofing membrane that cures with ambient moisture. Its great advantage on site is speed: it is rain resistant 10 minutes after application, which is decisive when working on a roof in unsettled weather.
It forms a continuous membrane with no joints or overlaps, elastic at low temperatures and permeable to water vapour, so the substrate can keep drying without causing blisters. It is the base of Sika's SikaRoof® MTC system.
✅ Main advantages
Rain resistant in 10 minutes: reduces the risk of having to redo work because of a shower.
One-component: ready to use, with no mixing and no A:B ratio to follow.
High strength: 4.5 N/mm² tensile strength without reinforcement and 8.0 N/mm² with reinforcement.
Vapour permeable: lets the substrate breathe and prevents blisters caused by trapped moisture.
Wide service range: from -20 °C to +80 °C.
With ETA: ETA-12/01278 (BBA) according to the ETAG 005 guideline and compliant with UNE-EN 14891.
🏗️ Recommended applications
Waterproofing of new and refurbished flat roofs.
Previously primed metal and fibre cement roofs.
Renovation over asphalt sheets and existing systems.
Details and critical points: parapets, drains, chimneys and junctions.
Roofs with complicated geometry where a sheet membrane would require many finishing details.
Waterproofing under tile in accordance with UNE-EN 14891.
📋 Technical specifications
Chemical base: one-component moisture-curing aromatic polyurethane
Colours: white (RAL 9010) · grey (RAL 7032) · terracotta · others on request
Density: approx. 1.42 kg/l (+23 °C)
Solids content: approx. 80% by weight · approx. 68% by volume
Check that the substrate is sound and clean and that its moisture content does not exceed 4% by weight.
Choose the primer: Sika® Concrete Primer or Sika® Bonding Primer on cementitious substrates, Sikalastic® Metal Primer N on metals, Sika® Reactivation Primer or Sikalastic®-810 on existing systems.
On wood, apply a full coat of Sikalastic® Carrier before the membrane.
Reinforce critical points with Sika® Reemat embedded in the membrane.
Apply the membrane by roller or brush, respecting the system consumption of 0.7-2.0 l/m².
Allow 6 hours before the next coat and avoid foot traffic until full cure (7 hours).
Always apply at an ambient temperature between +5 °C and +40 °C and with 5-85% relative humidity.
🛡️ Standards and certificates
ETA-12/01278 (BBA) according to the ETAG 005 guideline, with CE marking.
Compliant with UNE-EN 14891:2012-07 (liquid-applied waterproofing products under tile).
External fire performance BRoof (t1) according to ENV 1187.
Reaction to fire Euroclass E according to EN 13501-1.
📦 Supply formats
5 L metal container · approx. 7.1 kg · white, grey and terracotta
15 L metal container · approx. 21.3 kg · white, grey and terracotta
Units per box or pallet: not stated in the Product Data Sheet
💡 Professional tip: as it is a polyurethane that cures with moisture in the air, an open can is unforgiving. Once opened, use up the container within the working day: if you leave it half used, a hard skin forms on the surface and the rest gels. That is why, for detail work or finishing points, the 5 L container is the better choice even if it costs more per litre; the 15 L one is for large continuous areas. And don't confuse its maximum substrate moisture (4%) with that of an acrylic: here you have to measure it.
Technical data according to the Sikalastic®-612 Product Data Sheet from Sika España (version 07.01, March 2026).
Frequently asked questions
What is Sikalastic®-612 and what is it used for?
It is a one-component aromatic polyurethane liquid membrane that cures with ambient moisture. It waterproofs new and refurbished flat roofs, primed metal and fibre cement roofs, critical points and also under tile according to UNE-EN 14891.
How long does it take to become rain resistant?
It is rain resistant 10 minutes after application, at +20 °C and 50% relative humidity. It is touch-dry in 4 hours and full cure is reached in 7 hours.
Does it need a primer?
Yes, depending on the substrate. For example, Sika® Concrete Primer or Sika® Bonding Primer on cementitious substrates and Sikalastic® Metal Primer N on metals. On wood, a coat of Sikalastic® Carrier is applied first.
What is the consumption and what colours are available?
System consumption is 0.7 to 2.0 l/m². The colours are white, grey and terracotta, and others can be ordered. It is sold in 5 L and 15 L metal containers.
How should it be stored once opened?
As it cures with moisture in the air, the open container should be used up within the working day. Unopened, it keeps for 9 months between 0 °C and +25 °C.
Frequently asked questions about Sika products (mortars, adhesives and sealants)
How do I know which size and quantity to buy?
Each product page includes the approximate yield or consumption (for example kg/m² or metres of bead per cartridge) in the "Technical specifications" section. Calculate the surface area or thickness of your project and multiply by that consumption to find out how many units you need. If in doubt, contact us with the measurements of your job.
Where can I find the complete technical data sheet (Product Data Sheet)?
The description of each product already includes the main technical data (strengths, setting times, application temperature, applicable standards, etc.), taken from the official Sika Spain Product Data Sheet. If you need the complete PDF data sheet or the safety data sheet (SDS), write to us and we will send it to you.
Do these products comply with European regulations (CE marking)?
Most Sika products carry the CE marking in accordance with the relevant European standard (for example EN 1504 for structural repair, EN 12004 for tile adhesives, EN 13888 for grouts or EN 15651 for sealants). The exact standard for each reference is detailed in the "Standards and certificates" section of its product page.
What protective equipment do I need to apply them?
It depends on the product: cement-based mortars and adhesives are usually irritating to skin and eyes (gloves, goggles and a mask are recommended), while polyurethane sealants and adhesives require good ventilation. Always check the safety section of the product page and its safety data sheet (SDS) before use.
How should I store these products and how long do they last unopened?
Shelf life and storage conditions (temperature, humidity, protection from light) vary depending on the type of product (cementitious, polyurethane, epoxy, etc.) and are stated on the packaging and in the data sheet of each reference. In general, it is advisable to store in a dry place, protected from frost and direct sunlight.
Can I return a Sika product if I haven't used it?
Yes, you have 14 calendar days from receipt to exercise your right of withdrawal, provided the product is in its original packaging and has not been opened. The cost of return shipping is borne by the customer. Contact us at info@vetonek.com or via WhatsApp on +34 629 571 735.
How long does my order take to arrive?
We ship to mainland Spain, the Balearic Islands, Portugal and the other European countries we serve (France, Belgium, the Netherlands, Germany, Italy, etc.). The estimated delivery time is 3 to 9 working days (no shipping to the Canary Islands, Ceuta or Melilla).
Todo excelente. Tras una primera equivocación con el producto elegido, el equipo de atención al cliente se puedo a trabajar para solucionar el problema y darme una solución adecuada.
