Serious About Sealing.
INNERSEAL
Stop Damp in Concrete and Masonry
Have you noticed damp or mould in your basement? Want to seal your foundation from the inside? Or protect your newly built patio from moisture damage?
With Innerseal, it’s easy to stop damp in concrete and masonry — from the inside out. Innerseal is a deep-penetrating silicate-based sealer with outstanding test results and proven references from both the UK and abroad. It absorbs deep into the concrete, sealing the structure from within. Because it’s completely clear and colourless, you can apply it to any cement-based surface without altering the appearance. It’s easy to use, odour-free, and safe for both you and the environment.
Say goodbye to moisture problems, rust, mould, moss, and algae. Protect your property, save money, and reduce environmental impact — all in one step.
Perfect For:
Basements · Foundations · Patios · Chimneys · Walls · Floors · Ceilings
Any indoor or outdoor cement-based surface
Price per m²/ft²
max £5.93 / £0.55
Proven Worldwide,
Trusted at Home
With over 25 years of experience, Innerseal has been used in everything from homes and garages to large-scale infrastructure. Our deep-penetrating sealers have helped solve moisture problems in tunnels in Morocco, biogas tanks in Germany, and even nuclear plants in Sweden — but the same technology is protecting basements, driveways, and concrete floors across the UK today.
Independently
Certified Protection
All Innerseal products are fully certified and comply with international construction standards. In Europe, concrete protection systems must meet strict performance requirements — and our products go beyond them.
Our production is certified under NS-EN 1504-2 (System 2+), the European standard for long-term concrete protection — meaning what we claim is backed by testing, traceability, and third-party quality control.
Tested by
FAQ
ask us
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What is Innerseal and how does it work?
Innerseal is a deep-penetrating concrete and masonry sealer made in Norway. It works by using silicates that soak into the surface and chemically react within the material, sealing pores and microcracks from the inside. This blocks moisture, helping to prevent damp, mould, and damage, prolonging the lifespan of concrete.
What surfaces can I use Innerseal on?
Innerseal can be used on any cement-based surface — including concrete, mortar, render, screed, and fibre cement. Typical areas include foundations, basements, patios, garage floors, chimney stacks, walls, and ceilings.
Is Innerseal suitable for both indoor and outdoor use?
Yes. It’s completely safe and effective for both indoor and outdoor use. It’s colourless, odourless, and free from harmful fumes, making it ideal for living spaces as well as outdoor applications.
Can I use Innerseal on painted or sealed surfaces?
No — Innerseal must be applied directly to bare, absorbent concrete or masonry. If the surface has been painted or sealed, it should be cleaned or stripped first to allow proper penetration.
How long does Innerseal last once applied?
Innerseal offers long-term protection — often matching the lifespan of the structure itself. One application lasts for decades under normal conditions, especially when applied correctly on clean, unsealed surfaces.
How do I apply Innerseal?
Application on walls:
We recommend using a low-pressure sprayer (pump can). A wide brush or sponge can be used in tight areas. Thoroughly saturate the surface with Innerseal®. Repeat the process once the surface appears dry to the touch, ideally within 12 hours. On highly absorbent surfaces, a third coat may be necessary.
Application on horizontal surfaces (floors):
Pour Innerseal® directly onto the floor and spread using a soft brush or mop. Continue spreading the liquid as it is absorbed into the concrete. Keep the surface wet for 1 hour, then remove any excess Innerseal® with a rubber squeegee and rinse off with water.
Do I need any special tools to apply Innerseal?
No special tools are needed. A garden sprayer is ideal for most jobs. For small or tight areas, a roller or brush can be used. Just make sure the surface is clean and absorbent before applying.
Can I apply it myself or should I hire a professional?
YES – Innerseal is designed for both DIY and professional use. As long as you follow the instructions, most homeowners can apply it themselves. For larger commercial or structural jobs, you may wish to consult a professional for tips and advice.
How many coats/treatments do I need?
Most surfaces require two coats, applied wet-on-dry. On highly absorbent surfaces (like porous or weathered concrete), a third coat may be recommended for full protection.
If applying to a horizontal surface one fully saturated coat is enough.
How long does it take to dry?
Innerseal begins drying immediately after application. The surface is usually dry to the touch within 1–2 hours, but curing continues internally for up to 14 days. Avoid washing or heavy use during this curing period for best results.