Are Microcement Worktops Waterproof?
Yes — microcement is waterproof when applied correctly as part of a complete system. In kitchens and bathrooms, the microcement layers provide water resistance, and the sealer is primarily there to improve stain resistance and make the surface easier to live with day to day.
Waterproof vs stain resistant: what’s the difference?
This is where people get muddled.
- Waterproofing is about stopping water passing through the surface system.
- Stain resistance is about stopping oils, wine, coffee, turmeric, and general kitchen mess from leaving marks.
Microcement can be waterproof as a system, but the sealer is what gives you the practical, wipe-clean stain resistance that matters on a worktop.
Why “belt and braces” matters in wet areas
In wet zones (showers, wet rooms, and areas around sinks) we take a belt and braces approach and recommend applying a tanking liquid to the substrate first.
Even if the microcement finish is waterproof, problems can occur if water finds a way behind the microcement — for example if a joint opens slightly due to substrate movement or thermal expansion. If moisture gets behind the system, it can cause:
- Loss of adhesion (debonding)
- Blistering or hollow-sounding areas
- Localised failure around joints, edges, or cut-outs
Tanking the substrate reduces the risk of water ingress behind the microcement and improves long-term reliability in high-exposure areas.
What about around sinks and taps?
Sink cut-outs, tap penetrations, and wet edges are the most demanding areas on a worktop. We recommend:
- Stable substrate and correct joint detailing
- Careful sealing around cut-outs and penetrations
- Using appropriate silicone detailing where needed
- Periodic checks in high-use wet zones
How do I know if protection is wearing?
Waterproofing and stain resistance don’t usually “fail overnight”. If the surface starts to look dull in heavy-use zones, or marks are easier to pick up than before, it may be time to refresh the protective layers.
Microcement waterproofing FAQs
Is microcement waterproof?
Yes, microcement can be waterproof when applied correctly as part of a complete system, using the right primers, coats, and detailing.
What does the sealer do on a microcement worktop?
The sealer primarily improves stain resistance and makes the surface more practical for kitchen use by reducing absorption and making it easier to wipe clean.
Why use tanking liquid under microcement in wet areas?
In wet zones, tanking the substrate helps prevent moisture ingress behind the microcement. If water gets behind the system (for example through an opened joint caused by movement or thermal expansion), it can lead to debonding or localised failure.
Can microcement be used around sinks?
Yes, but it needs careful detailing around cut-outs and penetrations, and we recommend a belt and braces approach in high-exposure areas.
