Polished Concrete Overlay Systems

What Is a Polished Concrete Overlay?

A polished concrete overlay is a specialist cementitious topping, bonded onto an existing concrete slab and then ground, honed and polished in the same way as a direct polish would be. We install TRU, a system made by CTS Rapid Set, when the existing concrete isn’t a good candidate for polishing on its own, whether that’s due to damage, contamination, uneven aggregate, or a slab that’s simply too inconsistent to give the finish you want.

Unlike direct polishing, where the finish depends on the existing slab, an overlay creates a new polishable surface. This gives you greater control over colour, aggregate exposure and the finished appearance.

Overlay or Direct Polishing? An Honest Answer

Where the existing slab is in good condition, direct polishing often needs less material and fewer installation stages, so it can work out more cost-effective. You can read about that process on our Polished Concrete Floors page, and we’ll always tell you honestly which route suits your floor.

An overlay makes sense when the existing concrete can’t give you the finish you want: it’s damaged, heavily patched, contaminated, or too inconsistent for a direct polish to look right. It’s also worth knowing upfront that a TRU overlay is still a genuine cement-based floor, not a synthetic or artificial finish. It will still show natural variation, movement and character. That is part of what gives it the appearance of genuine polished concrete rather than a manufactured imitation. If you want perfectly even colour and aggregate with zero variation, an overlay is not the right fit either. Vinyl or tiles may suit that expectation better.

The Installation Process

Every project starts with a proper assessment of the existing slab and a discussion of the finish you’re after. From there, the process follows several stages: detailed substrate preparation, correct priming, and proper treatment of any existing joints or movement cracks, since these can reflect through the new surface if they aren’t addressed first. Once that groundwork is right, we mix and place the TRU overlay to the correct thickness, then grind, grout, densify, seal and polish the surface once it’s cured.

Correct preparation, timing and product consistency all matter here. We’ll talk you through exactly what your project involves once we’ve seen the space.

Where an Overlay Genuinely Helps

An overlay suits refurbishments, design-led projects, retail spaces and commercial areas, as well as homes, where the existing concrete isn’t suitable for direct polishing. It’s a good option for damaged, heavily patched, contaminated or visually inconsistent slabs, including floors that need a new level and polishable wearing surface, where the existing concrete wouldn’t give you the finish you’re after otherwise.

Where an Overlay Isn’t the Right Fix

An overlay is only as good as the substrate underneath it, so it isn’t a way to disguise serious problems. It shouldn’t be used to hide structural issues, active cracking, movement or damp, and it isn’t a substitute for correct floor design or movement joints. Moisture and contamination need assessing properly before installation, and the substrate has to be sound, clean and correctly prepared first. Done properly, TRU delivers a genuinely high-performance floor. Done as a shortcut over an unresolved problem, it won’t hold up, and we’ll always tell you honestly if that’s what we’re looking at.

TRU overlays can suit both residential polished concrete floors and commercial polished concrete floors where direct polishing cannot achieve the required result.

Trained and Certified TRU Installers

We’ve completed the Smart Floor TRU Training Academy, covering correct assessment, substrate preparation, mixing, placing and the full grind, densify, seal and polish process for CTS Rapid Set’s TRU systems. This training supports a correctly specified installation from initial assessment and preparation through to the final polished finish.