A concrete worktop is essentially a small precast concrete element made to a kitchen tolerance, which is a much tighter standard than structural concrete work usually needs, combined with a sealing and maintenance regime that stone or laminate worktops don't require at all. A specification that just says 'concrete worktop, honed finish' leaves out the two things that decide whether it performs well in daily kitchen use.
Templating and cast tolerance
The spec should confirm the worktop is being cast from a physical or digital template of the actual cabinetry, taken after the units are installed and level, not from the kitchen drawing. It should also state the dimensional tolerance the caster works to and how any gaps at walls or upstands will be scribed and finished, since concrete worktops are cast off-site and delivered as a fixed, largely unadjustable piece.
Joint positions, where a worktop run is too large to cast in one piece, should be shown and agreed before casting, along with how the joint will be finished — a butt joint, a decorative reveal, or a seamless bonded joint.
Mix design and reinforcement
The concrete mix (often a fine-aggregate or GFRC — glass-fibre reinforced concrete — mix for thinner sections) and any internal reinforcement mesh should be specified, particularly for cantilevered sections such as a breakfast bar overhang, where the mix and reinforcement decide whether the worktop can span without cracking or sagging.
Integral features — a cast-in drainer, a sink cut-out, or a cast upstand — should be named individually since each affects the mould design and casting process.
Finish and pigmentation
The spec should state the surface finish (honed, polished, board-marked or textured) and any pigment or aggregate exposure being used, since these are chosen and mixed before casting and can't be changed afterwards. Colour consistency across a multi-piece run should be addressed by casting from the same batch where the worktop is delivered in sections.
Sealing schedule and maintenance
Concrete worktops need a penetrating sealer to resist staining, and the spec should state the sealer product, the number of coats, and the recommended re-sealing interval for kitchen use — without this, the worktop is vulnerable to staining from oil, wine and acidic foods from day one. Heat resistance and the advice given on trivets or heat pads should also be confirmed, since direct high heat can cause localised discolouration even on sealed concrete.
What a basic concrete worktop quote tends to leave out
Post-installation curing time before the worktop can be used, the sealing product and schedule, and delivery and installation method (including how a heavy single-piece top is manoeuvred into a finished kitchen) are commonly missing from an initial price.
- Template taken from installed cabinetry, not the drawing
- Mix design and reinforcement stated for any cantilevered section
- Sealer product, coat count and re-sealing interval
- Joint position and finish for multi-piece runs
- Delivery and installation method for the finished piece
Common questions
Can a concrete worktop be trimmed to fit on installation day?+
Only marginally — concrete worktops are cast close to final size from a template and are not designed to be cut down like a laminate or solid-surface top, which is why accurate templating before casting matters so much.
Do concrete worktops need to be resealed regularly?+
Yes, generally on a periodic schedule depending on the sealer used and how the surface is used — this should be stated at the point of purchase so you know what maintenance is expected, not discovered after staining occurs.
Is a concrete worktop strong enough to overhang as a breakfast bar with no legs?+
It can be, but only with a mix and reinforcement design (often GFRC with internal mesh) calculated for the specific span and thickness — this needs to be part of the specification before casting, not assumed to be fine at any span.
Get a concrete worktop specification with mix and sealing confirmed
We template from your installed cabinetry and specify mix, reinforcement and sealing before casting.