Everything you need to cast, process, and seal a polished concrete worktop up to up to 2 sqm — in one complete kit. No prior experience required. Just add water.

Best for: Standard kitchen worktop, dining table, bar top, large desk, bathroom double vanity

Why Buy the Kit?

Making a concrete worktop involves several products that all need to work together — the concrete mix, mould release, surface processing products, reinforcement, and sealer. Buy them separately and you risk ordering the wrong quantities or missing something critical.

This kit bundles everything into one order at the right quantities for your project size. No guesswork. No missing products. No maths.

What’s In the Kit

4 bags GFRC Concrete Worktop Mix (2.4 sqm)
1 bottle Water-Based Mould Release Agent (20 sqm)
1 Pack Concrete Lab Sealer (Matt or Satin; 10sqm)
4 x Fibreglass Reinforcement Bars (1 cutout e.g. sink or hob opening)
1 GFRC Processing Kit (smoothing paste, etch & clean, neutraliser; 3 sqm)


Get a Premium 40mm Edge — Without the Weight

Want a thick, substantial-looking worktop edge? Our recommended technique uses a 20mm core with a shuttered 40mm lip along the visible front edge. You get the premium look of a chunky concrete worktop at a fraction of the weight and material cost.

Because precast concrete is cast upside down in a mould, the lip is formed at the bottom and becomes the visible edge once flipped. Our tutorial video walks you through exactly how to set this up.

How It Works — 5 Simple Steps

1. Build Your Mould — Use melamine board or similar smooth sheet material. Apply the included Mould Release Agent so your concrete releases cleanly. Our casting guide PDF shows you exactly how, including how to form the 40mm lip.

2. Mix & Pour — Just add water & additives. Our GFRC mix is self-compacting — it flows into every corner of your mould like liquid stone. No vibration needed.

3. Cure & Demould — Allow 18 hours before demoulding. Your concrete reaches twice the strength of standard concrete within 7 days.

4. Process the Surface — Use the included Processing Kit to fill any pinholes with colour-matched smoothing paste, then etch and neutralise the surface ready for sealing.

5. Seal & Protect — Apply the included Concrete Lab Sealer for a stain-resistant, water-resistant finish. Choose Matt for a natural concrete look or Satin for a soft sheen.

Available Colours

Off White · Light Grey · Mid Grey · Dark Grey · Pink

Not sure which colour? Order our Cast Concrete Colour Sample Pack (£8) to see the real colour, texture, and finish before you commit.

Video Tutorials & Guides Included

Every kit comes with access to our complete library of step-by-step video tutorials and downloadable PDF guides covering mixing, moulding, casting, processing, and sealing. Watch the full process before you start — no surprises.

Good to Know

This kit includes 4 reinforcement bars — enough for one cutout (sink or hob). If your worktop has a sink and a hob cutout, add an extra Fibreglass Reinforcement Bar 4-Pack (£20) to your order.

The mould is typically made from melamine-faced board, available from any timber merchant or DIY store. Mould materials are not included in the kit.

For extra protection and a beautiful satin sheen, add Concrete Wax (£16) to your order. Food-safe, easy to apply, and recommended for all worktop projects.

Frequently Asked Questions

Is this really DIY-friendly?
Yes. Our kits are designed for people with no concrete experience. The mix is pre-weighed and pre-blended — you literally just add water. Combined with our step-by-step video tutorials, first-timers consistently achieve professional results.

How thick should I cast?
We recommend a 20mm core for internal worktops. If you want a thicker-looking edge (most people do), use our shuttered lip technique to create a 40mm visible edge while keeping the main surface at 20mm. This saves material, reduces weight, and looks fantastic.

What tools do I need?
A mixing paddle and drill, a roller and frame for the sealer, and an orbital sander for finishing. No heavy machinery or specialist equipment required.

What about the mould?
The mould is typically made from melamine-faced board, available from any timber merchant or DIY store. Our casting guide PDF gives you full mould-building instructions including measurements and tips.

How long does the whole process take?
Most people complete their worktop over a weekend. Mould building takes a few hours. Mixing and pouring is under an hour. You wait 18 hours to demould, then processing and sealing can be done over the following days.

Can I use this outdoors?
Yes — our GFRC mix is suitable for indoor and outdoor use. For outdoor projects, we recommend a minimum 30mm core thickness and annual resealing for longevity.

Can I see the colours before ordering?
Absolutely. Our Cast Concrete Colour Sample Pack (£8) uses the exact same formula as the full kits, so you can test real colour, texture, and finish before committing.

PDF Download: GFRC Precast Concrete Mould Building & Casting Instructions

GFRC Precast Concrete Mould Building and Casting Instructions

Domestic Shipping Policy: 

All orders are processed within 1-3 business days. Orders are not shipped or delivered on weekends or holidays. Once processed, orders are shipped within 2 to 5 days.

Delays can occasionally occur and this should be factored when placing an order.

If we are experiencing a high volume of orders, shipments may be delayed by a few days. Please allow additional days in transit for delivery. If there will be a significant delay in shipment of your order, we will contact you via email or telephone.

SHIPPING RATES & DELIVERY TIMES

Shipping charges for your order will be calculated and displayed at checkout. 
Concrete Lab ships to addresses within the UK. For addresses in Europe please email us at info@concretelab.co.uk. 

Delivery to Europe can take up to 1-2 week.

Delays can occasionally occur and this should be factored when placing an order.

SHIPMENT CONFIRMATION & ORDER TRACKING

You will receive a Shipment Confirmation email once your order has shipped containing your tracking number(s). The tracking number will be active within 24 hours.

CUSTOMS, DUTIES AND TAXES

Concrete Lab is not responsible for any customs and taxes applied to your order. All fees imposed during or after shipping are the responsibility of the customer (tariffs, taxes, etc.).

DAMAGES

If you received your order damaged, please contact as soon as possible.

International Shipping Policy

We currently do not ship outside the UK and Europe unless by prior arrangement.

RETURNS POLICY

Our Return & Refund Policy provides detailed information about options and procedures for returning your order. This can be found at the bottom of the page.

Caring For Your Concrete

We recommend that your finished concrete, whether it be microcement, cast-in-place or GFRC concrete, be sealed with our sealer according to our instructions. Please see the relevant Help Section for more information in relation to application.
We also recommend that once sealed your concrete is waxed regularly to both enhance the appearance of the concrete and to provide an extra layer of durability.

Things To Avoid

Heat 

Concrete products have very good heat resistance. However, as with natural stone materials, they may be damaged by sudden and rapid temperature changes so we recommend not putting pots and pans straight onto the surface.

Scratching 

Using sharp objects directly on your concrete countertops products will damage the sealer, and doing so may dull your knife, so always use a chopping board on top of your countertop.

Staining

Our high performance sealer performs very well but reasonable care should be taken to minimise the risk of staining. For the first 28 days after installation the concrete may be more susceptible to staining until it has fully cured.  Any spillages must be cleaned up as quickly as possible. The applied sealers will slow the penetration of the spillage to allow time to clean it up. If spillages have been left too long and have stained, the areas may need to be cleaned with specialist cleaners/degreasers and sealer reapplied. Sealers may not protect against any acidic substances and if not cleaned up quickly acidic substances may etch the concrete. 

How To Care For Your Concrete

We recommend using only mild detergents and a soft cloth to clean your concrete product(s). Do not use harsh or abrasive chemicals or cleaning products that contain bleach, scouring pads or sponges as these will scratch the sealers and over time may remove them. 
We recommend that a good quality furniture wax is used to maintain the condition and continually improve the protection of your concrete.
In particular we recommend Rhoose Point Beeswax because it is food safe and entirely natural so can be used in food prep areas. This can be purchased from Concrete Lab HERE.

Application of Wax

This should be applied in accordance with our instructions. Please refer to our Help Section for more guidance.

Domestic setting - In the first month the wax should be applied weekly. After this initial period the wax should be applied monthly to ensure protection.

Commercial setting - In the first month the wax should be applied twice weekly. After this initial period the wax should be applied every two weeks to ensure protection.

Reapplication of Sealer

The top layer of the sealer may eventually give way. In this event the top layer of the concrete can be lightly sanded back and the sealer re-applied.