Serving London and the South East of England β professional, dust-controlled joint cutting by an experienced, accredited specialist contractor.
in a hurry? Call us now: π 020 3286 3428 / 01424 720259
Or visit us at diamonddrillinguk.com
Expansion and movement joints are one of the most important β and most misunderstood β details in any concrete or masonry structure. Get them right and a slab or wall can move, breathe and settle without cracking. Get them wrong, or leave them out altogether, and you end up with random cracking, spalling and expensive remedial work down the line.
At Diamond Drilling UK Ltd we cut expansion and movement joints into concrete slabs and into block and brick walls across London and the South East. This guide explains what these joints do, how they are cut into floors and walls, and β crucially β why this is a job for a professional diamond cutting contractor rather than a general builder with an angle grinder.
What Are Expansion and Movement Joints?
The term βexpansion jointβ is used loosely on site, but there are really three distinct joint types, and knowing the difference matters for both performance and cost:
β’ Control (contraction) joints β sawn into a slab to create a deliberate weak point, so shrinkage cracking happens neatly along the joint rather than randomly across the surface.
β’ Expansion (movement) joints β designed to absorb thermal expansion and contraction, allowing the concrete or masonry to move without stressing the surrounding structure.
β’ Isolation joints β separating a slab or wall from a fixed element such as a column, wall or machine base so movement in one does not damage the other.
Whichever type your project needs, the principles are the same: the joint must be cut in the right place, to the right depth, at the right time, and with a clean, straight, accurately controlled cut. That is exactly what specialist diamond cutting equipment is built to do.
Cutting Expansion Joints in Concrete Slabs
In floors, driveways, warehouse bases, car parks and industrial slabs, joints are cut using a floor saw fitted with a water-cooled diamond blade. Precision and timing are everything:
β’ Timing β control joints in a fresh slab are typically cut early, before uncontrolled shrinkage cracking has a chance to start. Cut too late and the crack has already chosen its own path.
β’ Depth β joints are cut to a specified proportion of the slab depth so the slab is encouraged to crack cleanly beneath the joint. Too shallow and it fails to control the crack; too deep and you risk weakening the slab or striking reinforcement.
β’ Spacing and layout β joint spacing is set out to suit the slab thickness, mix and use, keeping panels regular and the finish professional.
β’ Reinforcement and services β slabs frequently contain steel mesh, rebar, post-tension cables or buried services. Cutting to a controlled depth avoids costly and dangerous strikes.
We also re-cut and widen existing joints, and cut new joints into established slabs where movement problems have appeared β all with full water suppression to keep dust and slurry under control.
Cutting Movement Joints in Block and Brick Walls
Joint cutting is not just a floor job. Blockwork and brickwork move too, and long runs of masonry without adequate movement joints are a classic cause of vertical cracking. We cut clean, straight movement joints into block and brick walls using wall (track) saws and ring saws, both of which are designed to cut deep, precise lines through masonry and reinforced concrete.
New-build and designed-in joints
β’ Cutting continuous vertical movement joints at the centres specified by the engineer or designer.
β’ Achieving straight, full-depth cuts that a hand-held grinder simply cannot deliver cleanly or safely.
Retrofit joints into existing walls
β’ Introducing movement joints into existing block or brick walls that were built without them and are now cracking.
β’ Cutting to a controlled line and depth so the wall is relieved of stress without compromising its structural integrity.
Because ring and track saws are water-cooled and dust-suppressed, we can carry out this work inside occupied and finished buildings with far less mess and disruption than traditional methods.
Why It Is Important to Get the Professionals In
Joint cutting looks simple. It is not. A poorly cut joint can be worse than no joint at all, and the risks of getting it wrong fall into four areas:
β’ Structural integrity β cut too deep, in the wrong place, or through the wrong element, and you can weaken a slab or wall rather than protect it. Depth, position and timing all have to be right.
β’ Hidden reinforcement and services β rebar, mesh, post-tension cables, conduits, gas, water and electrical services are all lurking in modern construction. Professional cutting reduces the risk of a dangerous or expensive strike.
β’ Silica dust and health & safety β dry-cutting concrete and masonry releases respirable crystalline silica, a serious health hazard. Our water-cooled diamond equipment suppresses dust at source, protecting your site and complying with HSE expectations.
β’ Finish and accuracy β diamond cutting delivers dead-straight, clean, consistent joints. A wandering grinder line looks unprofessional and rarely performs as intended.
Bringing in a specialist means the joints are cut once, correctly, safely and cleanly β protecting both the structure and everyone on site.
Why Choose Diamond Drilling UK Ltd?
Diamond Drilling UK Ltd is an experienced, accredited diamond drilling and concrete cutting contractor based in Sussex, with a London office in Hatton Garden. We specialise in diamond drilling, concrete cutting, sawing and chasing, and we work daily across London and the South East for main contractors, builders, developers, facilities managers and homeowners.
β’ Specialists, not generalists β diamond drilling and cutting is what we do, all day, every day.
β’ The right equipment for the job β floor saws for slabs, wall (track) saws and ring saws for walls, all water-cooled and dust-controlled.
β’ Trained, experienced operators β accurate setting-out, controlled cutting and a tidy, well-managed site.
β’ Full coverage of the South East β from our Sussex base and London office we reach jobs across the region quickly.
β’ Straightforward to deal with β tell us about the site, access and the work you need, and weβll come back to you fast with a clear price.
Areas We Cover Across the South of England
From our head office in St Leonards-on-Sea and our London office in Hatton Garden, we cover London and the wider South East, including:
β’ East Sussex β Hastings, St Leonards-on-Sea, Eastbourne, Brighton, Bexhill, Lewes, Hailsham and Crowborough.
β’ West Sussex β Worthing, Crawley, Horsham, Chichester, Bognor Regis, Littlehampton and Haywards Heath.
β’ Kent β Maidstone, Canterbury, Ashford, Tunbridge Wells, Dartford, Gravesend, Sevenoaks and Folkestone.
β’ Surrey β Guildford, Woking, Epsom, Redhill, Reigate, Camberley, Staines and Leatherhead.
β’ Greater London β the City, Central London, Hatton Garden, Croydon, Bromley, Kingston and Richmond.
β’ Hampshire β Southampton, Portsmouth, Basingstoke, Winchester, Farnborough and Aldershot.
β’ Berkshire β Reading, Slough, Bracknell, Maidenhead, Windsor and Newbury.
β’ Buckinghamshire β Milton Keynes, High Wycombe, Aylesbury, Amersham and Beaconsfield.
β’ Oxfordshire β Oxford, Banbury, Bicester and Abingdon.
β’ Hertfordshire β Watford, St Albans, Hemel Hempstead, Stevenage and Hertford.
β’ Essex β Chelmsford, Colchester, Basildon, Southend-on-Sea and Brentwood.
β’ Dorset β Bournemouth, Poole, Weymouth, Dorchester and Christchurch.
Frequently Asked Questions
What is the difference between an expansion joint and a control joint?
A control (contraction) joint is cut to guide where a slab cracks as it shrinks, keeping cracking neat and predictable. An expansion (movement) joint is designed to absorb thermal expansion and contraction so the structure can move without stressing itself. Many projects use both.
When should joints be cut in a new slab?
Control joints are usually cut early in the slabβs life, before uncontrolled shrinkage cracking begins. The exact window depends on the mix, conditions and slab, which is why timing is best judged by an experienced cutting contractor.
Can you cut movement joints into an existing brick or block wall?
Yes. Using wall (track) saws and ring saws we can retrofit clean, controlled movement joints into existing masonry that was built without them and has started to crack, relieving stress without compromising the wall.
Do you control dust when cutting?
Yes. Our diamond saws are water-cooled, which suppresses respirable silica dust at source and keeps sites cleaner and safer β essential inside occupied or finished buildings.
Which areas do you cover?
London and the South East, including Sussex, Kent, Surrey, Hampshire, Berkshire, Buckinghamshire, Oxfordshire, Hertfordshire, Essex and Dorset β essentially most of the south of England.
Get a Quote from Diamond Drilling UK Ltd
Need expansion or movement joints cut into a slab, or into block or brick walls? Tell us about the site, the access and the work you need, and weβll come back to you quickly with a clear price.
Diamond Drilling UK Ltd π 020 3286 3428 / 01424 720259
π§ info@diamonddrillinguk.com
π www.diamonddrillinguk.com
East Sussex Office: 215 Harley Shute Road, St Leonards-on-Sea, TN38 9JJ London Office: Unit 34, 67β68 Hatton Garden, London, EC1N 8JY
For diamond drilling across the South East β there is only one call to make.
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