Saw cutting is a process whereby very specific and controlled cuts are made into concrete using specialist electric saws or wall saws. These cuts are called control joints. These control joints are essentially there to control the location and direction of the cracks which inevitably form in concrete soon after it is poured and set due to shrinkage. This shrinkage occurs as the concrete hardens and the moisture in the concrete dries off.
You can’t stop the formation of cracks in new concrete altogether, but with the proper use of saw cutting you can ensure the cracks are where you want them to be, and not randomly scattered through your concrete slab.
It is an extremely useful process in most construction jobs involving concrete, but it is highly specialised work and if done wrong it can do more harm than good. Some of the most common pitfalls in saw cutting are:
Saw cutting at the wrong depth
If you cut too deeply you can compromise the strength of the concrete, and if your cuts are not deep enough it could be too shallow to function as a control joint. This would mean random cracking would still occur.
Saw cutting too soon
If the control joints are cut too quickly after the concrete is poured, it could result in ravelling. This means the concrete isn’t yet strong enough for effective saw cutting, and will leave an unsightly jagged edge to your cut.
Saw cutting too late
If you cut your control joints too late after the concrete is poured, the concrete will have hardened too much and you can end up creating even more random cracking than you would have otherwise.
Saw cutting is best done roughly 4 or 5 hours after concrete is poured, but this depends on a lot of different factors including weather and variations in concrete composition. This is just one of the reasons why saw cutting is a job which is often best left to the experts.
So why use saw cutting?
The benefits of saw cutting are tried and tested, and there are plenty of them. The main benefit of avoiding random and uncontrolled cracking through your concrete as it hardens is extremely important, as without saw cutting your construction project could be compromised before it has even begun.
Saw cutting also allows for your concrete to shrink and swell through temperature fluctuations without causing structural damage. This is particularly vital as we see more and more varied and extreme weather and temperature changes across the UK and further afield.
If you want help with a saw cutting project, or to discuss options, please get in touch with us today. Our team of experts have over 30 years of experience and are more than happy to help.