#Patio slab crack repair how to
#Patio slab crack repair cracked

We use three different types and we have listed them below with a short summary on how each one works. Once the crack or hole is opened up so all of the damaged area is removed and you have found solid sides, you can look at which repair product to use. This is really important as any tiny piece of concrete left in the crack will prevent the epoxy mortar from bonding to the entire surface area of the crack. Open the crack so it is about 25-50mm wide and at least 75mm deep unless of course the crack does not go down that deep!ĭon’t go too mad though epoxy repair mortar is expensive and there is no need to use more than you have to. Make sure you are wearing all the appropriate personal protection equipment (PPE).

#Patio slab crack repair how to

We either find something that can be guaranteed to fill up even the tiniest of cracks or we make the cracks bigger!Ĭhoice one is not plausible given that even the finest mortar or concrete mixture will clog in small crevices, so choice two it is.īorrow (or hire) a concrete breaker and read our page on how to use a Kango Hammer or concrete breaker where you can also see a video on how to use the concrete breaker. Having explained, in reason one, above, that normal concrete has too large an aggregate to push into tiny cracks we are left with two choices.

#Patio slab crack repair cracked

How do I Repair Cracked and Broken Concrete? You can view their products here and read how we got on with them in our Product review section, subsection Building. They specialise in repair products either on the ground or on the roof. The type of repair mortars we like to work with at DIY Doctor are made by a company called Rizistal. How to repair holes in concrete with epoxy repair mortar Unless the crack or hole is more that 1 cubic foot or 0.1 cubic metres, the correct method of repairing damaged concrete is with an epoxy repair mortar. It does not matter whether this is a concrete path, slab, base or drive. What Should I use to Repair Cracked Concrete Properly?Ĭracked concrete is not properly repaired with more concrete or cement mortar. This process is called Freeze-Thaw action and more about this can be seen on our p[roject page on freeze-thaw action on masonry. Incidentally, this is the reason why you see the surface of a lot of bricks and render “blown” off. The expansion of the ice introduces more/larger cracks into the concrete which, in turn, fill with water.

This new crack lets water in which, in very cold weather, freezes.Ĭoncrete and brickwork can be damaged badly by Freeze-thawĪs water freezes it expands into ice and, as those who have seen Titanic will know, ice is a pretty unstoppable force. This leaves another crack, albeit a very small crack. As it shrinks it pulls away from the edges of the crack it is supposed to repair. All you can see is, that the top of the crack is indeed repaired, but 1mm below the surface, you very likely have the void still in place. The concrete or mortar mix cannot be forced down into small cracks or fissures easily and you cannot be certain you have even filled the crack. Repairing concrete in small areas cannot easily be done with a normal concrete mix as the aggregate is usually too large for small areas and the stones in the mix make it very difficult to get a good finish.This does not work for two reasons.Ĭoncrete paths crack easily if not laid properly The perceived wisdom out there is to look at a crack in a concrete path or drive and try to force some kind of cement based mortar or concrete into the existing crack. Repairing concrete is not as easy as one might think.