How to replace driveway drain?

[thomason_peter1]

Hi.I need to replace a grated driveway drain in my driveway. How wide should the cut/ concrete be either side of the new drain (to create the new 'concrete walls')?

Also should there be expansion cuts between the existing drive concrete and the new concrete?

 

[thomason_peter1]

Photo with old drain removed.

[JacobZ]

Hi @thomason_peter1,

A warm welcome to the Bunnings Workshop community and thank you for your question.

Is the plan to install a wider grate than was there before? Or simply to install the same size grate?

Everhard Industries are our main suppliers for drainage grates and their Installation Instructions provide details on installation.

They recommend using 10mm thick expansion foam such as this Sika 10x75mm Abelflex on either side of the drainage grate to allow for expansion and contraction of the concrete. With this being said, the channel should be cut so that it is 20mm wider than the channel you are installing.

With the foam, there is no need for expansion cuts.

Let me know if you have any further questions.

Jacob

[thomason_peter1]

Thanks!. The drain channel i will be using has 25mm sides polly-crete with gal. Grate (not the thin black poly/plastic) - and I am looking at 75mm or 100mm wider cut/concrete on each side of supplied drain channel to drop in and fill -so seems either will do/plenty?

Also what strength concrete is required for  e.g high strength or regular?

Thanks

[JacobZ]

Hi @thomason_peter1,

Unless the concrete on either side of the grate is compromised, you don't really need to widen the trench by so much. I'd suggest checking whether the manufacturer of your specific grate has an installation guide with details of their specific product. They will have an advised method of installation that should be followed to ensure compliance with the terms of their warranty.

As driveways will have vehicles driving over them, you'll want to use high MPa concrete. The MPa (megapascals) rating tells you the compressive strength of the concrete and when the concrete needs to support heavy loads, such as vehicles, having higher compressive strength is certainly worthwhile. This Dingo Hi Strength Concrete is a good option.

Let me know if you have any further questions.

Jacob