Block Paving Driveway Kerb Setting

[Steve1309]

Hi,

 

I had my worn out concrete driveway replaced with block paving and extended into some of the adjacent front garden to create a bigger driveway. After a short while, some of the kerb blocks on the edge against the lawn have come loose as cars have nudged or gone over them. It's obvious that the kerbs were just set on a thin bed of mortar and haunchings, on top of the compacted sand which ran right up to the edge of the lawn. Clearly this isn't going to be strong enough and and weight on the kerbs is going to punch them into the underlying mortar and sand. I know this hasn't been done properly and I think I know how it should have been done. 

Is there a simple way to fix this? What should I insist the contractor does to fix this properly? To me it looks like the simplest fix is to remove all the kerbs, take out the compacted sand down to the base aggregate, fill with a fine concrete to create a bed for the kerbs to be reset upon?
Your suggestions appreciated, thanks

[Carrerahill]

37 minutes ago, Steve1309 said:

Is there a simple way to fix this? What should I insist the contractor does to fix this properly? To me it looks like the simplest fix is to remove all the kerbs, take out the compacted sand down to the base aggregate, fill with a fine concrete to create a bed for the kerbs to be reset upon?
Your suggestions appreciated, thanks

Simple, yes, but it will be time consuming. It needs to be lifted and reset to the highways standard. If this was done by a civils contractor to make it vehicle proof it would be fully bedded and haunched in concrete. 

 

I'd dig it out and down so that the bedding material can be at least 100mm deep under the kerb. So fully bed them in concrete complete with full haunching to the rear to support and ideally a lower huanching would be created to the front too, but that would mean lifting the paving in a section to get access. The lower hauching to the front is to allow for tarmac, concrete, paving etc. 

 

 

Edited July 4, 2022 by Carrerahill

[Temp]

Great site for all things paving and drainage.

 

https://www.pavingexpert.com/blocks04

 

 

 

 

"Unacceptable construction"...

 

 

 

See the accompanying text if you want to argue with a contractor.

Edited July 4, 2022 by Temp

[Steve1309]

Thanks Temp for your advise.

 

This is what I have, the edge course and kerb sitting on the bedding with just a haunch to keep it together. Are you suggesting as a minimum, to remove the kerbs and bedding underneath, down to at least 100mm and fill with concrete into which set the kerbs with a haunch?

 

Thanks again

 

 

[Carrerahill]

13 minutes ago, Steve1309 said:

Thanks Temp for your advice.

 

This is what I have, the edge course and kerb sitting on the bedding with just a haunch to keep it together. Are you suggesting as a minimum, to remove the kerbs and bedding underneath, down to at least 100mm and fill with concrete into which set the kerbs with a haunch?

 

Thanks again

 

 

It seems you have completely ignored what I wrote, and asked, what I have already explained, what to do...

 

The whole lot needs to be bedded and surrounded by concrete to lock it in. If you leave it as it is and just add more haunching you will be wasting your time.

 

 

Edited July 4, 2022 by Carrerahill

[Steve1309]

Apologies Carerahill I replied to the wrong reply. I haven't ignored your advice, I am very appreciative, I just wanted to be clear as to whether the kerb and edging blocks need to be lifted or just the kerbs. Thanks again

Edited July 4, 2022 by Steve1309

[Carrerahill]

12 minutes ago, Steve1309 said:

Apologies Carerahill I replied to the wrong reply. I haven't ignored your advice, I am very appreciative, I just wanted to be clear as to whether the kerb and edging blocks need to be lifted or just the kerbs. Thanks again

You might get away without lifting the edging blocks, the main vehicular load when struck is trying to push them back, if they are dampened first and the concrete is not too dry, then a good bond should form and key it all in, in which case it should be OK for low level impact on a private residential drive.

 

In an ideal world though, it would be haunched both sides, albeit the front face less/lower. 

Edited July 4, 2022 by Carrerahill

[Steve1309]

Thanks @CarrerahillYou've confirmed what I thought should be done to fix. I don't hold out much hope of getting the original firm to come back and do it properly and will probably end up paying someone else to do it properly or doing it myself.

[Carrerahill]

13 minutes ago, Steve1309 said:

Thanks @CarrerahillYou've confirmed what I thought should be done to fix. I don't hold out much hope of getting the original firm to come back and do it properly and will probably end up paying someone else to do it properly or doing it myself.

If you end up needing to pay someone, and you chose to DIY it, I would be tempted just to mix up some concrete and bulk fill the back of the kerbing. Would just be material cost, and time, if you have any spare.

 

If it was me and the installation generally looks smart, and I was going to need to DIY it, I would dig out the back, chip down to the same line as the bottom of the kerb, clean it all so adhesion is good, I would even probably PVA the back of the kerbs (total overkill but that is me) then tip in bulk concrete then haunch it neatly with a trowel. That would lock it into place and the PVA would help get a really good bond between the concrete and the kerb to essentially "glue" it into place.

 

Mortars and concrete have no shear strength, however, in practice I have seen plenty of blocks and bricks and other masonry products which have been bonded together with mortar or concrete so strong that the masonry product breaks before the bond. So it is possible to lock something in place albeit not the "right" way.

 

Make the concrete with a bit extra cement and not too dry, the extra cement and water will make a nice paste which will make contact with the kerb and make a good bond.

 

Edited July 7, 2022 by Carrerahill