The Brew Cabin

Hi
i am living proof that being unaware of the advice on this website can cost
a contractor laid paving on my property by laying the blocks first, and then the edge course last, with about one inch of haunching
consequently as stated here numerous times, the one inch haunching has fell off the sand, and the edge course is opening out, and the blocks are moving under foot
he has promised to rectify it, what guides can i use and what should i look for in the rectification, bearing in mind the blocks are already down and i am trying to recover from what i have now, to getting a decent paved area.
thanks for a great site
griff

The existing edge courses should be lifted out and set aside for re-use, along with the first 300-500mm of paving, depending on the pattern of laying.

The bedding and part of the sub-base should be excavated to make a channel that is [width-of-edge-course + 125mm] wide and [depth of block + 75/100mm] deep, below finished paving level.

The edge-course blocks should then be re-laid on a concrete bed 75-100mm deep. The concrete should be roughly C20 strength (1:2:4 roughly). Once laid and aligned, the edge-course blocks should be haunched with not less than 100mm width of backing concrete, as shown on the edge courses page of the main website.

Any concrete extending from the front edge of the edge-course blocks into the body of the pavement should be trimmed off so that it is more-or-less flush with the face of the blocks.

Ideally, the edge course should then be left for 24 hours to allow the concrete to set, whereupon the sub-base and bedding of the body paving can be re-placed and prepared before re-laying the blocks and cutting-in as required. The blocks can be compacted with the vib plate, but it's best to try and keep the plate off the edge course, as the concrete will still be somewhat 'green' and liable to give way under pressure. However, once the consolidation and jointing is complete, the paving can be trafficked immediately, although it's best to keep away from the edge course for 3-7 days until the concrete has set more fully.

How's that? :)

many thanks for the prompt reply
doubt if the contractor will do that,
but at least i can comment now with a bit more knowledge
all the best
griff

well the marshalls representative and contractor came out this 8.30 this morning (ground frozen!)
basically the marshall's representative confirmed to me and the contractor that;

1) there is no requirement to bed the soldier course on concrete where the soldier course butts a wall or house side, whacked sand is okay, this applies to the entrance of the drive as well, where the cars run over

2) for the driveway, the minumum cement bedding for the soldier course where no side restraint other than grass; is to a depth of 40 mm (the area occupied by sand) on top of the sub base and no deeper into the soldier brick wider than half brick or 3 1/2" in from the outer edge

3) for the driveway, the haunching is okay, if it is a third to halfway up the soldier brick side, and slopes down at 45 degrees from the brick side

4) there needs to be no side restraint haunching on pathways as long as the whole soldier is laid on cement

5) it is okay for the setts to move under your feet when you walk over them, they just need more sand in the joints

as the expert, it is difficult for me to doubt him, but three hours later the sun is up, and guess what, some soldiers are now starting to move under my feet.

life is great!

1 - The Rep is right about a concrete bed not being essential against a wall, but it doesn't half make the job easier to do it that way. However, to suggest that no concrete bed is needed at the drive threshold is WRONG and you can tell him/her I said so.

2 - I'd disagree with the figure of 40mm minimum. BS7533 Part 3 shows an approved construction for edge courses, and the concrete bed is a damned sight thicker than 40mm! It extends well into the sub-base layer, and, although no dimensions are given, it's safe to assume that it is the 'industry standard' minimum bed of 100mm.

3 - I'm not sure what you mean by 'brick side'. Doi you mean the side of the block? If so, I don't know where this Rep has got that information, as the construction drawings defiitely show the haunching coming to two-thirds block depth.

4 - Bollocks. ALL edge courses laid to free edges require a haunching, whether it's a driveway, pathway, patio, bus lane or high street. If the Rep has told you this, get it in writing and I'll lay a pound to a penny that Marshall's deny it.

5 - This is possibly true when the paving is new, but it shouldn't be so a few weeks down te line, not with the weight of an avergae pavement. There will be some movement under vehicular traffic, but not from foot traffic.

Once again, this sounds like the Rep siding with the Contractor in an unbalanced assessment. You should insist on a written report, just in case anything goes wrong at a later date. I'm particularly concerned about the advice regarding the ability to omit haunching.