Fixing a low spot - bed preparation 

Yet my own driveway, 26 years old, has not a single lowspot, and the 100m² or so requires a total of around 20 mins maintenance a year. When properly laid, I *still* believe block paving represents the best value-for-money paving of the lot.

It's all explained on the web page supporting this video. It's only the laying course sand that is replaced, not the sub-base, and it's replaced because all those years of trafficking will have had a crushing effect which will have impacted on the performance of the sand, reducing both its interlock and free-draining capability due to the enhanced proportion of fine material. This repair is in full compliance with the relevant British Standard and the Interpave Code of Practice documents.

@@TonyMcCormack what a load of bollox when a drive is laid you compact the sand with a wacker plate so what does that do? Complete nonsense.

I’ve laid plenty on top . No issues. Remember the sand is the same age under the non sunken areas. So it’s performing fine.

No. As explained in other replies, and on the website, the sand becomes crushed and its performance deteriorates over time so, whenever re-instating a pavement more than around 12 months' old, the sand (or other laying course material) should be completely replaced, as required by the relevant British Standard

He aint got a clue mate stamping it with the feet would send alarm bells ringing for me.🤣🤣🤣

The reasoning is explained on the accompanying webpage - www.pavingexpert.com/refurb_04

@@TonyMcCormack thanks. Great explanation 👌

No - it's not a damaged underground pipe. It's just a bit of bed settlement, which is not uncommon on a 20-year old pavement. Settlement from broken pipework is usually much more obvious.

Compare in what way? Sharp sand has been the preferred laying course medium for many years. 2-6mm grit is more commonly used with permeable CBPs. It doesn't compact to the same degree but it is far more free-draining

I don't get involved in pricing as I don't take on the work, but if you assume a couple of (very leisurely) hours for a tradesman, then maybe 150 quid.....ish

The full details of this section of the project are provided on the webpage listed in the description above - www.pavingexpert.com/refurb_04.htm#bedprep - it's a coarse Class 2 grit sand

It sounds as though your man never compacted the sub-base sufficiently. That's the usual cause when modular paving settles so soon after completion, and the car running over it would be enough to hammer it dwn that bit further until it reaches the 'point of refusal', which shoud have been achieved during construction. So, yes: the method shown in the video should be satisfactory as long as the settlement is no more than 25mm or so. As for the paving beneath the tap, I,d tend to agree with the suggestion that the paving there should have been laid on a semi-dry mix, just to prevent the inevitable dripping and sploshing from washing-out the sand bed. Again, you can use the above method but this time use an 8:1 mix or a 6:1 mix of coarse sand with cement as the bedding beneath the tap area and for about 300mm in each direction around it. The black dolomite is a form of limestone but we don't see it often. Whereabouts are you?

Tony McCormack hey tony thanks for responding so quickly.Actually I am in Consett Co Durham maybe a bit to far for u. At the moment I am trying to get the guy back who done the job but tbh I dont think he is interested as he did the job last Dec and he said he was back to contract work until april then I messaged him and he said he was behind dont worry I will get to it .its an easy fix etc so I gave him till now to text him and he hasnt responded so I will call him on Monday but you know im not an expert but I can do bit .I did the relaying of my blocks in my back garden but as he did the front drive job I would rather him do it as I wont have to pay him and he has a 10 year guarantee. But cos he wont get paid he aint interested .Well thats what I think .Ateotd I would rather someone pro do it even if I have to pay again just a little bit but u r to far . Can I send u a pic maybe on messenger or wassap or something. i forgot ye u know the levels around the tap grate were based on the slight gradient of the drive from the garage pin kerb to the pavement pin kerb so Im not sure how much play I have to lay some concrete and then the sharp sand that the blocks lay on. thanks again mate really

I forgot Tony but do i think that black stuff he used was bad quality and thats y it sunk aswell .Strange but the rest of the drive is ok although now I park the car in different places to avoid the weight on one area .Also some of his cuts against the lawn pin kerb were not gr8 .Tbh he rushed it.but if I say that to him etc he will tell me where to go and then its legal action and I cant b arsed with that

Just one more thing Tony with regards to the drive sunken tracks .If the black sub base under the sand has sunk then what is stopping it sinking again after the sand is renewed and the blocks r re layed I mean how do I sort of get a new secure level would I have to relay some more dolomite and whack it down or just use more sharp sand and whack that down

send to.... tony AT name-of-website

We did a professional repair in full compliance with the relevant British Standard. You can choose to work to lower standards, if you wish, but we never do.

@@TonyMcCormack I live in canada.. Just seemed like unpacking the ground only to pack it again is something I wouldn't do.. I wouldn't concider that to be lower standards by any means.. sounds more like the british standard need to be re thought.. You did do a good job..

@@Redeyedye We seem to be managing fairly well plus we have the scientific data to show our methods are valid and do actually result in superior quality remedial works.

+stclairstclair Probably to record contractors effing and jeffing as they struggle with awkward materials and know-all customers. That's why I tell my contractors to keep quiet during filming!

It's a highly effective method of lightly compacting a small area of bedding sand. Full compaction is neither required nor desirable as there has to be some "give" to settle in the blocks. Have a look at the date on that video - 6 years later and the repair is still absolutely perfect. I've been doing this for almost 50 years - give me some credit for knowing what I'm doing!

So: you obviously have zero understanding of unbound construction of block paving but don't seem to mind letting everyone know. Brave!

With over 50 years experience in the trade as a professional paving installer, and full compliance with the relevant British Stadards, yes: I reckon I do know what i'm doing. Do you?

Take it up to where its not sunk then get some 4x2 notched either end to allow compaction then screed it nice and flat then relay it. Also why take original sand out that been compacted for years?? Just add more. But 50 years doing it you'll know anyway.

@@grahamdalzell6933 You've not read the British Standard, then. If and when you do, you'll find that the methodology shown is wholly in accordance with that document and is considcered "Best Practice".

@@TonyMcCormack does it say to stomp the sand down with your feet 🤣🤣🤣🤣

@@grahamdalzell6933 Buy your own copy of the British Standard and find out.

You're wrong. Sand *does* break down, and the laying course sand beneath block paving gets crushed to the point of being too fine to be of any practical use. Further, if you care to read the relevant British Standard and the Interpave documentation regarding reinstatement of block paving, removal and replacement of old sand is regarded as essential to effect a thorough and reliable repair.

You obviously know nothing about geology. Show me one article on sand breaking down. Go ahead and google does sand break down, go ahead. You won't get anything cause it doesn't. Sand erodes, meaning it washes away, but it doesn't break down. If you mix sand with dry concrete it stops the erosion process considerable. As I said you wasted a lot of time, and your british standard is dumb!

You're obviously far more familiar with paving in Britain and Ireland than anyone else, including all of the BS committee responsible for that standard, with their meagre 1500+ years of experience in the paving industry. I shall ask them to contact you so you can re-educate all of us with your exacting knowledge and scathing wit. We must bow to your superior knowledge. I'll also let the MIneral Productrs Association know that the crushing equipment which their 100+ members use to create the specialist sand we use for paving, cannot possibly work because the great Tom says sand can't be broken down. To think we've been getting it all so wrong for so many years. We are, indeed, in your eternal debt.

You have a BS committee? LOL!!!!!! That should tell you something. Glad I could get their 1500 years of experience up to the 21 century. Referencing Stonehenge in all their documentation seems a bit outdated don't you think? So glad I could be of help old chap.

Tony McCormack Strange, but I recently releveled areas of my paved patio and the sand looked as coarse as the day when it was initially installed ten years prior. I didn't use any new sand and the areas that were reworked seem to be holding up fine.