When it comes to float finishing, again, we did this on the test panels, but the contractors found that floating brought too much finer material to the surface, depressing the larger aggregate, which spoiled the finished (exposed) appearance. By using a relatively high slump concrete (75mm - sloppy, in non-trade parlance) they found that a light tamp to level the concrete and then one pass of a lightweight aluminium vibrating screed was ample to accurately level the concrete without losing the larger aggregate.

Once the Rugasol had been sprayed on using a standard hand-worked Garden Sprayer (from what I saw of them) it was left for 4-6 hours and then washed off using a power-washer on a lower-than-normal pressure setting. They found that the usual power setting was blasting out too much of the aggregate, and so they 'tweaked' the lance, somehow, to get a wider spray pattern at a lower pressure.

Have you considered using a resin-bound system over the concrete? It's not frighteningly expensive (if you use a scattercoat system) and would give you the look you like without risking problems or exposed base concrete.

As for a kerb - use whatever you want. The chepest would be a plain concrete road kerb of some type laid and haunched on a C20 concrete bed. However, for a decent-looking driveway, perhaps one of the coloured block paving kerbs would be more attractive?

I can't see how that would be any better than the concrete base, to be honest. It's a rigid base, with no give, so the added gravel has no chance of 'bedding itself in' and thereby reducing the risk of scuffing and exposure.

Again, if you have a decent tarmac base (or concrete) one of the Resin Bound systems might be worth considering.

Anyway, laying gravel over such a surface would be slightly more successful than laying it over a plain bitmac or concrete base, but not dramatically so. You still have the core problem of persuading a loose material to stay put on a hard, monolithic surface, so, as mentioned earlier, the use of additional 'fines' would definitely be beneficial, but don't expect miracles.

Turning to the Ronadeck Fast Grip, as far as I know, and Simeon will correct me if I'm wrong, you can buy just the resin and select your own aggregate (following advice from the excellent folk on the Ronadeck Tech Help Desk). I'm not sure about the price, as the guide info I have includes the aggregate and I don't have a separate figure for resin-only, for some reason. I'm sure Simeon will help....  

If there was an issue with the drains, it should have been apparent when the PIC contract undertook the preparatory work, in the form of soft ground, or wet spots, and, if such a problem was noticed, the contractor should have pointed this out to the client and priced for remedial work. That the contractor continued with the PIC indicates that their professional (!) opinion was that the ground was suitable to accept a PIC driveway and they have no real grounds to claim otherwise. Either the ground was bad (because of damaged drains) and they chose to disregard this and overlay the problem with PIC, or the ground was not bad and the PIC failed. Either way, it's their problem, as far as I can see.

Are there any control joints in the PIC?

If there is a DPM beneath the concrete, it should be evident at the edges of the PIC, as, ideally, the DPM extends beyond the area of the concrete and/or is brought up the sides of the slab. This could save the client the cost of core sampling and should earn you a free pint in the alehouse!  

Let me know how you get on.

Anyway, to you Qs...

1. - Yes. They can't be power-washed, but a garden-vac in reverse is handy for re-distributing litter and leaves. Moss and vegetation accumulate in the less trafficked areas.
2. - You can't, unless you use a binding system such as Resin or bitumen (which turns gravel into a bitmac)
3. - 5-14mm, IMHO.
4. - You'd travel many a mile and still find nowt better.

To produce such a concrete yourself, the 'basics' are covered on the Exposed aggregate Concrete page. However, you may be interested to learn that I'm advising on the import of an exposed aggregate block paver from the leading European manufacturer, and they produce their pavers in a range of 10 colours, including a golden buff and an intriguing red-gold colour they sell as 'Blossom'. These allow you to have the look of exposed aggregates, with all the hard work done for you - all you have to do is lay them in exactly the same way as you would with standard pavers.

If you want some more info on these Rockstone pavers (as they are called), let me know and I'll send you a leaflet. But if you want to knock up your own concrete, you first need to source your deco gravel. Is there anything you've seen in your area that you think would do the job?

I know what you mean about the problem getting local ready-mix suppliers to consider using anything 'out of the ordinary'. We had hell of a job getting a supplier for the slate-based concrete I designed for the National Trust's property in Beddgelert last year, and found that a small local company was much more amenable and co-operative than any of the 'nationals'.

I have been meaning to contact you regarding your NMP retarder, as this is something I'd like to cover in more detail on the website. Perhaps you can call in for a brew the next time you're hurtling through the village?

I don't have a problem in recommending SBG on relatively flat driveways. It still migrates downhill, although not as noticeably as loose gravel, and if there's a lot of traffic (relatively speaking) than it can develop potholes and bald spots quite quickly, but these are easy enough to fix.

As for a contractor....mmm. I know a couple of gangs that do driveways in that area, but they really do specialise in block paving rather than general groundworks, so I'm not sure if they'd be interested. Still, send me an email to the usual address, and I'll pass on some details.

A more-open-than-expected texture could result from inadequte compaction or using a material that has cooled too much, or a poorly graded material, but again, you'd need to employ a professional laboratory to assess the condition, and it could cost as much for the lab testing as it did for the original driveway. And, bear in mind, testing of bitmac is generally a destructive process - you end up with a damaged surface!

Remedial options include an overlay, or a resin-bound surface dressing, or even a sealing grit, but I would recommend that you speak to your original contractor and get them to provide copies of delivery notes, so that you can verify what materials were laid, and then seek their advice on how they think it would be best to proceed. Remember that the open texture will gradually fill up with detritus and all sorts of crud and, in 12-18 months time, you probably won't even notice the texture.

If you've specified a close-textured finish, then how have you quantified 'close textured'? If, however, you've specc'ed a DBM surface course, then you more or less get what what you're given.

If there was a distinct variation in texture throughout the pavement, then that could be a legitimate cause for concern, but unless a surface texture has been precisely specified (with tolerances), then deciding whether an area of surfacing is close-textured enough becomes a subjective exercise. What you define a 'some' variation another observer might define as 'minor' or 'insignificant'.

Similarly, where a diff in surface texture genuinely could be a 'problem' (defined as a potential hazard or failure) on a public highway, it is unlikely to be a 'problem' (same definition) on a residential driveway. Aesthetically, it could be a "problem", but structurally, it's unlikely.

This is all getting to be terribly semantic - have you discussed this with your contractor? They have the advantage of being able to see the 'problem' and, if necessary, quantify it using an appropriate test method, whereas I'm working blind!

I've always found that laying these things (you call them Pamments, but we call them Tiles or Pavers) it's best to use a semi-dry bed rather than a fully wet mortar. Use 6 parts grit sand to 1 part cement, and add just enough water to bind the lot together. The usual test is to squeeze a handful of the mixed product in your hand and check that there is no water dripping out. This consistency makes laying much easier, while ensuring a firm bed for the Pamments, and it makes an ideal base for the mortar jointing - see the Pointing Case Study page for a guide to the simplest, reliable pointing method.

Anyway, to your site access road. The simplest solution is to lay a geo-fabric of one kind or another, and then put 150mm of DTp2 or Crusher Run over the top of it. If you use a meshed geo-fabric, like one of the Tenax grids, then wagons would have no trouble tracking over it, and, at the end of the job, the stone can be scraped off, the geo-grid recovered, and used again on other projects.

Putting down 100m of concrete, assuming it to be around 3m wide and 150mm thick, cubes up to 45m³, and even if you can get it supplied to site and laid for around 90 quid per cube, you're looking at just over 4K to put in the road, and then you've the fun of trying to get rid of it again at the end of the job!

You could probably get 60-75mm of base course bitmac for less, if the existing base is good enough to lay over, and that would also mean less stuff to get shut of when your build is finished.

As for concrete running downhill when placed, if you get a stiff slump, anything under 50mm, then it doesn't travel all that far. Use shuttering or RoadForm to contain the edges, and just run over it once or twice with the vibrating beam screed, and it should be fine. Don't forget to allow for control joints every 6m or so, or you'll end up with a knackered concrete drive after your first delivery.

Will this track form the main access to your home once all the building work is done? If so, the crushed stone over a geo-grid notion is by far the best option.

Stone isn't really "pushed off at the sides" - you do get some 'spread', but it's usally 300mm or so, not much more, and using a geo-grid helps minimise wastage.

Whichever option you go with, let me know how it works out.

You could lay unbound gravel over the area of limestone, and, once you've got rid of the bitmac, there should be a reasonable sub-base underneath that can be covered with gravel after a bit of tittivating and regulating.

If you want to overlay the existing, then bitmac is your only real option. You could then use a bound dressing, such as one of the resin-based products, on the surface of the new bitmac, which means no loose gravel to cause accidents, or you could leave it as plain, ordinary bitmac.

There is so much of what you say that really should trigger the alarm bells...

1. - weeds growing through bitmac - this only happens when there is an unacceptably thin layer of bitmac laid over a sub-grade, with no proper preparation, no sub-base, and probably no base course. Weeds simply will not grow through a properly constructed bitamc driveway. If they do, then it ain't been properly constructed.
2. - Staying off the surface for 4 days - a quality bitmac surface can be trafficked in 4 hours, not 4 bloody days!! Another classic indicator of the cowboy operator - "Don't drive on it until the cheque clears"
3. - Puddles - poor workmanship, but probably due to non-existent sub-base and/or base layer.
4. - Offer to pull out weeds - how will this improve the integrity or life-span of the surfacing? It's purely cosmetic. If there're weeds there now, then there'll be even more next year, and more the year after that and...

You need a detailed report on all the problems with the drive, and then request that the original contractor comes back, removes the crap they've dumped on you, and installs a new driveway, constructed to agreed standards, including edging kerbs, sub-base, base etc. Give them a time limit of not more than 4 weeks and inform them that, if they are unable or unwilling to do this, then you will bring in another contractor to carry out the works and pass on the bill, plus inconvenience and administration charges from yourself, to the original contractor.

CC to Trading Standards and your solicitor.

I wish I could offer you some hope, but I doubt you'll get anywhere, and, even if you take court action, it'll be 3-4 years before you get a non-enforcable ruling in your favour.  

I can't think of anyone in the Middx area that does driveway reports on bitmac surfacing. If you contacted the Institute of Asphalt Technology in Surreyshire (01306 742792) they might be able to suggest someone, but it won't be cheap. The trouble with bitmac is that it's more commonly used for civil and commercial projects, rather than driveways, and so it's hard to get someone willing to visit a small project such as yours. I could take a look the next time I'm down in the wilds of Middlesexshire, but that could be a month away.

I don't think Watchdog or Rogue Traders will be all that interested, as they recently did a prog on the Tarmac Tinkers, but your local paper might be interested as it's a local story and would be a valuable warning to other Ashfordians. Bear in mind, though, that if you publicly slag off this company, it makes legal action that much more complex. Do the threatening letter first, and then see what response you get, if any.

Anyway, on with your questions...

The 'line' down the centre is probably a day joint. These are formed when a wide area of bitmac is being laid, so that the area is broken up into more manageable 'chunks'. You can see them on almost any main road or motorway, as they are formed at the outer edge of the screed of the paver machine.

However, for a driveway, they are unusual, unless, as I said, there is a particularly wide area. As a rough rule, I wouldn't expect a day joint in hand-laid bitmac unless the width was in excess of 6m.

As for the spec - there's a standard spec for a residential bitmac driveway on the Specifications page, but there are so many different macadams on the market that giving an absolute spec is well nigh impossible.

It might be best to give me a call to discuss this further. 01925 762034 from around 11am (the tablets are working by then) up until 4pm (when The Reichskinder return from school) is the best time to catch me. I may be in/around London village this coming week, but I'm not sure just yet. I have over 1,000 emails to plough through, and a tower of unopened mail that is currently defying the laws of gravity by tottering and swaying on top of the kitchen table, so I'm not sure when (or even IF) I'll ever get out of here again!  

One local authority in the north of England has implemented a great scheme to combat the tarmac cowboys - none of the batch plants in/around the city are allowed to sell bitmac to unlicensed casual callers. This has resulted in the cowboys being more or less excluded from their source of materials and has reduced the number of complaints to the local TS. If only I can convince other Local Authorities to follow their example!

90mm is more than enough for a domestic driveway. We mnormally recommend 50+25, so, even if you do get only 70mm at the edges, it's not all that bad, but, as I said, if you're paying for 90mm, you should get 90mm.

I didn't check the Brew Cabin over the last 3 days as I was away at the funeral of a friend, so I hope you've managed to get some sort of resolution by now, but please let us know how you got on.

However, if you're on a 'fixed price' deal, then the contractor may have you by the short and curlies and might expect you to pay the agreed price regardless of their input, materialwise.

Get it agreed with them before they start work. If they are going to be charging the same price, then insist they supply the full 60+30 spec...that should encourage them to offer a reduced price.  

Send me the name of your contractor, Robin, and I'll add them to the little black book I keep.  

I can't understand why a membrane has been placed on top of the sub-base - if a membrane was necessary, then the place for it would have between the sub-base and the sub-grade. It's doing nowt sitting on top of the sub-base!

The proper construction for your driveway, as shown on the Gravels page would be summat like 100-150mm of DTp1, with an optional Terram 1000 membrane beneath it, and then 20-35mm of your chosen gravel on top of the sub-base.

I'm guessing that your contractor hasn't constructed many gravel driveways in the past, but has adapted the nonsense he's seen on one of the TV gardening programmes and hoped for the best!

Water will not wash it away - it's an oil-based product and oil and water do not mix. Your only option is to cut out the affected area and patch it with new material, much as shown in the Fuel Leak FAQ

300mm of sub-base is, however, erring on the side of caution. If there was a known problem with the sub-grade, then I could understand 300mm, but, as imported aggregates and exported spoil are now quite costly items, reducing that to, say 200mm of sub-base with a separation membrane might provide better value.

Without examining the site, I'm not in a position to say what would be most suitable, but, if your man is recommending 300mm of sub-base, then he must have a reason for so doing. Have you asked?

Unless you have a top-notch sub-grade, summat with a CBR of around 10 or higher, then I'm not convinced 150mm of sub-base would be adequate. 200mm or 225m would be more usual.

A massive part of the cost is the excavation and cartaway. If you can get rid of all the spoil onsite, you'll save a huge wedge of money, or, if it's a good quality topsoil that's being taken out, then you can actually make a few bob by flogging it off. Sending any surplus spoil to a landfill is horrendously expensive nowadays.

Your next cost is drainage. If your site is free-draining ground, then a simple cambered construction might be enough to deal with any surface water, but, if you're on clay, then you need to allow for a couple of gullies, along with the associated pipework and the essential outfall.

Your sub-base will be more-or-less standard, somewhere around 150-250mm of decent quality granular material. DTp1 is the best, although using a 75mm crusher run might save you a quid or so per tonne. If the ground is squishy or made-up, then a capping layer or a separation membrane could be a wise investment.

And then, finally, you have the surfacing itself. A simple gravel surface dressing can cost as little as 70p per square metre, while a reasonable bitmac, summat like 60/30, would set you back 10-15 quid per square metre, and then an imprinted concrete or blockwork surface would be somewhere around 20-40 quid per square metre, all over and above the excavation/drainage/sub-base and kerbing costs.

The only way to get a realistic costing is to get a few quotes, or to set a budget and see what various surfacing or groundworks companies can come up with.

I don't know any groundworkers in York, although I know that the City Council has cracked down quite hard on the cowboy blacktop gangs that were plaguing the area earlier this year. If you go into a local Builder's Merchant and have a word with them, they are bound to know who, in the area, takes on groundworks of this nature and does a reasonable job. Remember, though, always get at least 3 quotes - don't just go with what the first company tells you.

In Blackburn, limestone chippings are a popular choice because they are sourced relatively locally, at Ingleton or Carnforth, but what you really want is what is known as a 'Self Binding Gravel'. These are relatively fine gravels (not too dissimilar from concreting sands) with a good proportion of "dust" that form a tight, hard surface when compacted.

SBGs vary from region to region and the one that seems to be used most often in North Lancashire (Preston-Blackburn-Lancaster) is the Grano dust from Ingleton. It's usually a bluey-greeny-turquoisey colour with a grain size of around 6mm to dust and is most commonly used for making a granolithic concrtete, but there's no reason why it can't be used as a SBG.

Your local BM should be able to get you a price on a bulk delivery. 1 tonne covers 12-15m² at 35-40mm thickness.

Whereabouts are you?

So, although you might think that a so-called 'nationwide' contractor would be a better option, it's not always the case. I know of at least a dozen cases in the past 12 months where the job has been unsatisfactory, but the contractor has blamed a sub-contractor and then expected the client to have sympathy for them because the subbie won't return. It becomes a legal minefield because the client doesn't have direct contact with the sub-contractor and has to rely on the contractor to mediate, and, as several folk have found, the contractor will usually do what's in their best interest, which may not be the same as what's in the best interest of the client.

If you get a quote from a local contractor, the odds are that it will be them and/or their employees that do the work, and, because they are local, there is more of an incentive to maintain the reputation locally.

Still, when you've got in all your quotes, you should go with the contractor that inspires most confidence, whether they are local or national. It's just that it would be a mistake to think that, just because some company can afford to splash out x thousand quid on an ad in the Sunday paper, that automatically makes them better craftsmen or that they operate with a greater degree of integrity. T'ain't nesser celery so!

I'd be concerned if there was an under-measure. If they are short on the concrete delivery, you know what will happen - it'll be spread thin, or a few bricks and other undesirables will be lobbed in to 'bulk it up'.

Are you sure about these rates and measures? 14k for 14 (ish) square metres - a grand a metre??? I'll haul meself out of me sick bed and do it for 900 quid a metre!  

On such a relatively small job, there are so many other factors to take into account - you're dealing with small or part loads of aggregates, small quantities of edgings and a lot of organising for a job that could be done in less than half a day, all being well. I'd price it as cost of materials plus cost of labour for a full day plus nominal charge for use of compaction plant (say 40 quid) and then put on a decent profit margin of at least 30%.

Small jobs like this are often more trouble than they're worth, so you want to be sure you're getting a good return. If you're at the mercy of the BM to deliver the aggs, then you could find you've a couple of lads sat on their bums all day, reading some scummy tabloid paper and playing cards, waiting for the delivery which only turns up at 4pm.