Now, if you decide to go with the house option, then it's simply a matter of selecting the longest edge as a base line and extrapolating that as required. With an entrance aligned driveway, again the longest edge is used. However, when you have a drive entrance that is not parallel, as you describe, you have a further complication - do you align with the right hand edge, the left-hand edge, the centreline, or perpendicular with the public footpath/roadway?

Without being familiar with your layout, it's not really possible for me to say which would work best for you, but what you could do is sketch a rough layout of the driveway and the house on a sheet of A4 paper and then cut out the outline of the driveway. Lay this sheet over another sheet of A4 on which is printed a herringbone pattern, and rotate until you find an alignment that, to your eye, looks most pleasing. To help you out a bit, I've uploaded a gif file that you can grab and that should print out as an A4 sheet at 1:100.

Having said all that, I still reckon one of the two options mentioned above is likely to turn out best.

Switching to another pattern will not make choice of alignment any easier, as all patterns are based on rectangles, so the same problem crops up whatever you choose. However, as mentioned on the Block paving section, a herringbone pattern gives full pattern interlock, and so is much, much, much better for driveways.

HTH

with a stretcher bond, it will look best laid square to the house thereby striking the threshold with the public highway at an angle. If you do it t'other road round, it looks bloody wierd when you come out of the house, as one of my neighbours who "knows it all" has since discovered.  

And why stretcher bond? A herringbone is best for driveways, as you get a full interlock.

I assumed you were using keyblock or similar, which is best in a herringbone. If you're not happy with the pattern they've laid to date, get them to redo it - you have to live with that paving for a long, long time, and it's easier to lift and put it right at this stage than wait for them to cover the entire driveway, cut it in and compact.

you don't really need any chemical cleaner; in most cases, simply power washing will return the paving to it's best, but, if you have bad staining, a degreaser such as Jizer or plain wash-up liquid will do as good as anything. Acetone is useless, unless you've spilled paint or nail varnish!

Many of the so-called 'paving cleaners' contain weak hydrochloric acid plus a detergent and some perfume. The HCl works by eating away at concrete pavings but has no effect on clays. The detergent is ok and the scent/perfume is a waste of time and money. Be VERY, VERY careful if using these, as they can irreversibly alter the colouring of concrete pavings by reacting the HCl with the Iron Oxide of the concrete dyes. Test on a hidden corner first.

Once the drive is clean and has be re-sanded to fill the joints, have a look at Resiblock 22 as a sealant. It ain't cheap, but it's certainly one of the best paving sealants available. More info on the Sealants page.

1. - it's been developed especially for use on block pavements rather than a 'jack-of-all-trades' product like Water Seal.
2. - it's a SPPU rather than an acrylic
3. - it binds the jointing sand as well as seals the surface.
4. - it has been extensively tested in the most aggressive of conditions, including airport runways.
5. - it should have a lifespan greater than an acrylic, possibly twice as long or more.
6. - it comes in a variety of finishes including gloss, satin or matt, to use paint terminology.
7. - it's used by the trade for the trade, whereas Water Seal et al is more of a DIY solution.

the cobbles you refer to are the rounded beach cobbles, aren't they?

These are often laid in a sand/cement matrix, as illustarted on the Duckstones page, but the grano is a better medium, as it's much harder wearing. However, it needs to be carefully batched when mixing to keep it all the same colour when cured.

Just what the geo-membrane is for, I'm not sure, unless you're on really, really crap ground. The spec I would probably opt for is 100-150mm of C20 concrete with 25-75mm of grano screed bonded to the top and the cobbles set into that.

Has the contractor offered an explanation of why the geo-membrane is necessary?

so, they're a block, are they? Just goes to show what a nightmare paving terminology can be! I must update my library with Armstrongs products.

I'm not familiar with this exact product, so let me check it out before making further comment on the best laying method. However, the comments made about geo-membranes doesn't hold water, to coin a phrase.

Geo-grid can be used to stabilise sub-grades and sub-bases, but it tends to be used on large projects that will be subjected to exceptional stresses, or over 'made-up' ground. If a proper sub-base material is used rather than the rather unspecific "hardcore", there should be no need for a geogrid beneath a residential driveway.

And just how it is supposed to help drainage? I've absolutely no idea. A concrete or other cementitious bedding medium will be more or less impermeable, so what use is a geo-membrane at the interface of the bedding and the sub-base? I wonder if he means a drainage composite?

Anyway, I'll take myself off to Armstrong's website to learn more about what passes for cobbles up there in the north-east.  

I spoke to them on the 'phone and they promise info in the post tomorrow. Mmm. We'll see.

...the next day...

The info, sparse as it is, arrived from Armstrong in this morning's post. The Beamish Cobbles are their attempt at a natural sett-like paving block, similar to the Rialta range from Marshalls or the Ionica from RMC. They are laid in the same way as those two better known ranges, ie, as part of a flexible system, just as described on the block paving page.

Quite why you're being told to use a concrete sub-base, I'm not sure, unless there are problems with bad ground, but the spec I would suggest is for 100-150mm of DTp1, with a 35-50mm bedding course of grit sand and then the Beamish Cobbles, laid hand-tight in courses.

If you have any specific queries about the blocks themseklves, the guy to speak to is Mark at Armstrong's Paving Block division in Consett. Telephone number is 01207 505655 or email . If you have any other questions about the construction method, you're welcome to post back here.

If you go ahead with the work, I'd like to see pictures of the Beamish Cobbles when they're laid.

this sounds ominous - are the edges definitely chipped/spalled?

Most clay pavers have chamfered edges which helps prevent spalling of this nature - are your bricks chamfered or square-edged?

The reason why this happens is that the bricks move slightly when trafficked and by pressing too tightly against their neighbours, the pressure is concentrated on the edges, which then 'spall'. This, I stress, should *not* happen on a properly laid clay brick pavement, which suggests to me that there's summat amiss with your driveway.

The most common reason for this sort of behaviour is that the contractor has either used an inadequte sub-base, or has omitted it completely. The sub-base is the load-bearing layer of the pavement, and it is absolutely essential as it ensures the individual bricks are capable of carrying the weight of cars, vans or foot traffic, without being forced into the ground beneath.

Do you recall a sub-base leyer being laid? It should be a layer of crushed stone at least 100mm thick, on which is laid the bedding sand and then the bricks themselves.

Take a close look at your drive in the daylight tomorrow - are the bricks chamfered or square-edged? Are the joints filled with sand right to the top? Is there any sign of 'ruts' forming where the car runs over the paving everyday? If you can provide me with the answers to these questions, I'll be able to give you more of an idea of what is happening.

I'm not sure what Mill Waste is, as it can mean different things in different parts of the country. Up here in NW England, we call it quarry waste, and it's not always suitable as a sub-base material. With quarry waste, here's no spec governing the proportion of fines to lumps, so you can, theoretically, end up with a load that has no fines or is all fines.

I'm not quite clear on what you mean when you say "Most are 10-15mm across and about 3-5mm deep" - what are? The joints?

It sounds to me as though the sub-base is settling/moving and that is what is causing the bricks to spall. There's no easy solution to this problem, I'm afraid. In some cases, sealing the surface can prevent further movement, but in most cases, the only real fix is to lif the lot, get rid of the rubbish sub-base and start again with genuine DTp1 on a geo-membrane, if necessary.  

all the manufacturers publish brochures/catalogues illustrating their products in the best possible light. use the contact details on the Links pages to get in touch with the various manfs and they'll send you a copy of their brochure in the post.

However, choosing block paving from a catalogue is not the best way - what looks superb when just laid and under special lighting, doesn't look quite the same 3 or 5 years down the line, on a wet Wednesday in November. The best way to choose is to look around and see if you can spot a drive or pavement that you like, and then find out which product(s) have been used.

Hopefully, by the end of this month, I'll have a portfolio of different block types from all the big manfs ready to upload, and you will be able to compare and contrast on this site, but I'm still waiting for one or two of the luddite tendency to confirm their agreement in writing.

What sort of blocks interest you? Plain rectangles? Summat a bit fancy? Olde Worlde? Colourful? Tell us your ideas and I'll see if I can narrow down the choice a bit for you.  

However, if you want to choose a concrete block, there are some intriguing pavers from Charcon incorporating recycled blue or green glass. For a different look, try hunting down the Fanfare or Agora from RMC, or the Penta or Tallis ranges from TopPave.

If it's olde worlde, then Marshalls' Drivesett is a leader, along with Priory from RMC or Antique from TopPave.

Have you got your hands on any brochures, yet?

For colour fastness, you need to choose a clay paver, but these are often slightly more expensive than a concrete. Where you can get a standard 200x100 concrete block for around a tenner per square metre, clays are often start around 12 quid, although there are some 'bargains' out there, if you want to hunt around.

With clays being a 'natural' product that is kiln-fired, they have a more organic, less manufactured look than many concrete pavers, although the cheapest format remains the 2:1 ratio brick shape. Other formats are available, but you're going up the price scale if you move away from the standard format.

Follow some of the links given in the Clay Pavings section of the Links pages and you'll be able to get a few catalogues/brochures that will further bewilder you with choice.  

structurally, there's nowt to choose between yorkstone paving and block paving for a residential driveway, assuming top quality materials are used. A properly laid yorkstone drive will give you at least 25 years of service, as will a properly laid block paved driveway.

Maintenance-wise, they are both similar in that they need cleaning and weeding once a year to keep them in prime condition, although you can minimise this wth the use of a quality sealant.

But cost-wise is another matter. Best quality reclaimed yorkstone will set you back around 35-40 quid per m² just to buy the flags, whereas you can have rectangular block paving completely installed for that sort of price, or a few quid more. New Yorkstone is even more pricey, but there are cheap imports now on the market at around 20-35 quid per m². There is, however, some concern about the quality of the real 'bargain' priced stone, though - see other threads.

Another consideration is that yorkstone is known to 'walk' overnight. Because it has such a good resale value, the drive bandits are always on the lookout for a nice yorkstone driveway that they can load onto their wagon while you're on holiday or away with the caravan. Block paving is much less likely to be stolen.

At the end of the day, it depends on your personal taste, your budget and what sort of property you have. In my opinion, there is no better paving for residential driveways than block paving. It's relatively cheap, it's easily maintained, it's attractive, it's easy to repair. There are indeed some properties where Yorkstone looks better, but for 9 drives out of 10, block paving is a better choice.

I wonder if this contractor is pushing you towards yorkstone because there's more profit in that for them than there is in block paving? Why not get them to price both options and we'll have a look at their specifications, if you wish.

What you are proposing is to lay clay pavers as a rigid pavement to your two strips, and attempt to make it look not too dis-similar to the existing flexible paving. Normally, your methodology would be frowned upon, as rigid paving should really have mortared joints, but, for the scale of the job in hand, I think you might just get away with it.

The outer edges of the two strips need to be bedded on a class 1 mortar (assuming there is not enough depth for a concrete bed) and then haunched as per usual, leaving the inner 'body', which will be pretty narrow. I'd actually be tempted to lay these blocks on clean (ie, no cement) grit sand, but you could use a weak, semi-dry mix if you prefer, say 10:1, with *no added water*. Screed and lay the blocks as for flexible paving, and then compact with the wacker plate.

If you use a wet mortar to bed the blocks, the wacker plate will pump the mortar up and out via the joints, making a right bloody mess of the paving in the process. Using a semi-dry mix, or clean grit sand, and then brushing in jointing sand before compaction will help avoid that happening. The mortar-bedded and properly haunched edge courses will hold the paving in place, so they neeed to be laid at least 48 hours (at this time of year) before the wackering takes place.

Does that help?

the coverage rate for sand is given in the Pop-Up Calculator on the Screeding page, but you should find that, depending on moisture content, it's around 10m² per tonne at 50mm deep

This is one of those jobs that's best decided on a case-by-case basis. Flexible construction is by far the easiest method for DIY'ers, as rigid can be messy and time-consuming, and you have to use clay pavers. So, unless there's good reason, I'd go for flexible.

How feasible would it be to jack-hammer out all the existing concrete?

dolomite is just another rock type and should be fine as a sub-base material. It may actually be classed as a DTp1, depending on its source. Whereabouts are you? Most of the dolomite is found/used in the east and SE.

As for the existing sub-base, after 12 years it's probably settled as much as it is going to settle. A bit of re-grading to the top 25mm or so, and re-compacting should be all that's needed.

It probably is a DTp1. At worst, it would be a DTp2, but it should be fine for your driveway. DTp1 is the stuff they use on public roads - it refers to a distribution of grain sizes and rock hardness, not to a specific rock type. So, f'rinstance, over here in the NW, we get a DTp1 that's gritsone from the Pennines, limestone from the Peak District, hardstone from N.Wales or even a granite shipped into Liverpool from some island they are quarrying of the W coast of Scotland. All very different rock types but all qualifying as a DTp1.

As long as there is the right balance of fines and lumps, it will be ideal.  

With regard to DTp2, it has a slightly different 'grading envelope' to DTp1. I can't find the spec just at the mo', but if memory serves me well, it has more 'dust' than DTp1. It's a minor diff, and not one that would make a masive difference to a residential driveway, but, seeing as it's the same price (to within pennies!) as DTp1, you might as well have the best stuff!

50mm crusher run is a very loose term that would probably be classed as a "Selected Fill Type 1 (SF1)". There's no grading envelope for 50mm C/run - it's all, more or less, passed through a 50mm sieve, so, theoretically, you can end up with all lumps or all fines, but, generally, it's a rough mix of lumps and fines.

Aren't you glad you asked!  

assuming you can get your hands on extra bricks to complete the project, I would take the lot up and re-lay from scratch. You need to lay the pavers with a fall, so that they drain towards a gully or other drainage point, and I'm not too keen on the wide gap between adjacent pavers - they should be laid hand-tight to their neighbours with a gap not exceeding 6mm.

Lift the lot and set aside somewhere out of the way. Re-grade your bedding layer, adding fresh bedding sand if necessary, to create the requisite falls and crossfalls, and then re-lay your pavers. As you're eliminating a gap, you'll probably find yourself short of pavers, which is why I mentioned being able to get hold of extra stocks. If you can't get an exact match, you may be able to use the new bricks to create a soldier edging and then rely on the old bricks to pave the body of the pavement.

Does that help?

the sand has to have some moisture content, usually 3-10%, so it doesn't need to be bone dry before laying. A suitable grit sand will drain itself within an hour of the rain ceasing - if it's retaining water longer than that, then either it's the wrong type of sand or the sub-base isn't draining.

The sand does seal itself, but even so, ants will still mine it, and rain or regular dripping will scour the surface. The only remedy is either to use a quality sealant or to use a joint stabilising liquid, such as the Keybond by Marshalls, or a polymeric jointing sand, such as GeoFix. I've not much faith in either when there's a lot of scour or dripping, so I always recommend a sealant in these situations.

I'm not too sure what you're driving at with your final paragraph. There seems to be half a sentence missing - can you clarify?

As for extending the clay cobbles around the pool, I'd try out the sand joint with sealant - Resiblock will give you a free sample that you can try, enough for you to judge its effectiveness. As I say, try it out, and if that works (it should!!) then you could extend the clay cobbles all around as you originally proposed.

However, if you want other ideas, I'd need to see pics, so I have some idea of what we are dealing with. You can email jpgs to , if you wish.

He was to send me more info, but he never did, and I haven't seen or heard from him since. That's not really the best way to get your products used within the trade.

Does anyone[ have any success stories with Geofix?

it depends on how you define "approved". There is no official 'approved' status for block paving contractors, but some of us in the industry are trying to do something about that.

Anyway, assuming you have a 'standard' driveway laid by a reputable contractor using quality products, it can easily take the weight of a family car, a Tranny van or a caravan.

The strength of a driveway really depends on what the existing ground is like, but, assuming you're on anything half decent, a standard 100mm sub-base with a 35-50mm bedding layer and then a 50 or 60mm block should suffice for a caravan hard-standing

If you have any concerns about the existing ground, you could beef up the sub-base to 150mm and use a geo-membrane between the sub-grade and the sub-base layers.

Good to see you again.

8T may seem a lot at first glance, but here's the calculation in detail.

The density for DTp1 is 1.98 T/m³, so.....

30m² x 100mm = 3 m³ @ 1.98T/m³ = 5.94T

However, the calculation allows for spread around the perimeter of, IIRC, 500mm, so we have 22m of perimeter (5x6m = 5+6+5+6) which gives 11m² extra sub-base....

11m² x 100mm = 1.1 m³ @ 1.98 m²/T = 2.18T

hence, 5.94 + 2.18 = 8.12T

If you reduce or eliminate the spread, you save quite a bit of stone.

I should think it will be fine. If it's been carrying that bitmac drive for 40-odd years, then there's absolutely no point in ripping it out and replacing it with something new. You know it's not going to settle or move - not after all this time!

You may have to re-grade it to accomodate the different levels of the block paving. Most old bitmac drives are 75mm thick, whereas you need around 100mm to accomodate the bedding and the blocks, so scraping off the top 25mm or so and re-compacting is a likely task.

Also, if there are any serious voids in the old sub-base, it's well worth getting in a couple of tonnes or so of extra bedding sand (coarse grit sand), scattering that over the surface and wackering it in to fill any holes before placing the bedding layer.

Hope it goes well for you - keep us informed of how you're doing.

sounds like a job that could use either a short length of land drain beneath the sub base or a drainage composite. I'd definitely consider using a geo-membrane, something like Terram 1000, as that will keep the sub-base separate from all that clay.

Skim off any sloppy clay/mud on the surface, get the geo-membrane down and the sub-base in as fast as poss before the rain returns. Once it's in and compacted, it will help prevent the sub-grade degrading any further and you should have no further trouble - touch chipboard!

Why 60mm of sand? Is that before you compact and screed it?

This is how I'd do it....

Establish centre, then set kerbs on semi-dry mix at 1.3m radius (2600mm dia) and place haunching concrete to back, but don't compact solid.

Screed bedding layer for circle, allowing for fall from centre to edges (25mm is about right), then lay the circle starting with the centre stone monstrosity and work your way out. When you get to last ring of blocks, bed them on extra haunching concrete and push up the kerbs to suit, so that the backs of the kerbs are tight against the edge of the blocks, which should be approx 3mm higher.

Use a rubber mallet to knock down the outer ring blocks to the correct level, which will compact the haunching concrete at the same time, and then, when everything's in place, haunch the front of the kerbs to prevent them being kicked out, or lay more blocks.

Leave it for a couple of days before wackering, to give the concrete a chance to set.

yes - you still need a sub-base and a bedding layer, even though it's only a patio. If you have really firm and stable ground, you could get away with 75mm of sub-base, but any less than that isn't really a sub-base: it's just a fill layer, with no inherent strength.

The strength of a sub-base comes from having a minimum thickness, 75-100mm, of a certain mixture of stone and fines. It is the load bearing layer of the block pavement and it's a false economy to skimp. The biggest single cause of sunken paving is inadequate or missing sub-base.

You don't need a geo-membrane. They're handy on bad ground, but for a lightweight application such as this, they are, as you say, overkill.

And as for the bedding layer, you need enough to 'cushion' the blocks, enough to allow them to bed in, but not too much so that there's a risk of settlement. The minimum recommended thickness is 35mm, but that relies on your sub-base being accurate to not more than +/- 10mm.

It's not worth spoiling the ship for a ha'porth of tar. It's a lot easier to do a bit of extra digging, and use a few barrows of extra sub-base at this stage than face having to lift and relay next spring.

You don't absolutely need concrete under the blocks adjacent to the house. We do it that way so that, when we screed off using those blocks as a level guide, they won't be dislodged. The house wall will act as the restraining edge.

For your kerbs, though, they must be on concrete and haunched with same. If you're draining towards the kerb and hoping to allow surface water to find it's way through onto the garden, you may need to leave an open joint in the kerb line every 500mm or so.

How's that?