Send me a picture and I'll add it to the DIY Drives page.

Could the whole area of paving be surrounded by concrete (as the 3x2s are at the moment) to prevent movement?

The perimeter of a clay brick (or concrete block driveway should always be laid on and haunched with concrete. There are exceptions, but they are few and far between.

In your situation, I would insist on a firmly bedded and haunched edging course, particularly at the bottom and the sides.

I am concerned that due to the slope and poor drainage the water might drain 'down the hill' and over the blocks rather than between the blocks thus making the moss problem worse. Is this likely?

It's more than likely; it's absolutely certain!

Despite what seems to be a common misconception amongst members of the public, surface water does NOT drain through the joints of block paving. There's a study been done by the TRL (IIRC) and they calculate that 98% of the water that lands on a flexible block pavement will run-off - only 2% finds its way via the joints to the laying course and sub-base. Surface water does NOT drain through a block pavement. Some provision for collection and disposal of the SW must be made - gullies, linear drains and/or channels will be needed.

However, as you correctly state, clay pavers can be particularly prone to mosses, more so than concrete pavers, and not just the joints, but the surface of the pavers itself. Now, given the very steep nature of your driveway, this will be countered to some extent by the water cascading over the pavement during the  wet weather. Once the slope of a block/brick paved driveway gets above about 1:10, a sort of self-cleansing property becomes apparent, and mosses, algae and other vegetation find it hard to survive. That's not to say they find it impossible, just harder than it would be on, say, a 1:60 driveway.

This is easily remedied, though. Use of a quality urethane-based sealant will counter colonisation by mosses and other weeds, and, more importantly on your steep drive, will prevent the essential jointing sand being scoured out by the run off.

My opinion is that you should have no qualms about using clay pavers for your driveway. Laid properly, they will outlast us all, but I can't recommend too strongly the use of a quality, tested-and-approved sealant, not just to maintain its good looks, but to ensure its longer-term structural integrity.

One last point - you may want to consider using rigid construction for your driveway, rather than flexible. I can't say which is more appropriate without being familiar with the site, but it's certainly worth interrogating your contractors when you get them round to price up the job. A steep driveway in clays is a prime candidate for rigid work.

In fact, you could probably get away with a 1m radius, giving you 3 full fans to one width of the patio, excluding the border edging. I have a drawing somewhere - give me a couple of hours to finish what I'm supposed to be doing and I'll see if I can find it and post it to this thread.

I have used a fan pattern with the clay cobbles on a number of occasions and they have to be the easiest paving unit to use with what is normally a complex pattern. You will need to split a few cobbles, but they are easily and accurately cracked with a lump hammer and bolster, and, because they have a raggedy-rusticky jagged edge anyway, you don't need to be exact.

For the border, I'd strongly recommend using a 200x100 clay paver. It forms a definite frame, rather than a bitty border, especially if a contrasting colour is used. There are some pix on the portfolio page that show the cobbles with a full-sized clay pavior as a border/soldier edging.

More later....

Images as promised....

This first one is a layout for a 560mm radius layout....

...while this second image is for a larger 870mm radius fan, which would give you 3 full fans across the patio, assuming a 200mm wide soldier course at the perimeter.

Any help?

I'd definitely use the larger fan. The 560mm radius will look too small and will lose itself. The fans need to be large enough to impress upon the eye, but not so big that you have to stand at the top of the next street to understand the layout. The ideal fan size for a patio project is usually between 900mm and 1500mm radius.

The teg cobbles are quite subtle and don't look as natural as clay cobbles, but then, they don't get colonised by mosses quite as quickly as do the clays.

I'd make my choice depending on the look I was trying to achieve - rustic and lived in, definitely the clays: clean, up-to-date but traditional, the Teg Cobbles. Cost wise, I don't think there's more than coppers difference between the two.

Have you seen either of these products "in real life" or have you only seen publicity shots in the catalogues?

If you contact Baggeridge they'll tell you where you can see the cobbles 'in situ'. They keep a list of projects where their products have been used. Try to view a job that's at least 12 months old, preferably 2 years or more, as the character 'mellows' with time as dust and detritus become ingrained and make the units look much more 'lived-in', IYKWIM.

It's worth asking a local paving contractor for a price, as I know a client that has bought them for less than 30 quid per m² in the last 12 months. They might be able to get you a keener price by adding whatever you need to a local order.

That was for delivery to Sheffield (from Accrington, where they are made) and was for 112m², IIRC. I'm pretty sure they were bought through a local BM not[ one of the nationals such as TP or Builder Center(sic)

I'll see if I can get hold of the contractor tomorrow and find out just who they went through, if you'll pardon the expression.

However, 1 Tonne of bedding sand won't be enough for 15m². You need nearer 1.5 tonnes, again depending on moisture content, which means buying 2 agg bags full. Given that you are tight with the sub-base material, you really can't afford to run short of bedding. Get 2 T of sand - the surplus can always be used for making haunching concrete or even added to the garden to improve a clay soil.

Congratulations on such a great job!

Firstly, it's possible to create a random layout in such a narrow space, if you choose the right flags. I could do you a custom design, for a nominal fee -

Alternatively, you are best using a CAD system, drawing the components to scale, and then playing about with them in a scaled drawing of the patio/path area. much as described on the Random Layouts page.

If your budget will stretch to it, have a look at Marshalls Chancery range. They are much more authentic looking, compared to their Heritage paving. Or you might like the Millstone from Stonemarket or even the Old Town from Bradstone.
Further, given you've such a tight area, I'd have a look at using something like the Tegula block pavings. Because they are relatively small units, they have the effect of making small spaces look bigger than they actually are, and a transverse (running across) pattern would prevent it all looking terribly narrow.

There's not much of a price difference between high-quality patio flags and tumbled blocks when used on an area such as this, and the Tegs are much easier for a DIY'er to lay.

Secondly, your damp problem. If you are re-paving the likely leak area, it's worth pricing up a drainage composite, such as Terram 1BZ, which can be laid horizontally, beneath the new paving to prevent any surface water finding its way through the paving and into your cellar. However, you may well find that it's groundwater from elsewhere that's penetrating the walls, and so a vertical drainage composite or impermemable membrane might be a better option.

Have you done any trial holes?

If you contact Marshalls, they'll tell you where you can see it locally in situ, as it were, which is a much better way to choose.

For a fan pattern, you really need a minimum area of approx 5m x 3m. Anything less looks unfinished, unless you use under-sized fans, and then the whole job looks bitty. The trick with small spaces is not to try and dop too much. Keep it simple and it makes the space look bigger than it actually is.

Trial holes - basically, as small a hole as you can manage going down tight against the wall(s) with the damp problem. You're looking for owt obvious, like crumbling or rotten brickwork, open joints, fissures or cracks etc, or any standing water. It's one of those tasks that is best judged by someone with lots of experience, I'm afraid, but you might see something. At least it costs nowt!

with regard to the damp, is there any chance it could be the drain you mention that is leaking? If you add a drain-tracing dye to whatever empties into that drain, it would show up in the ground water if there was a problem with the pipework, such as a leaky collar, or a cracked pipe.

Tracing the old dpc company - they are/were notorious for allegedly going bust shortly after making a huge wedge of money, much like some of the PIC Contractors we have nowadays. Companies House is your best bet in tracking them down.

If the drain is definitely above suspicion, then it might be worth getting a "no-obligation" damp survey done and see if that turns up anything.

I'm sure you'll enjoy the Tegula - let me know how it goes.

The gravel strip is, to my mind, a cheap cop out and again, I wouldn't be happy with it. You're paying for block paving, not bloody gravel!

I'm not familiar with the layout at your property, but the correct procedure when there's insufficient fall to drain an area of paving is to create a low point and add an extra gully, NOT elevate the paving up towards the dpc. How feasible this would be on your project, I can't say.

At the end of the day, it's your paving and you have to live with it. If you're happy, then fair enough, but, you must bear in mind that any encroachment of the '150mm below dpc' standard is the sort of thing a surveyor picks up on if you come to sell the property and then you're left with the choice of reducing your asking price or paying for remedial work.

My question to them would be why they haven't created a low point and installed an extra gully. This should have been allowed for in their original survey and pricing of the work.

Maybe someone else reading this forum will be able to suggest a good contractor. Is it North London where you live, or are you south of that little stream that runs through the middle of the village?

As for light coloured flags - depends what you're looking for. Something simple? Summat textured? Olde Worlde riven? Funky and contemporary? There are so many to choose from - I started building a 'gallery' of all the different types of blocks and patio flags about 6 weeks ago and it's still nowhere near finished!

Best suggestion is to get yourself a few catalogues. The Marshalls and Bradstone offerings are essential reading (although the Marshalls 2002 is so arty-farty, it's hard to judge the actual paving!) as they cover the widest ranges, but there's some really good products from companies such as Stonemarket, Bowland, Atlas, Charcon etc.

Tell me more about how you envisage the patio, and I'll see if I can suggest a few 'candidates'.

Set up a back sight at, say 1200mm above dpc on the corner of the house, then position a 1200mm fore sight on the public footpath, propped up with bricks or fixed to a footplate. Then, using a traveller set to (1200+100=1300mm) you can check the level of the top of the sub-base by sighting through, positioning the traveller anywhere you like between fore- and back sights.

You can repeat this for the back section, setting a fore sight at the garden and a back sight at the house.

If you want to form a hog-back curve in the profile, then have a look at the Profiling Kerblines[ page for further guidance.

Once the sub-base in laid, I prefer to lay my edging courses next, on a cement-bound bed and then use them as screed guides for the rest of the paving. That way. I can play about tweaking the profiling to achieve the sweet curves I prefer, and if necssary, the sub-base can then be checked again by stretching a string line from edging to edging course and 'dipping' to check, adding or taking away from the sub-base as required. Remember, a sub-base can be +/-10mm, but the more accurate you are, the less likely is the incidence of differential settlement in later years.

If you're not familiar with these terms, just let me know. I'm guessing you're a Contractor and will be familiar with boning rods, diff. settlement  and hog curves, but if it's all Greek to you, post back and I'll explain it all in Layman's terms.

To put that in layman's terms, the smaller bits in the sub-base may settle by, say, 10%, but the big lumps will not settle, or will settle only, say, 3%, so that what was a level sub-base soon becomes an uneven sub-base, and this difference in settlement is carried through to your paving, turning a level pavement into an uneven surface.

If you're intent on using the old concrete as a fill/sub-base, it's really worth the extra effort of breaking it up properly, with a sledgehammer, if necessary and getting a good, even sub-base. The analogy I always use is that of an underlay beneath a carpet - it doesn't matter how much you spend on the carpet and how well it is laid, if the underlay is crap, the final carpetting will be crap too.

40 m² would certainly be more appealling to a Contractor than 16m², but it's still on the small side. Were you looking for a Contractor?

Eurobright Construction Ltd.
36 Gresham Road, Custom House, LONDON. E16 3DU
Tel: 020 7473 5491
Fax: 020 7473 5491

MJB Contracts Ltd.
Sinclair House, The Avenue, West Ealing, LONDON. W13 8NT
Tel: 020 8842 0043
Fax: 020 8842 0043

Tarmac Situsec
40-45 Herringham Road, Charlton, LONDON. SE7 8SJ
Tel: 020 8858 9409
Fax: 020 8305 2002

....or you could try the Marshalls' Register on their website - type in your postcode and it will give you a listing of your nearest Marshalls' approved contractors.

You should still get at least 2 quotes, just to be sure you're getting a fair price for your area.

Let me know how you get on.

As for the kitchen step, I'm not with you. If you elevate the level of the patio by laying Classico Paving over the ex concrete, how will this impinge upon the kitchen step? If you have, say, a 150mm step from ex patio to kitchen threshold, then by laying the pavers over the ex patio, that would elevate the paving level by approx 90mm, reducing the step height to 60mm (more of a trip than a step), but there's no need to start fiddling with doors, as far as I can see!  

There's been a lot of new developments in treshold drains to aid compliance with Part M of the Building Regs for disabled access,. RMC have a channel called 'ReadyStep', IIRC and Hepworth have a slot drain that can be used. These help create a safe flood barrier at doorways where the internal floor level is flush with, or only slightly higher than, the external paving level.

They're worth taking a look at - your local BM should have one or more sytems in stock, and they're all under 30 quid, or thereabouts.

I'll dig out more info, if you need it, but your BM should have the tech literature and all the fancy pictures you need.

However, there are also a lot of imports coming in from India, China, South America and also from Southern Europe. Some of these may well be quality products, manufactured from a suitable local stone by dirt cheap labour then shipped over here and sold at a price slightly below that of UK-original materials, but a lot of what I have seen has been of dubious quality. Flakey, crumbly or overly laminated and aimed at the unsuspecting Garden Centre market rather than the more knowledgeable Builders' Merchants.

As most of the imported material does not carry any agrement certificates or verifiable BS or even ASTM compliance, you have to be very wary about what you buy and who you buy from. BMs are usually very careful when it comes to their suppliers, and most of the specialist stone merchants will give an honest opinion on their stock, but the GCs will sell whatever they think the general public will like the look of, regardless of long-term quality.

From your description, I suspect these are the genuine yorkstone setts. Have a look at Farrar's website as they offer a nice range of widths and lengths.

Can you get a picture, Richard?

I answered this in my reply to your email, yesterday (Saturday)

This information is given on the Sub-base page and on the Screeding page.

I wouldn't seal a driveway so soon after laying. I'd leave it until the back end of the summer, give the jointing sand time to settle and bed in properly and to ensure I'm not sealing in effloresence, which is a common feature of concrete (not bloody cement!!!) pavers.

look at the Repair and Maintenance page for guidance on how to lift and relay the sunken paving. You can re-consolidate using a rubber "clonker" (see Tools page) or even by hammering a timber board laid over the replaced paving.

Don't forget the jointing sand - it's absolutely essential!

Weedkiller - we normally use Sodium Chlorate, but Pathclear or Tumbleweed is fine.

Is there some reason why the joints are wider at the threshold of your driveway? They should all be the same size, really - around 3mm.

Anyway, there's a couple of ways to keep the jointing sand in place. The simplest is to use a "Joint Stabilising Fluid", such as Keybond by Marshalls. This is, basically, a PVA glue that is diluted with clean water and allowed to soak into the joints whereupon it sets and binds the sand grains together.

The other option is to use a paving sealant (see Sealants page). This does more or less the same job of binding the sand grains together, but also creates a seal over the entire pavement.

Whereas the keybond-type products seal only the joints and have no discernable affect on the appearance of the paving itself, the acrylic or urethane sealants give the blockwork a sort of 'varnished' appearance that, to be honest, isn't to everone's taste.

From personal experience, the urethane sealants do the best job, but, if you don't want the semi-glossy look, try the keybond and see how it fares over the first season. We find that, for the best protection, the Joint Stabilising Fluids need re-applying every couple of years, but they are only a fraction of the cost of a quality acrylic/urethane sealant.

It should be noted that with clay pavers, the 'varnishing' effect of sealants is far less noticeable than it is with concrete blocks and, because the joint widths are so variable (6-10mm wide in extreme circs), it's well worth considering the use of a decent Sealant on this type of paving.

HTH

Take up a few of the blocks (see Maintenenace and Repair page) and check the bedding/sub-base before relaying the blocks to the correct level. Once you've got the blocks back to the correct level,and the joints re-sanded, then you can apply the Keybond.

there's no effective way to eliminate the ruts (known as channellisation) without removing the blocks. I'd suggest lifting up an area at least one block wider than the affected area, and taking a look at the sub-base layer. You may need to consider scraping out the bedding sand and topping-up the sub-base rather than keep adding sand.

If the sub-base itself is badly affected, it might be worth lifting the lot and putting in a separation membrane (see Geo-Membranes page) beneath the sub-base, relaying the sub-base, the bedding and then the blocks - not the sort of job you can do in an hour or two, I know, but probably more effective in the long term.

Anyway, assuming the sub-base is reasonable, and doesn't need to be excavated - add more sand to the bedding layer, lightly compact it with the plate compactor and then screed it out to level. Replace the blocks, brush in the jointing sand, compact the lot with the plate, and then treat yourself to a well-earned pint.

Try and find genuine jointing sand rather than using the same stuff that's used for bedding. The grain size really is critical to generating sufficient friction between adjacent blocks to help them carry the load. If, as you hint, they've previously been jointed with any old sand, then that won't be helping matters.

If the channellisation keeps re-appearing, it suggests the sub-base is inadequate and may need to be replaced to below the frost limit, which will be what is known over here as a right bloody ball-acher!

Have you had a sealant applied to the blocks at all, Jerry? That can help reduce some channellisation, but I've not much experience of frost heave damage, so I can't swear it would be a definite help.

You only lay block paving once - might as well get it right.

How old is the property?

From what you tell me, I would work on a max paving level of 150mm below internal floor level, ie, 2 courses below the eng bwk. If you wanted to go lower than that, it wouldn't be a problem, but most properties built since the mid 1930s rely on a minimum level diff of 6" (150mm) between internal floor level and external ground level.

How does that fit in with your plans?

Secondly, a sub-base helps ensure a regular thickness of laying course material can be used. which, in turn, helps avoid what is known as differential settlement. It  also eliminates any deviations in the level or 'hardness' (CBR) of the sub-grade, creating a suitable and solid surface for the actual paving.

Thirdly, most block paving is subjected to vehicular traffic and so a sub-base is essential otherwise the paving would just 'rut'.

While the 3rd reason doesn't apply to patios, the first two reasons apply to ALL block pavements, even simple patios or paths. Obviously, on your own property, you could choose to disregard this advice, but then your paving will settle over time and end up looking a right bloody mess!