The standard colour, a sort of buff, will be fine, as the joints should only be 5mm wide and, in 3 or 4 months time, the surface will have discoloured and become covered in detritus, so you'd have no idea which colour (from the vast choice of 2) was used originally.

Patchy dark/light areas? That doesn't sound right - do you have a photo or a fuller description?

I'd leave it for this summer, then look at it again next spring, when, hopefully, all the eff. will be long gone.  

There are no readily available "similar products" on the British market. Marshalls have their Stein & Design imports from Germany, but these are really aimed at commercial works rather than patios, which is reflected in the cost. No British manufacturer has a washed aggregate block paver, currently.

There are other textured pavers, such as bush-hammered or shot-blasted, but these textures should not be compared directly with a washed aggregate, as they still rely on the artificial dyes in the concrete matrix for their colouring, unlike the Washed Aggs. which derive the vast majority, if not all, of their colouring from the aggregate which is exposed by the washing process.

The Charcon Moordale is, if I recall correctly, a shot-blasted product, and so the surface exposes both the concrete matrix and a small proportion of natural aggregate. As far as I know, the texturing is only carried out to the top face, so the sides/edges of the flags would not be similarly textured, which may not be what you're looking for.

3 - compaction with a vibrating plate can't do any harm, but I'm not sure it would do any good if it's simply a matter of running the vib plate over old mortar.

4 - You could re-lay on fresh bedding over the old mortar bed, as long as there is no problem with DPC and levels, but see (6)

5 - There's no need for a bedding mix to have such a high cement content. 10:1 is fine - see the Laying Flags page for info on my preferred bedding mix.

6 - A sub-base is not essential beneath a residential patio, but can be used if there is a problem with bad ground or with levels that required lifting.

If this were my job, I'd actually rip out the old mortar bedding and either bin it or break it up to pieces of 50mm or less and sprread it out over the whole site as what we call a 'blinding' layer. Then, if there is a need for a sub-base, lay that, compact it with the vib plate, and then re-lay the new patio, on my 10:1 semi-dry bedding mix. I would not be 100% happy laying parts of the new patio on top of old mortar (a rigid base) and part of it on a flexible sub-base, as the two parts would behave differently over time and you could end up with the dreaded differential settlement.

How's that?

2 - probably not. Old mortar, even a 5:1 mix isn't terribly hard stuff and breaks up with a few thwacks from a pick and/or a sledgehammer.

3 - For a patio, you can use whatever is easiest to get hold of. That might be DTp1 from a local BM or "Crusher Run" from one of the DIY sheds, or cruushed concrete, 'ballast', 'scalpings' or whatever else is on offer. As long as its a good mix of fines and lumps, and compacts well with the vib plate, it'll do for a patio.

For driveways, I don't believe in spoiling the ship for a ha'p'orth of tar, and always recommend genuine DTp1, but for patios, almost any crushed aggregate will do.

Let us know how you get on, and take photies as you go. The feedback I get tells me that folk love gawping at other folks' DIY efforts!  

2 - the mystery gap between the house and the paving sounds like a bit of laziness. Maybe they couldn't be bothered cutting flags to fit, or maybe they couldn't be bothered knocking up a bit of grano to infill the gap, but you can safely pave right up to the house when you come to do the work.

Good luck!

We found it worked best with wider joints, especially on setts/cubes, but that is was less successful when it came to curing 'rocking' flags as it didn't sem to penetrate beneath the flags and fill the gap/void in the bedding. Also, on some paths laid on spot bedding (not laid by us, I hasten to add!!) the ability of the paving to swallow huge volumes of the foam was frightening.

We were obliged by the property owner to effect 'permanent' repairs as soon as practically possible, although some of the smaller repairs could have been left as they were. However, with some sett work that had been patch-repaired with foam, visitors to the nursing home in question were complaining that ladies' heels were penetrating the foam and getting stuck, hence the requirement to replace the foam with a solid joint medium asap.

I also seem to recall that it was less successful on pavements that were subject to vehicular traffic, even though it was only low speed "car park" traffic. Several of the sett rumble strips we repaired in this way worked themselves loose again in just a matter of days.

I'll dig out the job records later and see if I made any other notes regarding the efficacy or otherwise of the foam repairs.

HTH

taking your queries one at a time....

"What depth of base would be best?"

The bedding should not be more than 50mm deep, but, if you want to lay a sub-base (not essential beneath a patio, but useful on suspect ground or when levels have to be elevated) then a minimum of 75mm is the usual recommendation. 100mm is ideal.

"120 x 60 flags - is this size too awkward to handle?"

It can be if you're not used to flagging, but, by including a few of them, you increase the random appearance of the stone. I'd also consider splitting a few of the 600x600 squares into two 600x300 rectangles for the same reason. If you rely on just two sizes (600x600 and 600x900) the paving becomes very repetitive and doesn't show off the natiural variation of the stone as well as it could.

And I'm definitely interested in photos - send them as email attachments or post them directly to this forum.

when it comes to flags, you gets what you pays for. The Salisbury range are a "Budget" version of Marshalls' Heritage or Bradstone Old Riven and you have to ask where the cost savings are made - by using poorer dyes, less of them, and a lower cement content. You might save a fiver per square metre, but, in 2 or 3 years time, they start to look like what they are - concrete copies. Many folk are now switching to the imported sandstone flags - they cost a few quid more, admittedly, but they are genuine stone and can't end up looking like poor concrete copies a few years down the line.

However, as I always say, it's you that has to live with these flags, not me, so you must choose what you like, not what I like!

For a random pattern, you might find that the manufacturer offers a basic random layout that you can adapt, or you might be able to use the misleadingly named Random Patio Generator from Bradstone, or you can work out a pattern for yourself, as described on the Random Layouts page. If you have an irregularly shaped area, a custom-designed layout is your best option.

And finally, for your ugly MH covers - replace them, with Recess Tray covers, as described in the block paving section of the website. Regardless of what size are the existing covers, there is a tray available to replace them and make them damn near 'invisible'.  

To buy a tray to fit your MH exactly would cost around 600 quid and would have to be specially manufactured, whereas you can get a reducing slab for 20 quid or thereabouts, and a standard tray for under 40 quid. The reducing slab is simply bedded onto the existing brickwork and the tray sits on top of it - it's an absolute doddle! That is how a 'professional' would do the job, Grahame.

If you have no luck at Parrs/Builder Centre, there's Burdens here in Sunny Warrington, or Cooper Clarke in Bolton, both of whom definitely have the cover slabs available ex-stock.

I thought you might have been able to get away with a 1200x750 rectangular cover slab, which are easily handled by a couple of fit lads (or lasses!), but the internal dimension of the chamber width is 727mm, which means there's only be 23mm (less than an inch in old money) of spead onto the side walls.

This leaves you two options - you either corbel in the top course of brickwork so that the 1200x750 reducing slab is properly supported, or you use a 1350mm dia circular 'biscuit', which is considerably heavier than a 1200x750 reducing slab - 400kg against 80kg - and would have to be craned into position....

...I think, if this is a DIY effort, the corbelling option is the simpler for you, but, if you're bringing in a contractor, then the circular biscuit might be their preferred option.

Does that make any sense?

Have a read of the main site, where all this is explained in great detail.

The retainer can be brick, or an edging kerb, a flag-on-edge, a timber edging or old setts or anything you want - you only have 300mm of lift so you're spoiled for choice. If you want to use bricks, I would use 225mm engineering brickwork on a 450x100 concrete foundation at a depth of not less than 150mm, but, fo only 300mm of lift, that seems like a lot of work to me.

For the fill, you should only use inert material, so no soil. DTp1 is the best material, but you could use gravel, all-in ballast, crusher run or lean mix concrete if you preferred.

You need to come up with a plan for this patio before you start work. All the questions you might have are answered on the main site, but it involves you making decisions on what you want it all to look like once it's finished, how confident you are with your own skills, and how much you're prepared to spend. I can't take these decisions on your behalf.

There's no specialist supplier of reclaimed concrete flags as they are generally considered to be worthless. Your best bet is a local reclamation yard that might just have a few, or look around at your neigbours, especially if anyone is having a new driveway or patio, as their flags are probably the same and would be dumped if not salvaged. The lads laying the new paving will often let you have the old flags for a quid a piece, delivered, as they cost a small fortune to get rid of in a skip.

You have to bear in mind that, in the 1950s, there were literally hundreds of small, local manufacturers for flags, because no-one wanted to haul the damned thing a hundred miles or so, as they do nowadays. When you get to be as obsessed with paving as I've become, you start to notice the different aggregates that were used in certain towns. St. Helens, for instance, had a flag making factory at Sutton Junction, just half a mile from the old Bold Colliery/Power station complex, and their flags incorporated a lot of cinder and ash, giving them a distinctive look that can still be seen on the older flagged paths in St. Helens, Warrington, Wigan and parts of Liverpool.

It's highly likely that your flags came from Crewe or Stafford and the aggregate may well be unique to your area, so you have to hunt around locally. Do you have any photos? If you do, I might be able to identify the type you have and let you know where I've seen similar.

In theory, the Slab-fix would 'set' (I think 'stiffen' would be a more accurate term) by drawing moisture from the air and the ground, but you've been unfortunate in that we have just been through a very dry and warm spell, and, because you used a sub-base, there is little, if any, moisture in direct contact with the bedding product.

However, as you sprayed the area with water, it really should have 'stiffened' by now, which leads me to wonder whether this is a perished product, ie, one that's been left on a shelf for too long so that the lime content has hydrated before you opened the pack.

I think this stuff is an expensive bedding and a way of extracting yet more money from non-trade folk who don't realise just how simple and cheap it is to knock-up bedding mix for themselves. I would not buy any more Slab-fix, but would switch to a tried and tested bedding material, namely sharp sand and a dash of cement, such as the 10:1 mix I advocate.

As for the pointing, use a Class II mortar, as described on the main site, or take a look at the pages that deal with the art of pointing for a fully detailed guide to what works and what doesn't.

Assuming it's all going to be new, I'd lay the extended area on my usual patio bedding mix (semi-dry, 10:1, sharp sand with cement, no added water) and lay over the old concrete base (assuming the old flags can be separated from the concrete) using a thin full bed of a Class IV mortar.

There's no need to cast a concrete slab beneath the patio just to match the one course of paving that's already present, unless you have really bad ground.

Good luck!  

We in Britain and Ireland are lucky in that we don't get any frost heave worth mentioning, otherwise the national rail network would use it as yet another excuse for not running any trains. Consequently, I don't have much experience of pavement design in continental climates, but, from what my colleagues tell me, a flexible construction (sand only) is expected to move, but a rigid construction (cement-bound) has to be of sufficient thickness to withstand significant heave, which can be as much as 600mm, I'm told. So, the short answer is that, if you want a non-moving patio, you need to use concrete as a bed.  

These products work by 'glueing' together the sand grains, preventing them being blown or washed out.

Their website is at www.envirobond.com and I'd be glad to hear how you get on.  

The first thing I'd say is that joints between your slate pieces are awfully wide. When constructing what we call Crazy paving, the trick is to keep the joints to a minimum width, filling in wider joints with additional stone pieces as required. I've nicked one of your images, shrunk it, compressed it and reproduce it here for the benefit of other readers....

Where wide joints like these are unavoidable, they're normally filled with concrete/mortar, and then topped with a surface dressing or gravel or grit, so that it doesn't look like concrete but has its strength and prevent the jointing being scuffed or kicked about everywhere. If this were mine, I'd seriously consider using an Exposed Aggregate finish concrete in the joints, because I know I could make it look really good.

Here's an image of crazy paving from a derelict garden I frequent on the outskirts of Bolton, Lancashire.....

...notice how 'tight' are the joints, compared to your project.

The joints are the weakness in a pavement such as this, so, by keeping them to a minimum, you maximise the strength and longevity of the paving. The example above was paved around 1906 and has never been relaid!

BRW - nice garden - You can take a peek at my garden and see how it contrasts with the gardens in your part of the world.  

Pros - unlikely to move

Cons - expensive, unforgiving if you don't get it right first time, and limited working time.

You have to find a balance between adequate fall for drainage, without it feeling/looking odd, and without the patio table inducing a feeling of sea-sickness. At the end of the day, the choice is yours - if you instruct the contractor to lay at, say, 1:70 (15mm per metre), then you can't complain if you get small, short-lived puddles after a downpour. Personally, I wouldn't be too worried about 1:70   :)

The usual spec is to re-cover the roof with a particular membrane or tanking, then the Caro-Supports, and then the lightweight flags, which are sometimes known as Promenade Pavers (complicated, because Baggeridge Brick make a range of clay pavers sold under the name 'Promenade').

I've only ever been involved in this type of job once, and the roof had to be demonstrably strong enough to carry the weight of the paving plus the additional imposed loads. This 'proof' is done by a structural engineer - just laying flags to your flat roof quite probably invalidates your Bricks'n'Mortar insurance!

I'm not sure how suitable a job it is for DIY. From what I recall, and I'm going back about 8 years or so, it was ridiculously expensive work. The membrane/tanking cost a small fortune, and it took us twice as long as anticipated, but, to date, there's been no comebacks (Thank God!!)

it's good to see someone else validating my crusade to rid the world of the evil that is known as "Spot Bedding" for truly it is an abomination that must be eradicated and its proponents slung into the pit of despair!

The 10:1 bedding mix should be more than capable of dealing with you patio and the heavier-than-normal surface water regime. The purpose of the cement is to bind the aggregates, rather than make it hard-wearing or incredibly strong. As long as the cement content is adequate to hold together the aggregate particles, it will be fine, and, in my experience, 10:1 is about right. You can elect to make up the "10" from 5 parts gravel and 5 parts sharp sand, if you wish, or you can 'edge-your-bets and up the cement content to a 8:1 mix, but these are minor details that I leave to your choice.

Screeding is possible if you're using regular thickness flags or block pavers, but, if you're using the riven types, other wet-cast products or natural stone paving, individual bedding is the best method to employ. Keep the bedding to a maximum of 50mm, and no more. 35-50mm is the standard specification.

Good luck and let us know how you get on.

I've never used lead pointing in over 30 years of laying flags, and the only time I've ever seen it is on a certain ecclesiastical property in the north-east of England, which I won't name for fear of it being visited by the lead goblins when darkness falls.

Where have you seen it, Danny? Send the answer by email or use the confidential Messenger system above, if you prefer. I wonder if we're both talking about the same place?

Personally, I can't see any advantage to lead jointing of paving. It doesn't form a watertight joint, as you'd get with a mortar or with pitch; it goes dull with time, so no-one can tell it's lead unless they look very carefully, and you can achieve a similar effect using a dusting of lead, tin or solder on top of a 'proper' mortar joint.

If you must, though, then all I can advise is that you get yourself kitted up with a mask, long gloves, decent boots and use a long-handled pitch-pot over a gas ring, which you can get from any decent Hire Shop. I'm not sure what grade of lead you should use - perhaps a plumbing specialist could advise, or you might be able to get more info from British Lead Mills (BLM).

I'd be interested to hear how it goes, and, if you do lead your joints, I'd love to see pictures!