You could also use steel road pins, which are sold via most Builder's Merchants for around a quid each.

When backfilling, do it in layers not more than 200mm deep. Compact each layer before moving on to the next, and work your way to the top in a succession of such compacted layers.

Anyway, surround the exposed service pipe with sand, cover it with marker tape, if you have any, and backfill the trench with DTp1 or other suitable sub-base material in layers not exceeding 200-225mm in thickness, compacting each layer as you proceed.

When it comes to the paving, make sure it's at least 150mm below dpc and follow the tips I gave previously on backfilling in layers.  

It must be 20 years since we last did any rabbit-fencing, but I don't think they've learnt to dig deeper or jump higher in that time.  

A typical fence post has 1.8m above ground and 450mm buried, which is only one-quarter.

Contact your local Building Control Office (BCO) and ask them to recommend a local draughtsman/engineer/architect who will flog you an 'off-the-shelf' plan for your area. As a rough guide, most rafts are less than 1.5m deep and I wouldn't expect a raft for a single storey garage to be any deeper than that.

However, from what you say, I think you might be ok using your on-site hoggin as a capping layer, to elevate levels, and then see how it goes. If, in a year or so, when you're ready to install the final paving, that would be the time to determine as to whether a  layer of DTp1 might be advantageous. If the hoggin has behaved iteslf, and hasn't turned to goo or settled too badly, then a simple regulating layer of DTp1 or similar quality material might be all you need.

When we know in advance that Mare's Tail is present on a site, we use a membrane such as Terram 1000 or TDP115, laid between the sub-grade and the sub-base, to keep it out of the paving itself, as it cannot force its way through a non-woven membrane. However, all that happens is the damned stuff travels along underneath the membrane and emerges at the sides of the pavement!  

We have had clients who have successfully eliminated it from their patios and gardens by repeated poisoning with Sodium Chlorate or Glyphosphate (eg Round-Up), by cropping it as soon as it emerges, or by blasting it with a blow torch every couple of weeks, but it's a long term task, not something that works in a month or two.

If someone does come up with a miracle cure, they'll have guaranteed their fortune, especially if it can deal with Japanese Knot Weed as well!

It is normally supplied at a low slump, but there's nothing to stop it being poured at, say, a 50mm slump and floated-up to give a close, smooth finish, but, because of the affect of the water/cement ratio, the 'wetter' a concrete, the weaker it is, and, with an already weak concrete, it can compromise the competence of the concrete if it's 'wetted-up' without prior consideration being given to the 7 or 28 day strength.

And so CBMs were introduced. These formalise just what the specifier can expect from a 'lean mix' concrete, making it easier to specify the requisite strength for the job in hand. For the project you describe, I'd hazard a guess that you're looking at a CBM4 or 5 because of the chance of vehicle overrun.

I'm not sure about your concerns over the finish of the CBM. A smooth, steel-trowel finish makes for a poorer bond with the bedding layer than would a coarse, open-textured or rough-cast finish. What are you planning to use as the bedding? A mortar? Think about it - bonding a mortar to a smooth, trowelled surface minimises the surface area contact and the degree of interlock compared to bonding a mortar over an open-textured surface, where it will find its way into the voids and interstices, creating a better long-term bond.

Has that shed any light on the matter?

That the top layer of the actual concrete is iffy is more of a concern, and, from what you describe, it sounds as though the concrete has 'settled' while in place, with the coarse aggregates and cements settling out faster than the sands and fine aggregates. Was a vibrating poker or beam screed used during the placement?

If you're seriously worried, bring back Mix-a-mate (I never did trust those on-site mixings - give me a QSRMC-accredited firm, anyday!) and see what they have to say for themselves.

It's pretty likely that the footings will be sound enough to carry the walls. Given the dimensions you quote, they can only be relatively low decorative walls, and so I wouldn't worry too much. However, if you can push a screwdriver into the surface more than 25mm, then get Mix-a-mate out and ask tham to explain.

Have you been given a spec?

100mm on 150mm of sub-base is the minimum I'd recommend. This 'spec' is illustrated on the Concrete Hardstanding page.

Any chance of getting a photo then we can see it better?

Wodjer fink?

You're not obliged to use the same finish on both sides of the wall, though. You could have the pebble-dashing on the outside and have a smooth finish or whatever you fancy on the internal face. It's your wall - have what you want!  

What sort of gates will you have? Wrought iron?

The drains, I'm afraid, are down to you, and, because of the limitations imposed by manholes elsewhere, you might have to 'live with them', but the gas, lecky and 'phone should be at least 300mm deep. At 150mm depth, they are within the construction layer, which is a bit naughty.

For the fill, you could build up with, say, a SF2 (selected fill) compacted in layers not exceeding 225mm thick, and then top that off with 100mm of DTp 1 or 2, cover that with yer damp proof membrane (visqueen or similar) and then your concrete which needs to be at least 100mm thick. The type of concrete and any reinforcement depends on the use to which this pavement will be put, but, for 22 m², I'd probably use fibre reinforcement rather than mesh steel and rebar.

SF2 is a clean, inert, competent material that is cheap and available locally. Here in The Occupied Former Territories of South Lancashire, it tends to be a crushed Red Bunter/Keuper sandstone, but in North Wales, f'rinstance, it can be a slate waste, and in Cornwallshire it might be quarry waste from the granite industry. In aggregate-poor parts of the nation, such as London and the south-east, it's often a crushed concrete or brick. That's the whole idea behind SFs - they need to be summat cheap and readily available in the local area.

The dpm goes beneath the concrete, to prevent the mix water be drained from it before hydration has taken place and to protect the concrete from any aggressive ground water once it's cured - see the Concrete page for a fuller explanation.

In hot weather, we sometimes place a temporary dpm over the surface of freshly poured concrete to prevent it drying out too quickly and thereby maintain strength and reduce surface micro-cracking, but that shouldn't be necessary at this time of year.

The best tool for cleaning up mortar stained brickwork such as you describe is a needle gun, which you should be able to hire from any decent Hire Centre, but be warned, it's slow, tedious, soul-destroying work.

For cutting out the joints, you need a nangle grinder. You can now get special 'mortar raking' discs that are around 9mm wide, just wide enough to rake out standard mortar joints in one pass. You'll also need a decent pair of goggle and a dust mask, as cutting out pointing is one of the nastiest jobs in the building trade.

Have you considered asking the pointing brickie to undertake the lot?

Here's a picture I've scanned in from the Hewden Hire brochure. If you hire from them, I'm sure they won't mind me mis-appropriating their image.....)

I can't help wondering if your pet Brickie's cough is a result of too many pointing jobs where he's had to do the raking out!

The same goes for sand. 70mm of a Mersey Grit gives around 50mm of compacted bedding, but a quarried sand might need 80mm. And moisture content has an effect on compaction, too.

Only onsite trials will tell you what uncompacted depth you need, but, tonnage can be calculated fairly accurately in advance, if you know the areas involved. The info is given on the sub-base and screeding pages.

In a word; you're buggered.  

To avoid grounding problem, I'm not sure if there is an 'official' recommendation, but the one we always worked to, and I saw it repeated in an article about speed humps in one of the trade publications last week, is that there should be no high point more than 100mm above a flat bone in any 3m run.

If we take a point on top of the crossing kerb, A, and a point on the driveway 3 metres from A, which is labelled C, and we stretch an imaginary tight line from A to C, then the height of the summit point, B, should not be more than 100mm above that line. In the sketch below, it's shown as 65mm, but that's just the figure that came out in the CAD system, and is meaningless in this example. It might be 50mm or 99mm - it's just a figure.

I've been trying to find my reference for this figure of 100mm over 3metres, but I can't think where it might be. There's nowt in my site notebook, so if I get time tomorrow, I'll check SHW and see if it's in there.

The only exceptions that spring to mind are if the road is unadopted, and therefore not the responsibility of the LA, or if they can show that the damage was caused by a known party, sometimes the householder, or an agent of the householder, such as a builder undertaking work at that address.

As for the bark covering, there are all sorts of regs covering minmum depth of cover depending on the height of the equipment within the play area, but, generally, for any area with a tower or chute, then you'd need at least 300mm of approved bark over a membrane. The ground beneath will need to be cleared of any vegetation, and it's often a good idea to incorporate some method of drainage beneath the membrane to ensure the bark doesn't get saturated and isn't sitting in retained surface water.

If this is your own gardenn, then you can get away with more or less whatecver you want, but if you intend the are to be used by members of the public, such as in a pub playground, then you definitely, absolutely must check the Regulations or you could find yourself in all sorts of bother. SAPCA (see Playground Links Page) would be able to advise.

Clear the existing vegetation and excavte to formation level, if necessary. Put down a layer of sand about 25-40mm thick and rake it level. Place a membrane such as Terram or similar, and then cover with 200-300mm of play-grade bark, and that's all there is to it. You may well need some form of retainer at the edges, and the bark will need topping up over the next few months, so buy in extra.

As for drainage, it's essential if what you have is effectively a 'pit' in a clayey patch that will hold water, but, if you're in an elevated spot, then it should be ok. The simplest drainage is to put in a couple of lengths of perforated flexi-pipe and link them to an outfall somewhere, They only need to be laid 100-150mm below the membrane I mentioned, and the typical detail is given on the Land Drain page. In an 8x8m area, I'd do two diagonals and then a link from the centre to the outfall, which could be a point somewhere downhill or an existing drainage system.

Am I going too fast for you, or can you follow my train of thought, so far? Just ask if I'm baffling you with science.  

To achieve 1 metre of lift, you might be better doing two 500mm lifts, stepped back by, say 450mm or so. Do you know what I mean or do you need a sketch?

Anyway - for backfill, I'd go for whatever cheap fill material was available locally. It might be crushed rock, old hardcore, clay or summat more sinister, but you can use that for the bulk fill, cover it with a membrane, and then put 200-300mm of decent topsoil over the top, if you want to grow summat like a lawn.

25 linear metres at a nominal 4.5m wide and a 1m lift makes 50-odd cubic metres of fill. Reckon on 25m x 4.5m x 0.2m for decent soil, which is 22m³ (40 Tonnes) and that leaves 30 cubes for fill, say 60 tonne. I hope there's plenty of air in your wheelbarrow tyre!