The Brew Cabin

Posted: **Tue Apr 28, 2009 12:39 pm**

I originally posted this in the flags section, but it seems to be more appropriate here.

"Hi, I'm new to this site and paving in general so please excuse me if this has already been discussed before, I just couldn't find the answer I needed on the site!

I'm laying a new patio (replacing a lawn area) in my first house and there is a pvc shallow inspection chamber to the edge of where I want to lay the patio. I cannot avoid the chamber altogether as this would make the garden look odd (IMO anyway).

Anyway, I am laying Bradstone's Panache paving slabs and would like to avoid cutting them where I can to preserve their design. Bradstone describe them as butt jointed slabs, which I believe means I don't need to leave a gap between each slab and therefore don't need to fill the gap (correct me if I'm wrong).

What I would like to do is alter the height of the risers in the shallow inspection chamber by an inch or two so that the lid of the inspection chamber becomes level with the top of the blinding that the patio will rest on, then I can lay a dry slab over the top of the chamber lid so that, whilst it is still accessible, it is hidden from view completely.

Would hiding the shallow inspection chamber in this way violate any building regulations? The inspection chamber only serves our property, as each property on our estate (it's a new estate) has its own shallow inspection chamber.

Thanks in advance for your collective help.

Grumpy"

Posted: **Tue Apr 28, 2009 3:37 pm**

Im not sure about violating building regs, but if it only serves your house and you dont forget to tell the next people that move in after you where it is, then i cant see a problem. Might struggle getting it to lie right though.

Not familiar with that particular flag but yes butt jointing is the flags with no wide gaps. (butt jointing is covered on this site)

Are you bedding the flags on sand or on mortar?

Posted: **Tue Apr 28, 2009 3:50 pm**

I haven't decided yet, I've just been reading through the guides and although it recommends a semi-dry mix for DIYers, I really don't want to end up with a wonky patio so I will probably go for either a wet mix or just blob the back of the slabs, what is the general consensus on this?

Posted: **Tue Apr 28, 2009 3:58 pm**

Spot bedding is not a good way of doing.

The best way in my opinion is to lay each one individually on to full bed mortar.

Posted: **Tue Apr 28, 2009 4:16 pm**

Ok so would you compact the sub-base and then put the wet-mix straight onto that or would you put a layer of sand in between them?

slab
mortar
hardcore

or

slab
mortar
sand (or some other blinding if sand isn't right)
hardcore

?

Posted: **Tue Apr 28, 2009 4:35 pm**

Flag
Mortar
hardcore

Sands not neccasary.

Posted: **Wed Apr 29, 2009 5:01 am**

You say you have read the main index and you still want to "blob"? read it again, then re-read it. as for the cover looking out of place, i'm sorry but if we flagged over every cover for that reason there would'nt be any access anywhere. ???

Posted: **Wed Apr 29, 2009 7:46 am**

I meant I had read the index for the answer to the inspection chamber question, I'm still reading the rest of the site (there's a lot to take in for a beginner!). I have now read the part of the site regarding the bedding layer and I agree that blobbing is in fact a terrible idea, for people who are too lazy to do a proper job!

There is one other question I have though which the site doesn't make clear, I'm designing/laying a patio that will only ever have people and furniture on it, do I need to create a sub-base from DTp1 or should I go straight to a 10:1 mix for the bedding layer and make it a little thicker (say 50-60mm after compaction)?

Posted: **Wed Apr 29, 2009 7:55 am**

in 9 out of 10 cases you use a subbase, unless your ground conditions are very chalky/rocky etc any organic matter i.e soil/clay then you need minimum 100mm type 1 compacted.

Posted: **Fri May 01, 2009 6:54 am**

You are leaving yourself wide open for a volley off the gaffer. The answers are all on the main index as clear as day. a lot depends on the size of the paving as to the bedding layer being bound, or unbound. You need to be 40 ml after compaction, and as gb says it depends on the stability of the subgrade as to it warranting a sub base. like others on this forum i mostly always err on the side of caution and lay one.

The Brew Cabin

Panache paving and inspection chambers - Hiding a shallow inspection chamber