The Brew Cabin

Posted: **Sat Oct 10, 2009 2:29 pm**

Dear Brew Cabin members,

I am currently designing some steel access covers which will have blockwork laid within to complement the surrounding street paving. The likely paving block size is 200mm x 100mm (block depth is not a problem in this situation)

I am told that standard blocks incorporate spacing bumps and that the 'nominal' sizes usually refer to the 'pitch' of fully butted-up blocks and that to place 2 rows of blocks side by side I would therefore only need an internal tray width of 200mm. This strikes me as not allowing any leeway and I am inclined to add a bit and make it more like 205mm.

I have tried verifying this dimensional aspect via Internet searches of block manufacturers but have not been able to find any useful information.

It would be good to hear from anyone who actually has to do this kind of work and to get their opinion of what sort of allowance should be made in order to provide a sensible and workable design for the guys at the sharp end of the installation. IE - should the width allowance for each block be - 100mm, 102.5mm, 105mm or more? - or indeed should it be a fixed allowance per array (say 210 for two rows but only 310 for 3 rows)?

I hope I have explained myself well enough!

Any comments gratefully received.

Posted: **Sat Oct 10, 2009 2:52 pm**

It seems you are designing the cover to one specific size of material. what if we want to use 300x300 setts, or other forms of paving ???

Posted: **Mon Oct 12, 2009 8:38 am**

Ah.. well, this is exactly the kind of problem I am trying to address. My client tends to want to make things in nice round numbers for the overall structure - which, in my opinion, ends up with odd sized apertures for people to fill with blocks of some sort. Now obviously, no two installations are the same and I reckon that these things need to be customised to suit where possible. However, to do that, I still need to have a basic principle to start with and as I figured that 200x100 are the most common sized block in the kind of application I am dealing with, it would be good to start with that. If I can personally build up some degree on knowledge with the various blocks then I hope to be able to design things that don't make the installation guys think I am a complete idiot!

Cheers for the response and if you feel like enlightening me with regard to other block types then that's great as I am eager to get things right.

Adrian

Posted: **Mon Oct 12, 2009 10:46 pm**

You're thinking too hard about it because the blocks will always need to be cut so that the overall pattern can be maintained. It is not possible to lay to a cover and continue through it wthout cuts because the cover lip itself is usually 10mm wide. Make them to fit the holes and let the pavers sort out the finish.

Posted: **Mon Oct 12, 2009 11:00 pm**

a sensible answer there "pablo" the lid fit the hole let the paving fit the lid ,how ever you make the lid the has to be cuts to account for the frame thickness, pavers are used to cutting into lids MSH

Posted: **Thu Oct 15, 2009 11:45 am**

OK guys, I'll attempt to stop thinking too hard and let the likes of you do all the difficult and arty stuff on-site - but I will carry on TRYING to be helpful instead of going ahead and designing stupid things all by myself

Cheers for now,

Posted: **Thu Oct 15, 2009 7:43 pm**

unless the overall rim width was less than 4 mm it wouldnt work, as has been said it just needs attention from the pavers to doing neat cuts
regards
LLL

The Brew Cabin

Paviour spacing - I need some advice/opinions