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Posted: Sat Feb 05, 2011 3:48 pm
by joycem
I am planning to lay a rigid clay paver patio and adjacent path at the rear of my house with the help of a very experienced bricklayer. (i.e. He will do the work and I will make the tea). The patio will be about 5.5 x 3.2 m and the path about 4.8 x 1.2 m.

On top of the subgrade I plan to have: Terram geotextile; 150mm Type 1 sub-base (I have a heavy clay soil); plastic sheet dpm; 100 mm of C20 concrete; 25mm Class 1 mortar bedding; 50 mm Rudgwick pavers. (Does that sound OK?)

The concrete will be laid as two slabs - one for the patio and one for the adjoining path. There would be a movement joint between the two slabs.

The bricklayer prefers to mix the concrete on-site. But my instinct is to use Minimix or similar for the larger slab and barrow the concrete the 25m from road to site. My concern about on-site mixing is that the bricklayer would, I imagine, take several hours to mix, pour and tamp the 1.8 cu meters needed for the larger concrete slab. This would presumably mean the first mixer-full poured will be setting (or already set?) by the time the last one is poured. I am wondering if that would affect the strength of the slab. Also Minimix can provide fibre reinforced concrete which seems to be an advantage.

Any comments on the pros and cons of the two options would be greatly appreciated.

Posted: Sat Feb 05, 2011 4:03 pm
by Pablo
Hi Joy. A few points firstly clay pavers don't need to be laid on concrete and mortar it's a expensive and not any better than doing it properly with stone base and sand bedding. Also an experienced bricklayer laying paving is no different to my dentist tiling my bathroom if he hasn't got any paving experience then he is a novice and judging by the construction method then I'd say he was. If you look on the main site (click the blue tag on the top left of this page) then all you need to know about how to install block paving is on there. But all you really need is a geotextile then 100- 150mm of well compacted type 1 30mm of course sand and the block. All in an excavation of no more than 230mm give or take and a lot less than the 330mm you were planning. You'll save a lot of money if you do it this way and it'll be much quicker with less things to go wrong and much less mess and cleaning up.

Posted: Sat Feb 05, 2011 4:34 pm
by joycem
Hi Pablo

I want rigid paving with mortared joints, so a sand bedding aint going to be any good.

Posted: Sat Feb 05, 2011 4:52 pm
by digerjones
think you might be wasting your time pablo

Posted: Sat Feb 05, 2011 5:15 pm
by ilovesettsonmondays
a screed bedding will be fine. you dont need wet concrete underneath .if you want to go to an extreme . dig out lay semi dry concrete and use whacker plate on it . lay paving on a screed bed of sand and cement through mixer(dryish) . lay each one individual and clean off with water . . we use this method laying setts in central london with buses , beer wagons etc going over it so your patio should hold up ???. i would point them at the end .there is no need for tamping etc

Posted: Sat Feb 05, 2011 6:29 pm
by dig dug dan
why oh why would you want to lay clay pavers on a concrete bed??
they are not designed to be laid this way, and if you are planning on laying each brick with a mortar joint, why waste money on clay paver's?
In any case, any more than 1 cubic m of concrete mixed by hand is not cost effective
Fibres in the mix do nothing to add strength , they merely stop "plastic cracking", and if you are covering the slab up, is a waste of time in this instance
It strikes me that the brick layer has given you this spec for some reason?
Follow pablos advice, as it will save you money, time and will look neater.

Posted: Sat Feb 05, 2011 6:56 pm
by GB_Groundworks
hand mix tends to be weak and to wet especially if a brickie is doing it, get barrow mix company theyll barrow it for you.

are you planning to land 747 on your patio hehe seem like an awful amount of overkill and extra expense, but its your money and time to waste.




Edited By GB_Groundworks on 1296990064

Posted: Sat Feb 05, 2011 8:15 pm
by lutonlagerlout
madness

other than this readymix is nearly always better than mixer made

massive overkill on all fronts, TBH if you want rigid (why oh why?) then better to get floor screed delivered and laid then lay the pavers straight on to the screed before its set
pointing could then be done with a slurrymix and cleaned

at the end of it all its your money,but I would suggest if you have gone to this overkill you may as well use instarmac gunpoint or easipoint as that way your mortar joints will be the same colour
I take it the area can be covered while the pointing is going on?
because a sudden shower and its over

also have you considered drainage?
a rigid patio will absorb no water

good luck
LLL

Posted: Sun Feb 06, 2011 8:25 am
by seanandruby
:O ??? :p

Posted: Sun Feb 06, 2011 5:20 pm
by rab1
Maybe the man is building a Mobile Crane yard, abaita small one. ???

Posted: Sun Feb 06, 2011 6:36 pm
by joycem
Thanks to those who have made constructive comments; they are all appreciated. In response I have some additional information:

1. Why Oh Why Rigid Paving?

Well I am looking for an patio with an attractive appearence, and IMHO clay pavers with mortar joints look vastly superior to the other options. Also they should be lower maintenance than the alternatives.

2. Patio is overengineered

Tony gives guidelines on the construction of rigid paving see - http://www.pavingexpert.com/rigidbpv.htm. You will see that my plans are broadly in line with these. However he does state that a sub-base may be omitted for low-traffic or pedestrian-only pavements, so perhaps I should lay the concrete directly on the sub-base.

3. Drainage

The patio will fall towards a lawn, and will drain over the longer (5.5 m) edge. I currently have a slightly smaller patio of slabs that seems to drain OK. The are no puddles in the lawn after rain and no moss build up on the lawn. The lawn slopes slightly away from the patio which probably helps drainage.

Posted: Sun Feb 06, 2011 6:42 pm
by dig dug dan
at the end of the day, its your money, your job. we can only advise.
deffo readymix though. not mix by hand!

Posted: Sun Feb 06, 2011 6:50 pm
by ilovesettsonmondays
we are all only trying to save you time and labour and money

Posted: Sun Feb 06, 2011 6:52 pm
by ilovesettsonmondays
your patio is being done to an extreme that is fine , dont get me wrong , but doesnt need to be done in that way

Posted: Mon Feb 07, 2011 10:00 am
by joycem
OK I'll certainy use ready mix. But ilovesettsonmondays and dig dug dan, it would be really helpful if you give me a few more details on how you would construct a patio with clay pavers (102 x 215 x 50mm) and mortar (or a mortar lookalike alternative) joints. I will need more detail than you have already provided - the depth of each layer for example. My soil is quite a heavy clay.
Thanks in advance.