laying slabs

does anyone know if I can lay new paving slabs on top of a concrete path. We have dug out our garden ready for turfing and have come acroos an old path and decided it would be nice to keep a path. Also how deep should we lay the top soilk and do we need sand first? Thanks

 

Hi Wrexx - you can lay slabs on top of existing slabs but whether you would want to is another matter. Your big problem is the underneath slabs moving and causing your top flags to sink. This link should help:

http://www.pavingexpert.com/faq_layover01.htm

Cheers,

Dave

 

thanx dave forgot to say it is a concrete path that is braking up in parts but is way to long to remove

 

Hi Wrexx,

Personally I would still dig out - better to start with a base you know all about rather than find nasty surprises later on.. but that's just me!

Cheers,

Dave

 

You can buy imitation granite sets on a kind of mesh, if you laid them on sand on top of the path they should be flexible enough to accommodate movement in the path or you can get wooden 'slabs' made from different diameter logs joined together to form a sqare for a more rustic look.

 

Tend to agree with Dave - we've been there, done that.... If you decide to dig it out, then a pickaxe is the tool you need, to undermine it, then you can break (very large) bits off it, and even use as the base of a rockery you had't even realised you wanted!!

 

I have laid hundreds of slabs for people and myself i have laid over paths and driveways however i made sure there was no problem with the exsiting path or driveway if there was any part of it which was breaking away etc i would remove and replace with some concrete first.

The preperation is important to eliminate any problem of movement or sinking after you have laid your slabs on top you can use stone dust or sharp sand about 2- 3 inches whack it down and level it off so that you are laying on flat surface i allways break the bond but its the indivudals choice.

 

Off Topic (sorry)

Golfer, as you posted this pic, may I ask why you have wire mesh under the pots?

Maybe just storing it there, but it looks as if it's there for a purpose; to increase ventilation around pots perhaps?

Just curious

 

Well its not wire but small sections of plastic coated mesh they were on a small portable tubular greenhouse the ones you buy for around �£15 and you have a zipped plastic cover over it.

The plastic sections was where you stood plants on there was three or four if you look bottom right you can see some of the tubes which i used for a staging in the green house put it to some use.

Back to your question they are not under the pots for any reason i just laid them there out of the way.

 

Thanks golfer, I guess that's a good recycling idea, I suppose we all have the plastic pieces left over after the wind has ripped the zipped plastic covers!

Happy Easter everybody, and appologies to wrexx.

 

sorry golfer, not too clear about laying slabs on top of concrete ...... if the concrete is tatty, break it up and start again,
if the concrete has say one crack, presumably this would transfer to the slab above so again break it up
if concrete is ok, so we cover with 2 -3 inches of sand or stone dust, the way i read the post it looked a bit odd?
i was thinking of laying the setts which are on a mesh, on top of concrete path which looks ok but has no edging, how would it "hold"
.. and when you say "i always break the bond" , what does that mean please

[ 14. April 2006, 06:55 PM: Message edited by: Lady Gardener ]

 

Firstly breaking a bond when you have bricks laid on a wall the first course of bricks are laid and when one starts on the next course lay the first brick halfway across the first brick on the bottom course that is breaking the bond take a look at your bricks on house thats of course its built of bricks.

Its the same with slabs lay six slabs or 10 in a straight line and when you start the next 6 or 10 along side of the first 6 or 10 start the first slab halfway down the first slab you laid then you cut one slab in half to lay either end this way you break the bond you have straight lines down but not across.

I am talking about square slabs of course because today you can buy all different shapes and sizes and its a matter of choice some prefer not to break the bond and have a straight joints down and across.

Dave gave you a good link lots of infromation on there also Helen suggests imitation granite slabs with wire mesh never used them myself prefer normal type beleive they are stronger but i dont think you will have a problem laying over exsisting providing you repair any damaged areas that old path you discovered must have been there for a awful long time and should be well setteled regards any further movement.

You are not laying on top of other slabs you have a path which maybe is 3>4 inches thick whatever you decide you will need some edging laid on the sides to prevent any movement from side to side.

One crack should not give any problems neither will it transfer to what is above providing you 2 > 3 inches stonedust or sharpsand level to lay slabs on . But you state you were laying sets directly on top of path which would have to be perfectly level for that, you have to have something underneath whatever you lay othewise they are bound to move a little when walking on them .
If not all clear please reply again.

 

yes thanks, the area i was thinking about is pretty small and lightly used by pedestrians only, i think the prob is going to be puting an edge down as there is a fence very close, also there is a prob with DPC as it is an addition to house, a kind of porch, with no sign of air brick as indicator, am i rt in thinking air brick is generally one brick above the damp proof course?
also the area to be covered also runs along the wall of the house for a metre or so, but is quite high in relation to air bricks, am i rt in thinking if the granite setts-on-mesh were set in sand, there would not be an issue of interfering with the transmission of water across the DPC?

[ 15. April 2006, 07:40 PM: Message edited by: Lady Gardener ]

 

Your paving shold be, I believe 6" below DPC.
Air bricks only occur if its a timber floor, if its solid you dont have any.
The DPC is usually visable in the brickwork.

 

Pete is correct regarding 6"" gap.
Air bricks were installed in pre War council houses as they often had compacted base and tile flooring and no wall cavity,the air brick was four bricks above DPC.12",and visible inside the house.So have a good look and make sure your levels are based on the DPC.