Patio question - (Thermo!!!)

[AndyBill]

how do you think i should go about preparing my patio?
i have a slab of concrete coming out about 4 feet from the house,
and then 2 rows of badly laid slabs.

i want to put anew patio that comes out further than the existing ,
do i have to remove the concrete or can i go over it ?
i will be removing the slabs and putting down MOT (probably?)

do i just compact the MOT level with the concrete then put new slabs over all of it?

do i need to build a little wall to keep the MOT in?

 

[noseall]

provided that, when laid on top of the existing concrete, your new slabs are below the d.p.c by 150mm (usually internal floor level), then you will be ok.

and it will be ok to make up the height difference of the lower slabs by using m.o.t. directly on top of the old ones. if you like you can hit 'em with a sledge hammer. you will need a retainer or edging though because of the height differential.

 

[Thermo]

small wall at the front, its a bit to high otherwise and will look crap if you just render up the face. Lay directly onto the concrete, give it a brush off first, and wet it before laying on them. As noseall says mot to make up the levels. I would give each slab a clonk with a sledge hammer first.

 

[AndyBill]

cheers both

 

[WabbitPoo]

One other thing, when you build the wall, measure carefully so you get a full slab at the front edge. Half slabs or shorter have a tendancy to ping off when walked on a lot, specially if you have then overhanging a little. Plus, it'll look better than having a cut slab at the front. You probably thought about this already.

 

[AndyBill]

ok thanks for that wabbitpoo.

how high do you think i should have the retaining wall?
and what bricks should i use?

how deep should the foundations be?

 

[noseall]

technically, the wall only needs to retain the hard core, so it can finish slightly lower (10mm) than the slab bottom and then allow the slab to oversale the 'sleeper' wall, thus creating a step.

alternatively, the wall could be made high enough for people to sit on, leaving an opening or a step up from the garden to the paved area.

or, the wall could finish at the same height as the top of the slabs, with the wall having solid blue bricks laid on top. this will effectively 'frame' the slabs. by doing it this way you could add shape to the wall and ultimately the paving too.

it's up to you.

the foundations should be about 150mm thick and be at least 150mm wider than the wall, and set at a depth of 450mm below ground level.

 

[Thermo]

its only going to be a couple of courses high if that, it doesnt really need to be that deep, a 6 inch deep strip of concrete, one brick below the ground level will be adequate

 

[Deluks]

Don't forget to lay the new slabs on a slight incline so that rainwater runs away from the house

 

[AndyBill]

its only going to be a couple of courses high if that, it doesnt really need to be that deep, a 6 inch deep strip of concrete, one brick below the ground level will be adequate

do i need to put hardcore in or just 6" deep of concrete?

 

[Thermo]

concrete

 

[ModernMaterials]

Re: bricks.

i notice that wickes are selling red engineering bricks quite cheaply.

i like your cat flap in the wall can i ask what you used to line the middle of it as i am doing one through a cavity wall myself having bricked up the old doorway with the cat door in it.

 

[AndyBill]

thanks for that ,
about the cat flap , i lined it with plywood , 10mm i think,
i just wedged and gripfilled it in and then put a piece of green felt carpet down so they dry their feet on the way in!

 

[ModernMaterials]

lolol thanks for that....

fantastic idea with the carpet for drying their feet

 

[Fluk_Fluk]

Yes it should look great