Posted: Fri Apr 21, 2006 9:26 pm
Hi folks,
I'm after some advice I you can help.
Situation just now is that I have an existing patio made up of 3x2 concrete slabs. As it is just now, it's about 30 feet in length (the length of the side of the house), and about 5 feet wide. but fairly uneven in places. The exisiting slabs don't look too great, and having obtained, from a friend, some nice 18"x18" slabs, I figured that I'd lift these existing ones and lay the smaller, but nicer looking ones. I should also say this patio is only used lightly, no cars or heavy equipment near it.
I have lifted one of the existing 3x2 slabs, and found sand beneath it, therefore I assume, there is a sand bedding beneath them all. I will have to remove some of this bedding to even out the level at one side, as due to the aforementioned uneveness, the existing slabs are less than 150mm from the dpc in places. But generally its fairly level, so...
Is they any reason that why I shouldn't just lay these smaller slabs directly onto the existing base, with some additional sharp sand to even the level, after I remove the 3x2's? Or do I need to add some kind of dry cement/sand mix bedding? Or do I bed the slabs with mortar/cement?
Also, I plan to extend the patio in depth to around 8 feet, covering what was a 3 ft wide, cultivated flower border. If I pack the soil in the border down well, and use sharp sand to raise the level as required, should I be safe enough to lay the new slabs onto this base?
Assuming above is ok, I have two remaining questions. Firstly, what fall over the 8ft should I aim for to ensure adquate drainage? Secondly, I had aimed to lay the slabs, butted right up to each other, in fact touching in places, I guess. Is this a problem? Should I leave a actual gap betewwn them? And should I use any kind of wet/dry mortar between them, even considering the, intended, very close proximity of the slabs to each other, or is it not required? Or maybe just brush sand between the joints?
A lot of questions, I know, but any advice, on any point, that anyone with experience of this, has to offer, would be greatly appreciated. Thanks in advance to anyone who takes the time to read and reply.
I'm after some advice I you can help.
Situation just now is that I have an existing patio made up of 3x2 concrete slabs. As it is just now, it's about 30 feet in length (the length of the side of the house), and about 5 feet wide. but fairly uneven in places. The exisiting slabs don't look too great, and having obtained, from a friend, some nice 18"x18" slabs, I figured that I'd lift these existing ones and lay the smaller, but nicer looking ones. I should also say this patio is only used lightly, no cars or heavy equipment near it.
I have lifted one of the existing 3x2 slabs, and found sand beneath it, therefore I assume, there is a sand bedding beneath them all. I will have to remove some of this bedding to even out the level at one side, as due to the aforementioned uneveness, the existing slabs are less than 150mm from the dpc in places. But generally its fairly level, so...
Is they any reason that why I shouldn't just lay these smaller slabs directly onto the existing base, with some additional sharp sand to even the level, after I remove the 3x2's? Or do I need to add some kind of dry cement/sand mix bedding? Or do I bed the slabs with mortar/cement?
Also, I plan to extend the patio in depth to around 8 feet, covering what was a 3 ft wide, cultivated flower border. If I pack the soil in the border down well, and use sharp sand to raise the level as required, should I be safe enough to lay the new slabs onto this base?
Assuming above is ok, I have two remaining questions. Firstly, what fall over the 8ft should I aim for to ensure adquate drainage? Secondly, I had aimed to lay the slabs, butted right up to each other, in fact touching in places, I guess. Is this a problem? Should I leave a actual gap betewwn them? And should I use any kind of wet/dry mortar between them, even considering the, intended, very close proximity of the slabs to each other, or is it not required? Or maybe just brush sand between the joints?
A lot of questions, I know, but any advice, on any point, that anyone with experience of this, has to offer, would be greatly appreciated. Thanks in advance to anyone who takes the time to read and reply.
