Hi all
I have an old extension, 60s house, 70s suspected extension. I think it is on a 'raft' foundation. You can easily dig under this 'footing' all around the extension and it isn't very deep. It's about a brick thick, and it starts one brick below the house DPC.
I aim to do a patio around this that ends at the top of the footing so it is all contained. It is unfortunate that it will be one brick below DPC but I don't have much choice in the matter here.
The top of the 'footing' is flat on two sides but on one side, it has had mortar and concrete poured onto it, I think from a previous path. This was all bobbly and different heights, so I've ground that down to remove the unsightly vertical protrusions. I ground this down figuring this is the least destructive method, with the least risk to the concrete footing below.
My plan is to 'haunch' on top of this concrete footing/the ground down surface on top of it- basically put a triangle of mortar along its length so that water that falls into it is directed into the ground, and it is more sightly than unfinished concrete.
As I ground down I found gaps in the cement where dirt and moisture has got in. I was planning to 'haunch' over the top but I'm not sure if I should remove all this concrete mess on top to get rid of all moisture first.
My plan is to use SBR along the top of what is there, and the visible brick on the wall.. mortar mix and cover the vertical bricks so the rendering is complete as currently it is all wobbly and bricks show through; I suspect when this was done, someone rendered down to the dirt/stones! Once that is done I will do my triangle of 'haunch' along its length. I'm not sure whether to use Thomson's Water Seal before I apply any mortar, after, or perhaps both, to be belt and braces against any water ingress.
Hopefully photos and diagrams will illustrate what I mean- what do you think? My main concern is - should I remove all the old mortar on top of the footing first, shall I apply water seal before applying any mortar?
I have an old extension, 60s house, 70s suspected extension. I think it is on a 'raft' foundation. You can easily dig under this 'footing' all around the extension and it isn't very deep. It's about a brick thick, and it starts one brick below the house DPC.
I aim to do a patio around this that ends at the top of the footing so it is all contained. It is unfortunate that it will be one brick below DPC but I don't have much choice in the matter here.
The top of the 'footing' is flat on two sides but on one side, it has had mortar and concrete poured onto it, I think from a previous path. This was all bobbly and different heights, so I've ground that down to remove the unsightly vertical protrusions. I ground this down figuring this is the least destructive method, with the least risk to the concrete footing below.
My plan is to 'haunch' on top of this concrete footing/the ground down surface on top of it- basically put a triangle of mortar along its length so that water that falls into it is directed into the ground, and it is more sightly than unfinished concrete.
As I ground down I found gaps in the cement where dirt and moisture has got in. I was planning to 'haunch' over the top but I'm not sure if I should remove all this concrete mess on top to get rid of all moisture first.
My plan is to use SBR along the top of what is there, and the visible brick on the wall.. mortar mix and cover the vertical bricks so the rendering is complete as currently it is all wobbly and bricks show through; I suspect when this was done, someone rendered down to the dirt/stones! Once that is done I will do my triangle of 'haunch' along its length. I'm not sure whether to use Thomson's Water Seal before I apply any mortar, after, or perhaps both, to be belt and braces against any water ingress.
Hopefully photos and diagrams will illustrate what I mean- what do you think? My main concern is - should I remove all the old mortar on top of the footing first, shall I apply water seal before applying any mortar?
