laying pavment slabs on to old bricks should not be a problem as long as you make sure that they are not sticking up,make sure that the large bricks are broken up and that thay lay flat,put a littel sument or morter in each corner where you are going to lay your slabs so they do not move when set,then brush some morter between the cracks of the pavment slabs,this is what i did when i moved in to a new house,i had all the lod bricks under the lawn,so this is what i did to get ride of the bricks,now i have my greenhouse standing on it.
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