Hi,
We have a 15th/16th century granite flagstone floor. After heavy rain water pushes up between the flags. There is no way I want to lift the floor, but I have raked out all the joints to about 50mm deep and the water is now draining well to one side where we can get it out of the building along an internal gutter.
My question is... How should I grout the flags again so that the water can still drain away under the grout? What material should I use? Gaps are anything from 2mm to 20mm wide. If possible I want something that will not draw the damp up like a wick.
One thought I had was to put an inch of salt underneath the grout - which would dissolve to leave a channel for the water to drain along - but will it just wreck the grout and leave me with a fluffy floor?
Thanks
We have a 15th/16th century granite flagstone floor. After heavy rain water pushes up between the flags. There is no way I want to lift the floor, but I have raked out all the joints to about 50mm deep and the water is now draining well to one side where we can get it out of the building along an internal gutter.
My question is... How should I grout the flags again so that the water can still drain away under the grout? What material should I use? Gaps are anything from 2mm to 20mm wide. If possible I want something that will not draw the damp up like a wick.
One thought I had was to put an inch of salt underneath the grout - which would dissolve to leave a channel for the water to drain along - but will it just wreck the grout and leave me with a fluffy floor?
Thanks