My son lives in a small block of flats with a flag covered courtyard at the rear. There are two trees in the courtyard which have gradually grown to about 60 feet and the roots are making a huge mess of the flags, lifting and cracking, leaving gaps in other places. It is a conservation area so touching the trees is not allowed. Any suggestions about how to re-lay the flags or a new surface which will be less susceptable to root disturbance because it will have to done sooner than later as it is getting dangerous in places. Thanks, Col
