In message , Harman Sanghera
writes
I have a patio area in the back garden, and also a lot of paving stones in
the front. I have to pressure washer these area regularly due to having a
lot of trees nearby. Some of the joints in the paving stones have come
"apart", i.e. there is no mortar (or whatever was used) in the joints. How
can I replace the joint compound and what with? I want it to be able to
withstand pressure washing which I have to do at least once a year.


I assume that there is a reasonable gap between the slabs? - about 10
mm. (If the slabs are butt jointed like you find on pavements with
concrete slabs then you can't do the following)

They need to be repointed with mortar, scrape out the old stuff and
repoint. I would do this with a wet mortar mix.. You can do it with a
dry mix brushed into the joints, but on already laid slabs with dry
joints I don't think it works as well.

Have a look at:

http://www.pavingexpert.com/pointing.htm
--
Chris French, Leeds