In message , Sue & Bob Hobden
writes

In that size garden I would, without doubt, take them out. Even if you want
some form of "fir tree" there are some far finer plants you could use
instead.
Leylandi can be trimmed but never look good in the way a Yew hedge would and
there are other alternatives, indeed the Ceanothus I mentioned earlier can
make a fine light hedge if trimmed appropriately.
The only thing Leylandi have going for them is they are quick growing,
however they don't ever stop growing either, I've heard a rumour of some
over 100ft tall and still growing! :-(

Thanks for all the replies everyone, on closer examination there are 5
of these and the biggest one looks as if it's been cut (clean cut at the
top). I suspect the previous owner planted these as a defensive measure
(& for a screen) as there used to be a derelict building at the back
which had an access to the street allowing people to get at the sheds.
The council has since removed this building and blocked access.

--
Ronald Hickey