In message , John
Rumm writes
Steve Jones wrote:

But is it the wrong time of year to be doing this? Will having it
done in cold weather shorten the life time of the new roof? I am
thinking of expansion and contraction throughout the year.

When I had the roof on my new dormer done (July ish IIRC), the chaps
doing it said they much prefer doing it in the cooler weather since it
is so much cut the felt when its not all hot and soft (also much
simpler to strip old felt when it is a little brittle). Since it is all
bonded with hot tar, I doubt the ambient temperature will make that
much differnce from a longevity point of view.


The chap who did ours last year was doing it in July when the weather
was scorching poor bloke.

Also my current roof is green mineral felt. Had a couple of quotes,
one guy would replace with green mineral. The other with green
mineral just around the edges, then something else in the middle
(can't remember name) which is then painted with some silver stuff
which reflects the sun and stops expansion/contraction problems.

That is what they did on ours. Very neat job, As you say they just used
mineral where it will be visible from below, plus about 6 inches of
roof The rest was done with a smooth top felt and then mopped over with
the silver finish.

Which is better? Which is actually more expensive?

The silver finish is better, and in our case was no more expensive. You
have other options, fiberglass is one, there is also a rubberised
coating option that is supposed to be good (although that will add at
least 50% to the price).

If I was going to be living in a house for some time then I would
consider using either a fibreglass covering, or a butyl rubber cover.
Both should have a longer life span than felt
--
Chris French, Leeds