On 01/01/2021 11:18, wrote:
Hi all and Happy New Year,

I'm trying to find the best solution to a condensation problem in a
loft in a 1980's new built block of flats (top floor flat with loft
access).

The condensation forms on the inside of the roofing felt then drips
down onto stuff stored up there. The loft is well insulated just
above the ceiling. I don't want to increase ventilation due to water
pipes being up there (as I don't want frost damage).

The simplest solution would be to improve the ventilation of the loft
space and/or the impermeability of the vapour barrier between the
occupied space underneath and the loft.

You can't really prevent the roofing felt from being cold so you have to
get the humidity lower somehow.

Prevent moisture getting in or allow more fresh air to displace it.

Maybe some sort of screen fitted over the rafters or some kind of
insulation between the rafters? What would people suggest as a cheap
and easy to fit solution? It does not have to look good.

The condensation you describe is capable of allowing serious rot to
develop in roof timbers as well as cosmetic damage to stuff it drips on.
Advice on Usenet may be worth less than you have paid for it...

--
Regards,
Martin Brown