On Dec 9, 11:07*am, F news@nowhere wrote:
Went up into the loft yesterday to retrieve Christmas decorations and
found that the tops of the spars on the north facing pitch of the roof
were damp/wet. If I touched the felt then water drops appeared.

The south facing pitch appeared to be dry.

Could it be condensation caused by the colder north facing tiles which
might, possibly, still have snow on them? I increased the insulation
quite significantly earlier in the year.

You've made the loft a lot colder (less heat escaping from below),
making condensation more likely.

You need to ventilate the loft space better.

MBQ