condensation problems

Hi Can anybody resolve the following
I've lived in this house for the past twenty five years and only in the past two years have I had a problem with condensation on the windows and in the loft.
10 years ago I replaced the windows with argon filled dg units which solved the small condensation problem.
2 years ago I had the cavity filled with insulation and this caused minor condensation problems on the windows'
Last year I increased the loft insulation by a extra 100mm but only in the areas which are not boarded now I have a serious condensation problem in the loft with water dripping from the felt under the ridge.
It only happens in the winter as I always check my loft carefully for leaks following any very wet weather which we have had earlier this year.
Can anybody offer advise please

in case of condensation, add ventilation

Has the loft insulation blocked the ventilation gaps at the eaves?

//www.diynot.com/wiki/building:condensation_in_houses

Do you drape wet washing about the house? Do you take baths or showers without running an extractor fan? Have you checked that any water tanks in the loft are cold, and have close-fitting lids? Do you have any holes in the ceilings going into the loft, for example for downlighters or pipes, or a loose loft hatch?

Hi Thanks for the reply
I was very careful to ensure that the ventilation of the roof space was not covered with the insulation but can I add my style of living has not changed apart from having dg replacement windows flitted also cavity wall insulation and increasing the insulation in the loft.
The cavity wall insulation resulted in some condensation on the windows particularly the bedroom we use and the loft insulation has resulted in condensation in the loft space and the loft is noticeably colder than before I may have to fit a dehumidifier as a last result but this rather defeats the object of saving money with additional insulation. Thanks anyway

it's possible the new glazing has fewer draughts than the old, thus cutting (undesired) ventilation.

if you can increase the gaps at the eaves, that will probably fix it; or if you have gable walls in the roof, you can hire a core drill for an afternoon and put a couple of 100mm holes at each end (you can fit plastic ducts and grilles) and this will cure normal amounts of moisture

sometimes just using a bathroom extractor is enough to reduce the moisture load.