Woolly Blue
Player Valuation: £80m
Should probably add that we're getting external wall insulation soon. Our neighbours have all said they have or had a similar issue. Ewi helped, presumably by stabilising thermal transfer.
If that's being done before Winter I'd hang fire on a mechanical ventilation system and just get the fans sorted. The external wall insulation will bring the U value of your wall down drastically and the water's much less likely to condense on them.