Wondering if anyone can give advice. Brought a new house 1920s so no cavity what so ever. Red brick with cement on top. Having such trouble with humidity levels in the upstairs. We have put 2 bedrooms on the side of house and opened it up. We have put a completely new roof on made sure we got the most breathable felt there was but still the humidity levels upstairs are above 70. All bedding feeling damp all the time and clothing. We had a PIV installed which helped slightly but not a lot. Any advice would be great how I can get rid of this issue.