High humidity - new insulation or wet weather?

[Benjseb]

A quick update

 

 Ow our heating has been running for the last 5 weeks 24/7 (ASHP) at 18-19c we’ve noticed not a huge difference, maybe high 70s to low 70s

 

weve started running a dehumidifier downstairs that’s under specced but has kept the humidity down to 60-65%
 

Im thinking that adding a PIV unit (or two, big house) may get that down to mid fifties to make it less of an issue? We already have 4xDMEV trickle extractors so can work in conjunction with them. 

 

if so, am I right in thinking that’s Best to situate the PIV inlet in the dryer end of the house, so it pushes the damper air out around the source rooms, rather than pushing it into the dryer rooms?

Also seen our trickle vents are just two 8mm holes drilled in the frame of each window! Can’t see them doing much as the resistance will stop much flow. Might have to drill some more holes out

 

Ben