Is my decking causing damp issues?

[Skibbzy]

Hello - I moved into a 1961 property 3 years ago and it had some decking already installed. Please see photos attached

Last winter and this winter we are getting damp at the bottom and lots of wet beading at the top of the door on the inside. Would your expert opinions put this down to the decking?

If that is the case - would taking the decking out rectify the issue or will more work be required after this?

Also we are getting mould on the ceiling above - is this all related?

Thanks in advance for any advice

 

[Why Not Indeed]

Where's the DPM?
Is that decking blocking any air bricks?
It seems unlikely that the decking is going to be the source of so much moisture ingress that you have mould on the ceiling, BICBW. Is that ceiling a little porch extension? Maybe need more insulation in there in that case.
Algae on brickwork is usually a sign of moisture. But there's more on the wall where the decking isn't than where it is.
What's the floor like near that door? If it's timber, does it feel damp or even soft/spongy?

 

[Skibbzy]

Where's the DPM?
Is that decking blocking any air bricks?
It seems unlikely that the decking is going to be the source of so much moisture ingress that you have mould on the ceiling, BICBW. Is that ceiling a little porch extension? Maybe need more insulation in there in that case.
Algae on brickwork is usually a sign of moisture. But there's more on the wall where the decking isn't than where it is.
What's the floor like near that door? If it's timber, does it feel damp or even soft/spongy?

Thanks for the response - I can't tell where the DPM is and I'm not sure if it is blocking air bricks to be honest. The screws are difficult to remove so I have acquired some extractors to hopefully the remove the ones closest to the house and inspect

The ceiling is a single extension but it is a little isolated in the corner - maybe it does lack insulation in the roof of it I will try and inspect that too. But access would mean roof tiles off or removing the plaster ceiling!

The floor behind the door is tiled (again there when we moved in) so unsure in the floor state underneath. I've not noticed in movement in the tiles but they do get wet/mouldy too.

The joys of homeownership

 

[foxhole]

Decking is breaching dpc and may cause lower damp issues, but uninsulated unventilated hall will cause the mould and condensation.
Any problems with roof and gutters?
Is this near kitchen ? Do you dry clothes indoors.?

 

[Murdochcat]

There is a multitude of things that could contribute to this and adding to the above how well is your home ventilated and how well do you heat it ?

 

[Why Not Indeed]

But access would mean roof tiles off or removing the plaster ceiling!

Not sure about the construction of your roof/extension there. But you've got a relatively straightforward, small square area of plasterboard you can remove in order to get into it and stuff some insulation up there. Reinstating it would be easy enough, square of plasterboard, hide the edges with some replacement coving. No wet plastering required at all. You could even put a square of PIR foam above the plasterboard.

Having said that, your first priority is to work out if there's any moisture ingress from outside, as it could lead to something catastrophically expensive in the long run. Poor insulation "only" means patches of mould and higher fuel bills.