Damp in Annexe

[otronics]

Hello.

I have an annexe attached to an old house (built late 1800s). The annexe of course is newer but still several decades old.

The previous owners added timber frames, plasterboard and then tiles inside due to damp.

I have removed all this and old plaster.

It has then been replastered.

Some damp persists.

I have tried damp-proofing paint and similar products to no avail - damp is still coming through.

All other issues like blocked guttering etc have been eliminated.

Outside, the wall is rendered. Is this the cause of the problem - walls not able to breathe?

I can attach photos of the damp - let me know if that will be helpful.

[wes56]

photos of the inside wall where the damp persists and the outside showing the rendered walls.if you have replastered with gypsum plasrer its bad, you shoud replaster with a sandandlime render.
is the floor solid and the walls?

[otronics]

The floor in concrete.

Wall is single layer brick.

Not sure what type of plaster was used.

Photos inside and out:

[wes56]

no matter what youdo, with that single brick wall and solid floor youll get constant condensation. do you have a extrcter in the room?penetrating damp thro the wallis also goingon and the eavesof the roof are not sound,can you take a photo of the roof from above the eaves and one showing the verge just above the rwpipe?
cut the render back at least 2 inches from touching the ground, if theres a DPC in the wall then cut back to just above the DPC.
is the inside floor higher thn the outside ground?

youprobly have cement render maybe with non masonry paint and gypsum plaster inside. your best thing is sand andlime render inside and outside.

[otronics]

no matter what youdo, with that single brick wall and solid floor youll get constant condensation. do you have a extrcter in the room?penetrating damp thro the wallis also goingon and the eavesof the roof are not sound,can you take a photo of the roof from above the eaves and one showing the verge just above the rwpipe?
cut the render back at least 2 inches from touching the ground, if theres a DPC in the wall then cut back to just above the DPC.
is the inside floor higher thn the outside ground?

youprobly have cement render maybe with non masonry paint and gypsum plaster inside. your best thing is sand andlime render inside and outside.

* No extractor fan but there is a vent.

* The roof is was constructed two years ago and has no leaks. It replaced a flat roof. Water drains into the (new) guttering fine.

* No idea if there is a DPC. I'll only find that out if I chop back the rendering.

* The inside floor is much lower than the outside pavement.

* Yes - outside is cement render.