Damp in brick outbuilding - new house

daugapils

Hi everyone

I just bought a house which has a brick outbuilding in the garden that previous owners have used as an office building for their business. I have always been living in flats and finally got a house and now I need to figure out all the aspects of lookng after it as well as fixing possible problems.
I am keen to use the this outbuilding as an office too - it looks solid and pretty new with proper corrugated roof , double glazing windows/doors, electricity+heaters, and even a bell that rings ( insancely loud) when someone uses a main bell at the front door.

However there is a damp problem that I noticed pretty soon as you can see from the photos. The damp is located around one corner of the building, between the windows and can be seen in multiple places from floor to ceiling. I can also see some bubbling paint on the outside closer to the roof on one of the affected walls. Stangely there are no ventilation holes visiblle inside and it gets stuffy after a while if you have a heater on. I suspect that's not helping the damp problem at all. I can surely open windows more often but the lack of ventilation holes is really strange. There is no trickle vents or any other ways of air the space.

I have contacted damp proofing company and sent them some photos, their suggestion was to contact a roofer.
At this point I am in doubt if I should start poking randomly at different kind of trade specialists if I can't figure out what is the actual reason for the damp.
I suspect there may be an issue with gutters at least as I can se some black traces on the wall that may mean overflowing water.
I was hoping someone here could point me out in a right direction, i.e. what kind of specialist shoudl I reach out first to avoid waisting mine and their time?

Thank you!

Ectophile

That looks a very odd roof - corrugated at one end, but felt at the sides.  Given where the damp is coming in, it's an obvious culprit.

Do you know what construction the walls are?  If it's solid brick, then damp is more likely to be a problem, so the rendering needs to be good and the roof mustn't leak.

Jeepers_Creepers

'Proper corrugated roof'... :-)

That is serious water penetration - a lot more than lack of ventilation. The starting point is surely as Ecto says - get that roof sorted properly; recovered from scratch, and check it has decent insulation in there while you are at it (min 50mm Celotex, more if you like).

If the roof joists are rotten and need replacing, then extend the new ones a good bit further so they provide a good overhand over the walls. Think seriously about extending significantly over the front door - a couple of feet or so - and make it a feature - perhaps even install downlights there. You can stick with corrugated, although 'box' profile in anthracite will look a lot better. Or get quotes for EPDM and GRP (ideally the latter).

Basically, since it needs sorting, look at the aesthetics too - you won't regret it. Eg, PVC facia boards in anthracite or black finish, that sort of stuff.

I would lay odds that most, if not all, of that water is coming in at roof level. (I hope the electrics are RCD protected?)

Ganga

There appear to be water marks on the outside close to the guttering ,have that checked as well.

Jeepers_Creepers

Yes. Almost certainly from the same source - the roof.

naf123

The roof looks like it has a design fault. You are probably best off ripping it off and start again with a new roof . Follow Jeepers Creepers advice . 

Doozergirl

You don't need to poke at different specialists. 

"Proper corrugated roof" isn't a thing when you're looking at those photos.  

The walls are sopping wet from above.   Re-roof properly with insulation, please, then run dehumidifiers for a couple of months, at least, and then have another look.    

Fix the problem, allow it to dry.   Hopefully rectify the damage caused easily, when it is dry.  

fenwick458

what an odd shaped little outhouse.
It's either deceptive photographs, or the roof joist are 2" at the most. I'm a bit puzzled by the slope too.