Damp - all sorts

[KarronR]

Hi there, new on here so please bear with me!!
I live in Greece, our house is about 60 years old and was built just after a huge earthquake demolished the area. It was built fairly quickly to rehouse the homeless. Houses here are built by pouring concrete into a wooden shell which contains flexible metal supports to protect against earthquakes and only the very new ones have any type of damp proofing.
We are experiencing the following...
Damp/black mould on the inside of all exterior walls, which seems to drift onto the interior walls in some places.
Bad condensation on most of the windows which are a mixture of wood and uPVC.
Bubbling on the walls in 1 of the bedrooms
Our entrance lobby and hallway is the worst, I have to bleach the walls regularly and we literally get so much condensation that it runs down the walls and we get big puddles on the floor.
The house is a single storey with a garden front and back. The owner did tell us that he had replaced the flat roof a few years ago with a tiles sloping roof because of leaks.
We are currently considering buying it, but wanted to know how much work and how expensive it would be to fix this problem. Local builders here have given us so much conflicting advice we don't know what to do.

Thankyou for any help you can give us.

 

[Blagard]

You are a brave soul for posting on this Site! - While it does sound as if your dampness is mainly condensation related, any aspect of construction in Greece would just be pure guesswork to me!

The battle with Condensation is fairly straightforward. Heating and Ventilation are the first two allies. If a house is sealed up tight, just breathing in it will raise the level of humidity. You must allow ventilation. Heating will allow the air to hold more water before it condensates out and will warm the structure also reducing condensation. In some cases just heating and ventilating can get rid of condensation. You must do both as a minimum.

I've no idea if you are in the mountains or near the sea but to minimise the cost of heating and to increase surface temperature of you walls you may need to add insulation.

Simply put, add to walls from inside, insulation, vapour barrier, new wall lining in that order. In some places you can insulation the outside of the structure instead but I don't know how they build over there so it may not be practical.

Getting some books on construction as used over there may help but would be no good to me as it would all be just greek to me (Sorry, couldn't resist!)

 

[KarronR]

Thanks for the advice, we've had builders telling us to concrete over the garden next to the house to stop damp getting in, others telling us thats the worst thing to do. Some say we can treat what we have, others that all the plaster both inside and out needs to be replaced...etc etc.

Damp is a huge problem here during the winter as we get so much rain, in the summer its lovely!
Houses are built here by poring concrete into a wooden shell, the wood they then remove afterwards. Newer houses tend to only have the main supporting structure in concrete, they then fill in the gaps with bricks.
Insulation in the 50's after the earthquake was virtually non existent so they owuld more or less just plaster and that was it.
The only damp proofing that they really do on new houses is to paint bitumen on the outside wall of the foundations to just above ground level. Most people I know have some sort of damp in their houses during the winter, but ours is excessive. I do think we have rising damp in some areas as well, but I agree condensation is probably the main problem. We don't have central heating either which is probably not helping. Hence the decision.....do we buy and do it up or move elsewhere??!!!

And we are on Kefalonia, 1 of the islands and live about 2 mins from the sea.

 

[Blagard]

Hi,

I can't see concreting over the ground will do any good.

The type of construction you describe sounds really crude and better drainage around the house may help some. i.e. when it rains keep the water run off away if possible

I did a quick search to see what I could find on your construction and basically the nearest to yours seemed to be concrete footings and walls with a DPM around the foundations and then a membrane partly up the walls. You don't have the membranes so it just a question of what remedial systems are available out there ?.

If it was me I would be thinking of "tanking" floors and walls to a height above any rising damp, maybe the whole way for the ground floor then dry lining the walls with plasterboard and insulation, and screeding the floor. By tanking I mean something like several coats of RIW or similar.

For tiled floors you could leave them as they are, but the damp air/humidy due to a lack of Floor DPM probably excabates the condensation problems.

Bottom line - Whats will it cost and will it be worth doing.

PS it would take me several weeks to survey and write up if I came to look at it

 

[KarronR]

Sounds like a hell of a lot of work and mess. As per most greek houses the floors are all either tiles or marble. Main problem we have is that developers like to buy up land like this and build apartment blocks. But there are a few people now starting to buy houses like these as there are not many left in the town.

And as far as the survey goes, you need to wait for the summer......weather is terrible now!!

Thanks for all the advice

 

[Nige F]

You are a brave soul for posting on this Site! - While it does sound as if your dampness is mainly condensation related,
The battle with Condensation is fairly straightforward.
)

So was the Greco -Trojan War