Daft installation then.

It nearly came to pass a few years ago that all gaines were going to have to be accessible for regular cleaning and an obligation for maintenance contracts, based around a (now) discreditted study of Legionnaires disease paid for by the lobbyists, thankfully wiser heads prevailed.

A neighbour that I had a relationship with was renting from a HLM type organisation (cant recall the correct term) the kitchen cupboards fell off the wall from a supposed roof leak, she had to claim on her insurance, the contractors allegedly repaired the leak then replaced the kitchen cieling and cloisons & replaced the kitchen units, all this before we got together.

She complained that the VMC was not removing cooking smells and that were now present in the bedrooms and that the kitchen cieling was again showing signs of mould, they sent out an engineer who said everything was OK, when I looked there was an open VMC sortie to the heavens just like on Johnnies picture, it was clear what had caused the original damage (the open vent stub) and it had not been detected or repaired nor were any other roof repairs evident, the rain was still coming in and all the insulation sopping wet, only a question of time before the kitchen ceiling and cloison failed again. They had not even replaced the VMC exit gaine and it was just putting the smells into the roofspace,

She explained to the social housing group the problem, another engineer was sent out who patronised her and said that everything was correct and as it should be.

She later moved to another area and the new tenants had exactly the same sinistre during the winter rains.

Precisely what I meant, any gaine should go horizontal as soon as they clear the plafond, any exit gaine from the VMC should if possible also go horizontal before connecting to the roof cowl, one of mine is tucked right up under the tole bacaciér but I have used a domed cowl which fits directly down onto the spigot of the caisson.

There was no cowl as such on the rented property or it had blown away if there was one, you could look up through the spigot vertically to the sky.

No excuse for the insurers technician, the repairers or the maintenance technician for not seeing the disconnected gaine and the daylight pouring through, none of them had even gone up into the roof space.

I viewed a house some years ago where the VMC had set fire to the roof, I wouldn't risk it. We have a Qlima de-humidifier that I can leave on for a couple of hours a day and which drains to the outside but since all the house is now double glazed the problem has all but disappeared.

I know that doesn't help as you are no doubt waiting to board your ferry but for future consideration.