Oh fuck, damp patches on walls!

[BasinHaircut]

Bought this house in April so it's been relatively dry so far. Today has been really heavy rain all day and we have come home today to the entire front wall in the lounge damp up to about 40-50cm.

The house is 1930s with a square bay. There also appears to be a bit of damp along the side wall (we are end of terrace) but can't see properly because of radiator/under stairs cupboard/kitchen units.

We have just put a deposit down on getting the house re-rendered (literally today). When the guy came to quote a couple of weeks ago he said the current bottom bit was too high and breaching the DPC so I'm hoping that that is the cause of the damp and would be rectified with new render. But I'm worried that we spend £6k on this and then end up needing a new DPC and having to have it done all over again.

We had a damp survey done when we bought the house which said that bit about the render (it's also in poor condition overall) but nothing indicating an actual damp problem.

The floorboards seem to be in good condition and dry and I'm thinking they might be wet and rotting if it was the DPC?

Anyone got any ideas what we should do?

TIA

Does rainwater gush over the gutters? Or lie in puddles against the house?

Is it a concrete floor?

Where does the downpipe go?

Hi piglet. No and no. Floor is floorboards. Down pipe is where our house is joined to next door.

We took the carpet up at the weekend as we are having some work done and I could smell a funny smell afterwards. Can't smell it now as I just have the smell of fresh plaster (not in damp wall) but I suppose it could have been a damp smell?

you say it is a bay. Does it have a little roof, and is it flat with bitumen or zinc? Perhaps the roof or gutter of the bay is leaking. You would have to look at it during heavy rain. Or it might be that water is entering around the window frames. Do you know if the house has cavity walls?

Water can also enter through cracks or bubbles in render, though this is usually localised to the damage.

Panic over! Spoke to the builder and the renderer today who are both confident that it's due to the plinth at the bottom of the render bridging the DPC. Render man is coming next week to remove it so it can dry out for s bit before it gets re-rendered.

Thank you