Why is my house so damp when it never used to be this bad?

[CormorantStrikesBack]

I5s an old Victorian house. I know that damp is generally down a lack of heating and ventilation.

so I have the heating at 19degrees. I admit I’m not great at this time of year about having windows open but I manage ten minutes in the morning in our bedroom before going to work, longer if I’m wfh. But I’ve never been great with the windows so no different to normal.

The house is noticeably damper this year than previously. There are damp patches on all external walls, condensation on the walls. We are getting mould.

i am wiping the walls every day. We use a window vac on the windows every morning. I have a 12ltr Meaco dehumidifier running constantly. So it’s been going in my bedroom with the door shut most of the day, I started it at 8am, went up at 6pm and it was full so had stopped. Started it again and the reading is still 80%. Room feels damp. It never used to be this bad.

i move the dehumidifier downstairs overnight. I probably could do with one in every room but can’t afford the electricity! I’ve ordered some of those non plug in ones, not sure how useful they are.

do I need to get anything structural checked with the house? I asked dh and he just said well it’s cold outside so we’ll have more condensation. But I swear a few years ago it wasn’t like this even when cold.

Do I turn the heating up to 20?

19 is nowhere near warm enough to prevent damp, I'd have thought.

Needs to be around 24 or windows open.

That sounds fairly drastic so I'd probably invest in a surveyor to come and look and assess areas where you may have a leak from roof / brickwork etc.

The damage the damp could cause would probably be more expensive than sorting it relatively early

It’s been so sunny here today, and the windows have been open most of the day, front and back, to totally change the air.

you have to find a way to leave the windows open when you are out all day.

how do you dry clothes? Cos closed windows and clothes on radiators is a recipe for mould

What? Who has their heating at 24? I’d swelter.

Our house is at 19 and bone dry. I think you have a structural issue OP. Is there anything visibly wrong with the outside of the house? Any missing mortar, damaged brickwork, broken gutters etc?

Damp surveys are often done for free by companies hoping to attract your business. That might be a good place to start.

Ok, will turn the heating up. Clothes drying is a combination of drying outside where possible, tumbling drying and some drying on a line in the utility room with the door closed and the dehumidifier in laundry mode underneath it. Which I know isn’t great, but I’ve always done it.

will talk to dh about a surveyor, I think he’s in denial

I've had the same problem recently. This has been the worst year for damp and mould since we moved here nine years ago. I think you're doing the right thing re ventilation, heating and dehumidifier. They're supposed to be cheep to run, aren't they? I make sure to open the windows but then DH shuts them again!

It’s partly because it’s rained so much this year. Our house is showing much more damp than I’ve seen for years.

a few years ago we had the front of our house, which gets prevailing weather, painted with a silicone solution that waterproofed it. We needed to do it again this year. Ours is an old, stone cottage.

24! I don't think i have ever set my thermostat to 24 and I've never had damp like you're talking about. We have a similar set up, down to the window vac and dehumidifier, neither was necessary in our last place but that was draughty.

@CormorantStrikesBack try opening all windows for an hour at least every day and turn your heating up. You need to let all the condensation out; especially in the bedrooms and bathrooms. infact, bathrooms should be aired properly after every shower or bath. it is false economy to turn heating down if it leads to a massive problem in the house!

Windows open for ten minutes is not enough. Do you have trickle vents? If so get them all open all day. If not at least one window front and back in a locked open position all day.

Have you had new windows or closed trickle vents? I've had. New front door replacing a very old door that you could see daylight round and one having to make sure windows open where possible to get some air in

23/24 with windows opened for a few hours in the morning.

Because it rained the entire summer and all the old houses did not have time to dry out.

I keep seeing this exact same problem being raised.

God knows how much it would cost to keep me old victorian house at 24 degrees. Even for a short time.

Our house is also much damper than usual this year. I’m putting it down to months and months of endless rain. Our dehumidifier is on every day.
I would check your guttering. If it’s blocked with leaves or moss then it could be overflowing onto the walls and causing damp.

I’ll turn it up to 20/21 and see if that helps. We don’t have trickle vents but can keep my bedroom window open securely while out so guess I could, it just makes the house so cold! Plus I then couldn’t use the dehumidifier in there while the window is open. I had the window open for a couple of hours one day last week and then shut it and turned the dehumidifier on and it was 75% damp so still not great. I can normally get it down to 57% by evening with the dehumidifier going all day.

We have a new build house in good condition and only 20 years old, we are running dehumidifiers in different rooms upstairs and down every night and it is always half full in the morning. The summer was very wet and there has been so much rain this autumn, I think PP is correct that with an old house it will have soaked it up like a sponge.

It couldn’t hurt to get a check over by a surveyor or builder, we had badly blocked gutters when we moved here and there could be something simple that would improve things.

Despite the dehumidifiers being half full nightly we have no visible damp or condensation and our heating is only on at 19° too.

We do have windows on ventilate as well even in winter.

I would have a survey to check.

I live in a victorian terrace (circa 1850-1875) and we've also had similar issues this year. I think @KievLoverTwo has it, this summer was particularly humid, even at the hotter temperatures- September was hot but also damp here so the houses haven't dried out as they usually would over the summer months, and there has been more humidity indoors and out. Our dehumidifier is also on non stop, and our heating set to 21.

Do not under any circumstances employ a ‘damp surveyor’. Employ a qualified building surveyor. Damp surveyors aren’t qualified surveyors 99% of the time, just dodgy salesmen.

Most damp is either caused by water ingress from leaking pipes or condensation from too much moisture generated internally from people and living. Do you have internal shower rooms or similar? What kind of windows do you have? I am a big fan or either Mvhr units or continuous extract fans. You can pull in stale air from multiple points slowly and it will draw in air around leaky windows etc

I also live in an old property but don't ever run a dehumidifier

Open the windows every morning to air the house - even in winter.

dry air is cheaper to heat than damp air so dampness means heating is more expensive