Soldato
If placed on the landing upstairs, is it best to have it on continuous or aim for a targeted % value?
Humidity in the House....Talk to me!
- Thread starter dlockers
- Start date
Yeah the house has been fine for 100 years and continues to be. I think we cross the dew point on the skirting board on the tiled false wall/detail at the front on the second story - but I'll be vapour barrier and insulating that next year. The rest of the house feels perfectly fine; the only issue is the Govee humidistat whinging at me.
I think you're correct RE: chimney. I've actually got mine plugged at the minute, as the draught is killer. I will unplug it when the weather starts picking up again Feb/March.
I may do the Garden Room experiment....we'll see.
Caporegime
I set mine to a target value. It’s hard to beat Mother Nature, my aim is to take the humidity down a notch. Like I would aim for 55% (run it overnight) then turn it off in the day, it will rise slowly in the day and then do it again next night if rise high enough.
I don’t have it on all hours of the day, just a few weeks in the winter.
What's the "point" tho? Is going from 75 to 50 to 75 to 50 "achieving" anything?
Sorry for outrageous use of quote marks, but it seems like you're chasing numbers vs. actual outcome.
This is an interesting subject and one I've been paying close attention to in the loft as I get closer to finishing the jobs up there.
I put a few logging sensors in the loft and the humidity is getting close to 90% depending on the temperature. In the image below, the dip in humidity and rise in temperature is due to me having the loft hatch open while working.
After I'm done and close the loft hatch the humidity rises again as the temperature drops.
It certainly feels a little bit damp-ish when first in the loft.
I put a few logging sensors in the loft and the humidity is getting close to 90% depending on the temperature. In the image below, the dip in humidity and rise in temperature is due to me having the loft hatch open while working.
After I'm done and close the loft hatch the humidity rises again as the temperature drops.
It certainly feels a little bit damp-ish when first in the loft.
Caporegime
I aim for 50% in the machine but anything around 55% I’m happy to have it off.
I’ll leave it off until normally until it creeps back up to like 65%.
I feel like this is a bit con from big-dehumidifier. I don't remember my parents fretting about this nonsense nor having a billion relatively-expensive sensors dotted around
Feels like it!
Probably more to do with houses of the past being very leaky and poorly insulated, humidity just wasn't a problem with all the airflow. Now we seal every orifice and trap the moisture in.....
OK but why? It is still 65% shortly after anyway
Caporegime
Well, in my house…for example, I will set it to run at night. It will stop sometime around 3am and I go to work, it will creep up slowly in the day but not rise to like 70%, it get to about like 60-62% or so the next day. It’s that amount of time frame.
So in my situation I don’t need to have it on 24/7.
OK but why are you running it/bothering anyway? Why is reducing it to 60 for a bit of the day for it to just rise back up a priority at all?
Caporegime
I’m not at home, electricity cost more in the day, I’m not too concerned a few digits over 60%.
Soldato
I now run 3 dehumidifiers overnight on eco mode, in different areas of the house that don't have free air movement.
It's a trade off between energy lost through additional ventilation, versus just removing the moisture directly.
It's a trade off between energy lost through additional ventilation, versus just removing the moisture directly.
Soldato
I think he is asking you what your ultimate purpose is of running the dehumidifier. Were you getting mould/damp issues for example, and you're trying to control that? Or are you just chasing the number (sub 60% recommended) but seeing no consequences physically in your house?
This is an interesting subject and one I've been paying close attention to in the loft as I get closer to finishing the jobs up there.
I put a few logging sensors in the loft and the humidity is getting close to 90% depending on the temperature. In the image below, the dip in humidity and rise in temperature is due to me having the loft hatch open while working.
After I'm done and close the loft hatch the humidity rises again as the temperature drops.
It certainly feels a little bit damp-ish when first in the loft.
That looks like exactly what profile/response curve you should expect, with RH and temperature being the inverse of each other. The RH when your loft is closed up is just matching the outside which it will do if ventilated properly. If you notice damp/condensation in there then you need more ventilation.
Designed that way on purpose I think. See my earlier comments about chimneys, massive flow of fresh air required for an open coal fire/chimney to be safe. It has to draw upwards and burn safely to avoid dangerous fumes. That caused/required a high rate of airflow. It's dangerous to run an open combustion appliance with limited/no ventilation, that's why older boilers that weren't room sealed required air vents, and why if you run gas hobs/gas ovens then you still need adequate ventilation. I assume same with log burners.
Look also at subfloor voids and airbricks - cold outside damp air continually but no rot in the timbers.
'Breathable' lime plasters instead of cement/gypsum products on walls is another example.
Yes it was the materials of the day but also the whole premise was to get air movement through the whole house AND at the same time pump a load of heat in via open fires and cooking appliances.
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Soldato
I feel like this is a bit con from big-dehumidifier. I don't remember my parents fretting about this nonsense nor having a billion relatively-expensive sensors dotted around
Yeah to this day the first thing my mom does every day is all windows in house wide open. Doesn't matter how cold it is outside. Open for a good hour then closed up and house reheated.
Associate
This is something I've been keeping an eye on over the last 12 months. When I installed a hygrometer last year, the humidity in the house was around 80%. It's now around 60-70% depending on the weather (sometimes it'll dip to around 50% if it's really dry).
I'm in two minds as to whether I should buy a dehumidifier or keep doing what we are doing and making sure we get as much fresh air into the house as possible each day.
I'm in two minds as to whether I should buy a dehumidifier or keep doing what we are doing and making sure we get as much fresh air into the house as possible each day.
Caporegime
Oh I see.
I have guitars, and they should be between 40-60% thereabouts, or the wood shrinks or expand.
Soldato
Thanks, I'll aim for around 50-55, as our house is usually over 70%
I'm the same, and my office would sit around 70%, which won't help them.
Man of Honour
We used to suffer from high humidity in the house, often in the mid-high 80's% range. As it turned out this was entirely down to drying clothes on a airer. Once we got a heat pump tumble drier it hasn't been over 64% and most of the time is between 58-62%.
Soldato
It's a black art.
Sealing a house is generally not a good idea because the average family puts about four pints of water in to the air per day. This has to have a way to escape. And the complexity in the UK is that when you exhaust air, you may be drawing in replacement air that is just as damp! Exhaust too much and you actually make the house more damp. Especially, if you aren't keeping the house warm, which people tend not to do, these days. The trick of exhausting just the right amount isn't easy to manage.
Sealing a house is generally not a good idea because the average family puts about four pints of water in to the air per day. This has to have a way to escape. And the complexity in the UK is that when you exhaust air, you may be drawing in replacement air that is just as damp! Exhaust too much and you actually make the house more damp. Especially, if you aren't keeping the house warm, which people tend not to do, these days. The trick of exhausting just the right amount isn't easy to manage.