We've got an insulated house, heat it properly, ventilate it, but still see humidity levels of 70%+ in bed rooms. How to fix that?
We've got an insulated house, heat it properly, ventilate it, but still see humidity levels of 70%+ in bed rooms. How to fix that?
We built a house 7 years ago and it's insulated and has double glazing. I've installed Home Assistant with temp sensors in the bed rooms and seeing 70%+ humidity levels. Temperature is always above 16c
We ventilate it, but still it's 70% in the bedrooms. WHO recommends 40-60%, so we're a bit worried.
Living room is around 55% during the day when we have the heat pump set at 21c.
As it's pretty humid outside I think it's almost impossible to get it lower, but are there any other tips? I don't want to run dehumidifiers. Would an HRV like system help?
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So your house is insulated and warm, and presumably pretty sealed. I think you should be considering sources of water vapour.
Some common sources:
- Shower
- Drying clothes inside
- Cooking
If you have a separate shower (rather than shower over bath) you can get a shower dome which significantly reduces steam leaking outside the shower. I don't much like using a shower with one but they are effective. You can also get a more powerful extractor fan, though even the super powerful ones don't seem to be that powerful (I want one that sucks your clothes off).
If you dry clothes inside, try not to. If you have a dryer that isn't a condenser dryer, try to vent it outside or at least open the window. Probably try to use it less though using it less and not drying clothes inside don't make for many options in the winter.
For cooking, make sure you have a rangehood to catch the steam from any boiling pots. And make sure it's externally vented. I have lived in placed with rangehoods that just push the air back into the room (I'm not sure of the point...) but I'd think with a house that new it wouldn't be an issue.
You might have other ideas about sources of water. Gas heaters can be one but it sounds like you heat with a heat pump.
An HRV/DVS can help but I'm not sure it's as effective in a newer house.
You also mention the living room is 55% in the day when heated to 21c, what temperature are the bedrooms when they are 70%? Colder air can hold less water, and so the relative humidity is higher with the same amount of water in the air.
Thanks Dave, much appreciated! Yes, I guess it's from internal sources, like shower, drying clothes and cooking. Will try to decrease that, but as you said, drying clothes outside is not really an option in winter.
So, right now, living room is [email protected]%. Bed room 1 is [email protected], bed room 2 is [email protected]%, bed room 3 is [email protected]% We've got doors open so it should stabilize a bit more. I understand that higher temps means lower RH, but I don't want to heat bed rooms to 21c. There are panel heaters in each bed room, which are set at 16c during the night, and at 19c at the end of afternoon until 6pm.
Garage is [email protected]; which is not insulated & not heated.
Think as a gap stop I'll get a dehumidifier, especially for the colder winter months.
Other than the garage, those temperatures/humidities all have a similar amount of moisture in the air, the difference comes from the temperature of the room. See this calculator I googled up: https://www.omnicalculator.com/physics/absolute-humidity
So the warm air has X amount of water in it, and when it goes to the cold room it still has the same amount of water, but because cold air can hold less water the relative humidity goes up. So I don't think there's anything special about the bedrooms.
The dehumidifier is probably a good idea, but before you go and buy one, check if your heat pump has a "dry" setting.
Thanks Dave again for the insights!
Our heat pump has a dry setting, but it must be set 2c lower than ambient temperature. So it's getting quite cold. I was hoping / assuming that a dehumidifier wouldn't cool that much.
But perhaps worth giving it a try for an hour or so.
Ah interesting, I've never read the instructions just hit "Dry"!
Don't forget to warm the room back up before checking the humidity or the cooler air might make you think it hasn't made a difference :).
On another note, I've always wanted to try home assistant but never got around to actually getting any equipment. What sensors did you get?
Don’t forget to warm the room back up before checking the humidity or the cooler air might make you think it hasn’t made a difference :).
Yes good point! Doing a test now, set to dry, will check how it goes.
On another note, I’ve always wanted to try home assistant but never got around to actually getting any equipment. What sensors did you get?
First of all, it can be a rabbit hole. Secondly, it's awesome. I've set it up on a Raspberry Pi, and set up a Zigbee mesh with the Home Assistant SkyConnect dongle from here. I bought some Sonoff temp sensors, and Sonoff Smart Sockets to increase the Zigbee network range. I've also bought some Smart Sonoff Bulbs at Aliexpress but I'm not very happy with them as they caused some Zigbee network issues. Seems to have resolved it by itself somehow.
Our heat pump is not a smart one, so I'm using a Broadlink RM3 Mini to control my heat pump. Works like a charm. That way I would also be able to set it to dry and heat on intervals of e.g. 1 hour during the night.
Any other questions just ask.
Oh boy, that's cheaper than I was expecting startup costs to be... I am oh so tempted now!
With HomeAssistant, as I understand it, it needs the full Pi? I have a bunch of services running on my RPi 4 and so when I've looked at HomeAssistant I haven't been able to install this without touching the other stuff on there. I think they have a docker container version but it has a lot less features.
I have for a while been intending to uprade my stuff to something that can handle photos/videos better, but haven't got around to it. I might need to wait until I do that, then I'll have a spare Pi to use for HA.
I'm guessing an RPi 1B won't handle it. It's running Pi hole at the moment, but I think this is about the only thing it's capable of.
Do you have any old x86 computers lying around?. I am running a NAS serving a dozen docker containers and a VM on an ancient 4th gen intel cpu. I never got into the home assistant stuff but maybe I'll also give it a go! I use PhotoView to share photos with family through CloudFlare zero trust tunnel.
Computers outnumber adults in our house by quite a bit, depending on what you count. There's one in particular that I think would make a good server, but it's a laptop and I can't find the power cord!
Other than that, the Raspberry Pi 4 handles many services just fine, it's just photo/video that are pretty slow (and gets worse the more you use it, so probably thermal throttling - it doesn't have a fan). But it turns out you can run Home Assistant in a docker container and still use the addons by connecting them in other docker containers, so I will give this a go once I get a chance.
I have an unused Pi4 4GB model lying around, I might try run HomeAssistant on it. Sounds like a fun project.
Do it! You might also consider this list of self-hostable projects: https://github.com/awesome-selfhosted/awesome-selfhosted
With HomeAssistant, as I understand it, it needs the full Pi? I have a bunch of services running on my RPi 4 and so when I’ve looked at HomeAssistant I haven’t been able to install this without touching the other stuff on there. I think they have a docker container version but it has a lot less features.
I'm running it dockerized as well as I'm using it for other stuff as well, like PiHole, media server, etc. No problems at all.
Some features are missing, like editing config files in the browser. Major gap is that add-ons are not supported. Add-ons are essentially 3rd party apps, like DuckDNS, Frigate or MQTT. It's mostly annoying because the documentation assumes you run the HASS version. But it's no big deal, you can set up those apps yourself. I'm running Frigate and MQTT dockerized and connected to HA without issues.
For docker resources, check out https://www.linuxserver.io/. I used to install apps like NZBGet, Radarr, etc. all directly, which was very annoying as each app uses a different install script. With the docker compose files from linuxserver it was a breeze. I only run PiHole directly, as I saw some issues with the Docker version, the rest is all dockerized.
Ah thanks! I think I decided not to continue when I saw it didn't support add-ons as I thought that would make it pointless, but it sounds like you can run them in their own docker container and connect them. I've used linuxserver.io docker containers before. Thanks for the tips!
Hey hey. Yeah I’ve been toying with the idea of going to a dockerised setup for HA. I run it as a VM on one of my servers and that’s been rock solid along with add ons and the like.
My moto with this whole HA thing was to always do it as cheaply as I can. That has meant a fair amount of building circuits and such myself which is quite a bit of fun.
Also check out ESPHome. It’s great and integrates into HA very well.
Yeah I run HA as a docker container on unRaid, alongside ESPhome. It works fine - have never had a situation where I wished I was running the OS/VM version of it instead.
TBH though, I kinda hate HA; its really kludgy for anything that I've wanted to do, and a lot of the presence based stuff seems super flakey. I'm constantly getting notifications about Frigate events when it knows im in my home area & they're supposed to be silenced.
I have for a while been intending to uprade my stuff to something that can handle photos/videos better, but haven’t got around to it. I might need to wait until I do that, then I’ll have a spare Pi to use for HA.
I’m guessing an RPi 1B won’t handle it. It’s running Pi hole at the moment, but I think this is about the only thing it’s capable of.
Not sure, HA itself is not very demanding. Most demanding thing I'm running are NZB's (extracting / par check), Photoview (to index the photos on my NAS), and Frigate (web cams with motion detection). I've set CPU limits for each docker container to ensure it's not overloaded, installed a fan, and now it seems to perform okay.
The RPi model B was the first iteration of Pi's available (they released two at the same time, A and B). It has 512MB RAM and a 700MHz CPU. It is painfully underpowered. I doubt the stuff you're talking about would be able to run on it. But since you mentioned running HA dockerised alongside other services and having it work OK, I think I'll do that method on my RPi4.
Yeah, the RPI4 is pretty good. I had to install a fan as it got hot pretty quickly and at 85c it will throttle.
Main issues I had were with photo management solutions, which would completely knock out the Pi. Photoview and Pigallery2 are ones that are working well on my RPI4. I still have CPU limits on those docker instances.
Also, had to tweak a bit with the settings for Frigate. They recommend a Coral for motion detection, but they are very hard /impossible to get or very expensive. I run 2 cameras with CPU motion detection and it works well. Load of my PI is between 1 and 2 so that's fine for a quad core CPU.
I'm seeing some odd behaviour. I've set the heat pump to dry twice, for about 30 minutes. Both temp and RH drop, which is good. However, as soon as I turn it back to heat, the RH jumps up about 6% within 5-10 minutes. The sensor is a couple of meters away from the heat pump, so that's odd.
Also outside it's 14.5c @ 72% so I have no idea how to get it 16c and below 60%. That seems only possible if I shut all windows and have dehumidifiers running 24/7. I see articles where they recommend 30-50% in winter, how the heck is that possible when it's damp outside.
I’m seeing some odd behaviour. I’ve set the heat pump to dry twice, for about 30 minutes. Both temp and RH drop, which is good. However, as soon as I turn it back to heat, the RH jumps up about 6% within 5-10 minutes. The sensor is a couple of meters away from the heat pump, so that’s odd.
Could this be as simple as the heat pump is blowing out dry air, but hasn't turned over much air total. Then when you stop it, the dry air mixes with other air around the house and the humidity comes back up?
Also outside it’s 14.5c @ 72% so I have no idea how to get it 16c and below 60%. That seems only possible if I shut all windows and have dehumidifiers running 24/7. I see articles where they recommend 30-50% in winter, how the heck is that possible when it’s damp outside.
I dunno man. I tend to think I live in a warm, dry house. We only heat rooms we are using but otherwise we don't hesitate to turn on a heat pump. We have never had an issue with mould or dampness. But I just have this feeling when I get some sensors they are gonna say 70% like yours and I'm gonna have to go down a rabbit hole trying to work out why!
We do have a DVS, but ours is an older home. I think they help more with heat recovery (all they do is pump air from your ceiling cavity into your house - which is often warmer because heat rises). They do slightly pressurise the house because they are pumping air in, which can help stop outside air getting in cracks, but I can't imagine a fairly new house like yours would have the same issue with that as our 50's house. Maybe throw a sensor in the ceiling and see if the air is warm and dry up there?
I think your assessment is likely correct, 30 minutes isn't long for a dehumidifier to do much work, and unless there's a unit in each room, or its central then for the total volume of air it won't have pulled much more than was in the general area its located.
Yeah we assumed our house wouldn't have moisture issues being so new. But... If I hadn't measured I wouldn't know as we don't have massive moisture issues. Main issue is condensation on the window frames as they are not thermally broken. Well it is what it is.
I've ordered a 10L dehumidifier, we'll ventilate more, and let's see how it goes then.
It's not so easy to get onto the ceiling but it's indeed worthwhile.
Good luck!
It’s not so easy to get onto the ceiling but it’s indeed worthwhile.
You don't have a man-hole in the ceiling in a wardrobe/laundry or other out of the way place where you can just poke a sensor up into the ceiling?
Ah interesting, I’ve never read the instructions just hit “Dry”!
Yeah, I noticed it didn't do anything when set to e.g. 22c when it was already 22c there. Then I read the manual, which is a bit cryptical:
When the room temperature is higher than the temperature setting: The device will dehumidify the room, reducing the room temperature to the preset level. When the room temperature is lower than the temperature setting: Dehumidifying will be performed at the temperature setting slightly lower than the current room temperature, regardless of the temperature setting. The function will stop (the indoor unit will stop emitting air) as soon as the room temperature becomes lower than the setting temperature.
Notice the bold part. First it says, if the temp setting is higher/same as ambient, it will perform slightly below ambient. However, next sentence it says it stops when temp setting is higher/same as ambient?
I have to set it e.g. 2c lower than ambient, otherwise it just doesn't do anything
Yes I noticed it contradicted itself. I think that was probably referring to the earlier part, that you start it when the temperature is high then it keeps going until it reaches the set temperature.
I am going to go and play with ours now, we haven't really used that setting, but I have no idea what the humidity is in the house. I've just in the past in a different house had to work out how to reduce dampness and mould.
Yes I noticed it contradicted itself. I think that was probably referring to the earlier part, that you start it when the temperature is high then it keeps going until it reaches the set temperature.
Yes, guess you're right.
I've got a cheap weather station from Aliexpress which also has a humidity sensor, that could be a temporary solution for you if you don't go for the HA route.
Nah, that takes the fun out of it. Given how cheap the parts are I'm going to have a play at getting HA set up when I get a chance.
Dry setting while you're out of the house during the day?
Tried dry during the night, didn't do anything for humidity.
A dehumidifier will actually add a bit of heat.
So many folks overlook the Dry setting on a heatpump :)
Though as I learnt from this thread, it's so much more complicated than just turning it on!
You could probably solve most of this problem by installing an ERV but those are fairly expensive.