Condensation help!!

TheCyclingProgrammer

valleyboy22 wrote: »

Thought leaving Windows open would avoid the condensation because fresh air is circulating

It will, but its a balancing act between ventilation and keeping the room heated. If the room gets too cold you may find yourself having condensation problems elsewhere (on the wall) not to mention it being a waste of energy.

Keeping the windows cracked slightly overnight (if you don't have trickle vents) and closed during the day to keep the room warm is probably the best compromise. Seems to work well enough for us.

TheCyclingProgrammer

Without wanting to hi-jack OPs thread but as we do have a similar issue, can anyone recommend a good, quiet dehumidifier? Is it worth having more than one - one in a central location to reduce overall humidity in the house and one specifically for the bedroom (which is where we have the worst problem)?

Grenage

TheCyclingProgrammer wrote: »

Without wanting to hi-jack OPs thread but as we do have a similar issue, can anyone recommend a good, quiet dehumidifier? Is it worth having more than one - one in a central location to reduce overall humidity in the house and one specifically for the bedroom (which is where we have the worst problem)?

Cycling,

Our old place was very well insulated, and the other half was big on drying clothes inside, so we had a similar problem; bedrooms seemed to be the worst due to exhalation (I assume) overnight.

We placed one dehumidifier in a spare room upstairs, and if the doors were open during the day, the humidity through the house evened itself out.

northwest1965

Our house is bad for condensation. We have a mixture of windows in the house 2 new the rest are 15 years plus old.

The 2 new ones have a cm of condensation on them. The rest are dripping wet at night/morning.

I have a Karcher window vac and it is great, however given that the new windows are OK, I am inclined to now start to get the others replaced

TheCyclingProgrammer

Having now realised that as well as huge amounts of condensation in our bedroom, I've noticed we are also getting condensation in pretty much every room of the house on the windows, albeit in smaller amounts, so I've caved in and bought an EcoAir dehumidifier for the house. I also noticed condensation around the edges of our conservatory roof panels (glass), despite them being low-e (during the day they normally get condensation on the outside), although this evaporated quickly once the sun started to heat the roof up.

The thing that surprised me is that I didn't think the humidity levels in the house were too bad - not the 60/70+ levels some people with condensation problems have. I put my temperature/humidity reader in the bedroom last night and the humidity was about 59% at 19C. Is that high? Doesn't seem too bad to me. I was getting similar readings, 55-60% throughout the house.

I think we'll start off with the dehumidifier in the bedroom and try and bring the overall house levels down to below 50% if possible and then leave it on the landing in its smart/eco mode - is this the best location?

I assume that with the dehumidifier running we should stop leaving the windows open at night?

valleyboy22

Going to see how much difference is when we have our new windows fitted in the house then go From there I think.

Grenage

59% is fine - I never got mine down to 50% when I was using a dehumidifier. My average humidity was about mid 50s with it running with the thing running, and about 62-68 without (at 18C).

The difference however was lots of condensation on the windows, and no condensation on the windows.

The landing is ideal, but I don't think a spare room with the door open would have too much impact on performance.

TheCyclingProgrammer

That's the thing though, we have approx. 55-60 throughout the house yet we still have condensation. Our bedroom window is literally covered in it from top to bottom.

So it makes me wonder if the dehumidifier will make any difference. We shall see, it's quite possible my cheap humidity sensor is inaccurate.

If it hasn't made any difference after a few days I guess we can just send it back.

According to an online dew point calculator, the dew point for 59% RH at 20C is only 11C so that would indicate it is high enough to cause a problem when it's very cold outside - it dropped to nearly -1 last night.

At 40% RH the dew point is 5C.

Grenage

Yes, I guess it depends on the temperature of the windows. I would be surprised if the dehumidifier didn't make a large difference.

coffeehound

TheCyclingProgrammer wrote: »

Keeping the windows cracked slightly overnight (if you don't have trickle vents) and closed during the day to keep the room warm is probably the best compromise. Seems to work well enough for us.

I tend to ventilate my flat the other way around in cold weather, so windows and vents closed overnight, then trickle vents opened during the day. The bathroom has always-on extraction so pulls air through the flat. Hopefully that keeps more heat indoors overall by ventilating during the day when it's generally warmer outside. There is the penalty that warmer outdoor air can then hold more moisture but I think keeping the house warmer overnight trumps that.