Humidity Level in House

[SW20 MR2]

In the summer, I had a dehumidifier running in the basement 24/7 for our brand new home, but I turned it off a few weeks ago since it's no longer humid/hot. When I sleep, I feel that my throat is always really dry. The hygrometer reads 31% or so humidity (temperature is 22*). Could the humidity level be causing this? If it is, is it really a no-no to turn on my furnace humidifier? I know some people suggest not to run a humidifier during the first year, but I want to be comfortable.

[The PDI Guy]

In the summer, I had a dehumidifier running in the basement 24/7 for our brand new home, but I turned it off a few weeks ago since it's no longer humid/hot. When I sleep, I feel that my throat is always really dry. The hygrometer reads 31% or so humidity (temperature is 22*). Could the humidity level be causing this? If it is, is it really a no-no to turn on my furnace humidifier? I know some people suggest not to run a humidifier during the first year, but I want to be comfortable.

Tarion suggests an acceptable humidity rate of 30-50% so you do have some room to work with. If your home feels to dry you could use you humidifier as long as you watch your humidity levels and keep them uder the 50% mark.

[Bullseye]

It's nearly impossible to imagine a new home that has too low humidity, unless the house is very drafty or the windows are open all the time. Most new homes have the opposite problem, far too much humidity, due to materials drying and tight construction.

I'd guess the hygrometer is not working properly, which is pretty common with cheaper ones.

One possibility...your throat could be dry from all the chemicals off-gassing from the new building materials (and presumably furniture). Not really a pleasant thought, but you can blame the Ontario government for bowing to builder pressure opposed to making HRV's mandatory in all new homes.

Some related reading;

http://www.thestar.com/article/278825

'New homes and recently renovated ones include features that keep warm air in and drafts out. That's good.

What's not so good is the other stuff that tight construction holds in: airborne contaminants and moisture. If your windows sweat a lot, it indicates inadequate ventilation. There's too much water in the air, and probably too many off-gassed contaminants, too.

My favourite way of solving the water problem automatically leads to much better indoor air quality.

All of this is why your best solution to window condensation is a heat recovery ventilator, or HRV. It's a ventilation appliance that draws fresh outdoor air into your home, expels moist, stale indoor air outside, while also retaining about 80 per cent of the heat energy invested in the old air.

Outdoor wintertime air becomes bone dry when it's brought inside and heated up. This is why HRVs are so effective at reducing sweaty windows. They lower indoor humidity levels like nothing else can. '

[Pete_Coach]

Here is some CMHC info on humidity and other related information.
http://www.cmhc-schl.gc.ca/en/co/maho/yohoyohe/momo/momo_002.cfm
http://www.cmhc-schl.gc.ca/en/co/co_001.cfm

Also, here is a chart on what the levels should be
http://joneakes.com/cgi-bin/getdetailscals.cgi?id=1626

[nopn]

why does indoor humidity level decrease as outside air temperature decrease ?

should it be the other way ?

[Diamondog]

Give me a break turn on your humidifier humidity range should be at around 50% (low end of normal range)

[Pete_Coach]

why does indoor humidity level decrease as outside air temperature decrease ? should it be the other way ?

Cold air is much dryer than warm air. Dry air comes in from outside and mixes with your indoor air.
Because you do not want condensation to occur and then freeze on your windows or any cold surfaces. Allergies can develop or flourish. Mold, mildew can form in these condition as well as structural damage to wood can occur if the remaining moisture in the wood freezes. Insulation could become damp and reducing it's effectiveness.

Give me a break turn on your humidifier humidity range should be at around 50% (low end of normal range)
A profound statement. Your impeccable sources are?

[romsan04]

why does indoor humidity level decrease as outside air temperature decrease ?

should it be the other way ?

I would say, because of cold air. Less humid air gets into house thus decreasing humidity inside.

Found some interesting info:
http://irc.nrc-cnrc.gc.ca/pubs/cbd/cbd231_e.html

The greatest proportion of moisture is removed from houses by the replacement of inside air with outside air. When cold outside air is introduced into a house and heated, its relative humidity is reduced, and it can absorb additional moisture. (Outside air at -30°C and 100% RH when heated to 20°C, for example, will have an RH of less than 2%.) The constant replacement of inside air with outside air carries away moisture; the higher the air replacement rate, the lower the humidity level.

[sunnybono]

To the OP listen to Pete_coach and CSK'sMom. They bang on when it comes to this issue. It has been discussed at length and if you read up their sources you will definitely get a better grip on the situation!!!!!

sk

[nelsonmp5]

Just a side note. If you have hardwood flooring I'd recommend to keep it at the high end of the 30-50% range. Otherwise you may see gapping. The hardwood will shrink with lower relative humidity of the air, unless its picking up moisture from another source like the subfloor.

[Matrix_dot_ca]

I bought a hygrometer at Wallymart that looks like this >
http://www.weatherconnect.com/scripts/imageloader.asp?img=00613_p.gif&type=p

The humidity reading at the upper floor is 39-42% humidity level as "low". But on the main floor 38-43% humidity level as "ok". So same percentage but giving different humidity level?:confused:

So is the upper floor "dry"?

[Green_Star]

What kind of problems we may face with hi and low humidity? in my home i have around 27%-30%, i know it is low. And one other friend has around %65. His windows always looks like it is raining outside(because of soooo much water formed on windows).

[The_Professor]

I bought a hygrometer at Wallymart that looks like this >
http://www.weatherconnect.com/scripts/imageloader.asp?img=00613_p.gif&type=p



Do you remember what you paid for that? I need to get a humidity meter and that one looks okay.

[jm1]

What kind of problems we may face with hi and low humidity? in my home i have around 27%-30%, i know it is low. And one other friend has around %65. His windows always looks like it is raining outside(because of soooo much water formed on windows).

Read the links above. They address your questions exactly.

[handles]

I live in a brand new 1 month old house, and I keep the temperature at 22. We also have this low humidity problem around 30 percent. It seems very dry all the time especially in the morning after waking up.
Speaking with 3 neighbors who also have hygrometers (all different ones) and their humidity is the same. There are no drafts and the windows stay closed.

[Green_Star]

Read the links above. They address your questions exactly.

Yup, I read those, actually I want to ask about health wise.

[gomyone]

I live in a brand new 1 month old house, and I keep the temperature at 22. We also have this low humidity problem around 30 percent. It seems very dry all the time especially in the morning after waking up.
Speaking with 3 neighbors who also have hygrometers (all different ones) and their humidity is the same. There are no drafts and the windows stay closed.

..from what I've been reading - new houses are supposed to have high humidity readings because they are built tightly and trap warm moist air. This is the reason why condensation generally forms on windows.

However like the above poster, I have 1 month old house and bought a hygrometer to check humidity levels after seeing condensation form on my windows. Trouble is, the hygrometer (which is digital) is usually at "comfort zones" (ie., temp of 21 and humidity at around 40%). Sometimes the humidity level is a little lower (in the mid 30s). So why the condensation on the windows?

[romsan04]

..from what I've been reading - new houses are supposed to have high humidity readings because they are built tightly and trap warm moist air. This is the reason why condensation generally forms on windows.

However like the above poster, I have 1 month old house and bought a hygrometer to check humidity levels after seeing condensation form on my windows. Trouble is, the hygrometer (which is digital) is usually at "comfort zones" (ie., temp of 21 and humidity at around 40%). Sometimes the humidity level is a little lower (in the mid 30s). So why the condensation on the windows?

Because it's too cold outside and too warm inside. Even if your house will have 10% humidity you will still get condensation.

[sonic]

Do you remember what you paid for that? I need to get a humidity meter and that one looks okay.

Yes..i need to buy one as well,,,was it expensive? :confused:

[Matrix_dot_ca]

Yes..i need to buy one as well,,,was it expensive? :confused:


It is cheap. I paid $7 but thats in Walmart US. I bought it the last time I cross borders. Not sure if it is available in Walmart Canada.

[Whiplash7828]

I noticed last night that I have a "puddle" of water on my north facing window sills (top floor only). YIKES! Can condensation actually drip down and leave a puddle on the window sill???

Will applying the plastic film on these windows correct the problem?

[Gidget]

I noticed last night that I have a "puddle" of water on my north facing window sills (top floor only). YIKES! Can condensation actually drip down and leave a puddle on the window sill???

Will applying the plastic film on these windows correct the problem?

Yes condensation can drip and leave a puddle. Open your drapes as much as you can to let the air circulate and leave your furnace fan to on instead of auto.

[Whiplash7828]

Yes condensation can drip and leave a puddle. Open your drapes as much as you can to let the air circulate and leave your furnace fan to on instead of auto.

Thanks. Our home is heated through electric baseboards only.

I noticed a few more elements tonight:
- The room is currently 23 degrees and 26% humidity (so excessive humidity does not seem to be the culprit) and there is just a bit of humidity/water on the window sill (seems likes its coming from under the sliding tracks).
- The windows are double sliding windows (4 glasses)...the outside glass is the one with condensation and frost....The inside glass is dry on both sides.... {confused}

Questions:
1- Should I address this (condensation on outside glass) the same as any other condensation problem?
2- I have two identical windows on the ground floor (same side of the building) that have no condensation....and my patio door is fine.....but why the two windows on the 2nd floor?
3- What happens to water trapped between the glass (the sliding tracks)? Does that drain somewhere? or does it just seep indoors?

thanks.

[Dustbunny]

Usually there are usually weeping holes in those tracks which should allow any water to move to the outside sill. Check to see if they are blocked (often they get full of dust).

Meanwhile, if that isn't the issue, then for some reason maybe that room is holding more humidity than the others or the windows aren't holding their seal like the others are.