Excess moisture in the house

[reeferfulton]

lol true that .. Then add a tank by big vaulted windows like me , some days the water literally ran down the glass on the inside ... .....

[Jeff000]

Originally Posted by magikof7

I have the Radion on my tank, I am still topping off up to 2 litres a day.

I top off around 3g a day.....

Originally Posted by Starry

i run 2 portable de-humidifiers in my fish room (basement) and have to empty them both daily. still a little bit of dampnes on up stairs windows when its cold, but nothing like it was with out the de-hums. looked into HRV but basment is finished and is cost restrictive.
I also run a 180 gallon.

de-humidifiers are huge consumers of power and add heat to the house.

[Starry]

yep, keeps my basement toasty warm all winter!

[sphelps]

If your house is new-ish you should have an exhaust fan that vents outside from your furnace cold air intake. Typically it's turned on manually with a light switch under your thermostat. This will do the exact same thing as an HRV without the heat recovery. Try it as a temporary solution, you can replace the switch with a timer or humidistat or just run it manually for a while. See how much of a difference it makes to your home humidity and gas bill. You can also get a new thermostat to control it so it turns on with your furnace based on humidity levels. Ideally it should run with the furnace fan so the furnace can bring new air in at the same time.

Also check your humidifier as others have mentioned, usually they are controlled with a humidistat located in your furnace room which is a pretty stupid location when you think about it. Turning it off is probably best for now.

Air circulation is key to reduce mold growth as well so increasing your furnace fan duty cycle is a good idea and of course keeping your furnace filter clean.

[SmallFry]

Ok, so you've had quite a bit of constructive advice here, but I've been stuck in a room with no windows learning about this sort of thing for the last couple of months. I had to suffer, now I'm going to bore you with it too.

Part of your 'problem' is that you have a pretty new house.

In old houses there were enough leaks that the warm moist air would rise to the top of the building and leak out, probably not doing the fabric of the building or whatever insulation there was much good in the process. Cold, dry air would then be sucked in (through a wall cavity containing who knows what in the way of formaldehyde loaded insulation etc.) to replace what leaked out the top, this is called the stack effect. In an older home you may not even notice any condensation issues because the air leaks are ventilating it for you (and adding to your heating bill).

Newer houses are much more airtight than they used to be, so this stack effect is reduced or eliminated and all that humid air is stuck in there. Enter the HRV...
Where I live you aren't allowed to build a house without one. Unlike an exhaust fan, a HRV brings air in in balance with what it exhausts and recovers some heat from the exhaust air to warm the incoming air (which is very useful in a Manitoba winter). The HRV wins over the exhaust fan in two ways. First that it saves energy. Second, in a newer tighter home there are not (hopefully) enough leaks to allow new air to come in and replace what the exhaust fan is removing, so the house ends up at a negative pressure, and the flow through the fan and therefore its effectiveness decreases - the HRV is bringing air in as well as exhausting, so this isn't an issue.
I know an HRV isn't cheap, but you may find it paying for itself in heating costs, especially if you live in an area where hydro/gas is expensive.

As swill noted these mould issues may well manifest themselves in the upper levels of a house since that's where the moisture will be taken by the rising hot air, and also the windows since the R value of a window is pretty low compared to a well insulated wall. An upstairs bathroom is a prime candidate, which is why our HRV takes air from all the bathrooms one of which is upstairs and has a switch so it can be used instead of a bathroom fan. It copes pretty well with the 5 gallons a well that my tank pushes into the air, to the point I only really run it intermittently.

I have also seen them just attached in the cool air return duct of the forced air system (exhaust air upstream incoming air) and wired to the furnace blower so that it operates when the HRV is running.

Hope that's of some help.