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frosty windows

i have a newly built home, why am i getting frost on the inside of my windows?

jaros bros.
Re: frosty windows

There could be several culprits leading to your frosty windows, but first you have to realize what cause moisture to condense onto any surface. Whenever you have a cold surface and lots of hot moist air, you will have condensation. Most people want to blame the windows and not without reason. Perhaps the argon has leaked out or maybe the seals are shot leading to the inside pane being exceptionally cold and leading to more build up than normal. On the other hand, maybe you have excessive moisture in your house, even in a particular room that is leading to the frost. Is your house new and built tight? Does it have an air exchanger? Is the window new or old? Has the seal failed? Can you take a humidity reading in your house to determine if you have high humity? All good leads to check out.

Josh Jaros (Jaros Bros. Construction)

Re: frosty windows

I would first ask what type of windows you have, vinyl,aluminum,wood,clad? What type of glass package do you have? Single pain, insulated (how thick, 3/8",1/2",3/4" or 1"). Does the glass,if insulated, have argon gas in them? Where is the frost on the window,at the edge of the trim, the parting bead or somewhere else on the window? Is it really frost or condensation?

Calcats ;)

Re: frosty windows
hawk4611 wrote:

i have a newly built home, why am i getting frost on the inside of my windows?

One key point here ... you have a newly built home which tends to be more "tight" regarding air sealing.
Basically because of the home being "tighter" the inside realtive humidity level ( RH ) tends to increase.
As Josh mentioned .... if the RH is too high during cold outside temperatures condensation will form on the windows. This is one of the first places that will indicate this issue of the RH being too high .... probably 45 - 60 %
Bottom line ... the lower the outside temperature the lower the inside RH level.

Here's a couple of examples .....

this first one is from a newer constructed space with newer double pane windows .... outside temperature around 33 below zero ( 57 below with howling windchill )

the humidity ( RH ) in this case was around 50% wich is way too high and should be down around 30 % RH.
Combine that with a slight draft from a howling sub-zero wind and you have frost.

The next one shows an old 3 / single pane slider with aluminum frames .... same weather conditions.

Difference here the RH is only 32% ... no condensation .

Re: frosty windows

Love the quote Marcus and Canuk your pictures are always helpful.
What does the bulder say and do your neigbors have the same issue, if the same bulder.

How about a dehumidifier? In my house I have to use just the opposite in the winters up here in Buffalo. John

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