wet house

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1

Originally Posted By: chorne
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Hi all,


I am stumped and would like you guys opinions:

I just got a distress call, not for an Inspection but for my opinion,

this is a new construction, finished in April. I am sorry that I
have no pictures but I will try my best to describe the situation.
The roof has ridge vent(snow covered), correct soffit vent, the
ceilings are sheetrock with poly between the rock and 20" of
loose blown in. The foundation walls are poured with poly
directly on the concrete with a 2x6 wall in front of that with
craft faced insulation(which is wet)
The underside of the roof sheathing has 1/4" of frost on the entire
roof, all of the windows which are up to date double glass
are iced up at the bottom of each window.

Could it be the poly on the concrete walls and above the sheetrock
ceilings that is causing the bad moisture problem?

I have never in 24 years seen anything quite like this and I wish
that I could help these poor people out.

The builder will not return their calls, of course

Any and all opinions will be greatly appreciated.

Thanks,

Carla

2

Originally Posted By: kpapp
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Carla,


In that 20" in of blown in insulation does it block the ventilation from the soffits into the attic not allowing the attic to breath properly?
Is there a basement in the house or is it ranch style with a crawl space or on slab? Is the bath ventilation and stove top ventilation venting outside or into the attic? What is the cause of the moisture build up in the first place? Is the house able to ventilate at all?

Ken Papp

--
_______________________________________
If you dont have time to do it right the first time, When will you have the time to go back and fix it?

3

Originally Posted By: Guest
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Hi Carla,


The poly is slow motion suicide; the kraft is wet because the water can't go anywhere. It's probably migrating up the wall to the attic , where it's condensing on the cold roof surface. A few things to check..is there recessed lighting and are the lights properly enclosed. Where do the bath, dryer, and range hoods vent. Are the people using any open flame heaters like a vent free fireplace or kerosene heater. If it's a gas stove, are they using the the range hood vent every time they use it.
A LOT of moisture is put into the air from open flame appliances
Much of the problem can probably be solved by making sure all the above details are correct. The bad practice of using poly along with another vapor barrier can't be solved as easily.
Another possible solution is get a damn big de humidifier and start running it.
One other possibility is the vapor barriers have prevented the concrete from getting rid of all its moisture and as it continues to dry it's releasing enough water to be a problem. This also applies to all the lumber.

4

Originally Posted By: tbramlett
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Hi Carla


Is there a source of heat that is getting into the attic, such as a hot water heater vented into the attic. I ran into a situation like this a couple of years ago. The underside of the decking was covered with frost. As I checked out the attic, I could feel alot of heat entering the attic through the closet where the hot water heater was. You could feel the difference when you crawled above the closet, it gave off alot of heat. This was also the attic entrance. There was no insulation above this closet. When the heat would rise, it would cause condensation when it hit the cold decking, which had turned to frost. I asked the homeowner how long the water heater had been there. I then found out that it had recently been installed, and moved from another closet to this one.


I also saw this problem not long ago, which was due to poor insulation in an area above a wood stove. There was also an attic fan (with no blanket) that allowed excess heat into the attic. The decking in this home had turned black on the bottom side. So maybe there is a source of heat entering the attic…Tom

5

Originally Posted By: rsonneson
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Carla



Is there a humidifier running in the house? How many teenage kids in house? Many times in new construction with vapor seal encapsling entire home too much moisture is generated by the family and the home just can not breath properly. There has to be some air exchange in the home to get rid of moisture build up. In new construction the wood framing has such a high moisture concentrate in it for the first 2-3 years that running a humidifier most likely is not needed.

--
Bob Sonneson
American Home Inspection Technologies

6

Originally Posted By: dvalley
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Carla,


1) Are you sure the soffit vents are not covered by insulation? The use of both inlet and outlet vents in attic and roof spaces aids in keeping the air moving and preventing the accumulation of frost or condensation on the roof sheathing in cold areas. "Dead" air pockets in the roof can normally be prevented by good distribution of inlet vents in the soffit areas. However, there is still a need for vapor retarders.
2) Did you actually see vapor retarders under the entire insulated area?
Ventilation alone, when insulation is used, does not prevent condensation problems. Retarders must be installed.
3) Bathroom vents should be terminated to the outside. These vents will deposit warm air into the attic also.

If the aforementioned areas are correct, then this house is definitely getting warm air that is entering into the attic area (cold air) somehow, in order for this to happen.

![](upload://lTmeIVEjnud3YbMjZtkt1UQnhi9.gif)

--
David Valley
MAB Member

Massachusetts Certified Home Inspections
http://www.masscertified.com

"Some cause happiness wherever they go; others, whenever they go."

7

Originally Posted By: rmeyers
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Carla,


Had an older house last week that exhibited similar extreme moisture and condensation problems. Iced windows, condensation on walls and ceilings, and frost on the underside of the roof decking. 2 story house, poorly insulated, and poorly vented attic. Built in the mid 60's. 4 degrees F. outside, house vacant and thermostat set down with temp in house below 50. Icicles hanging from the combination storm windows when I pulled up to job. (Looked like early stages of the "Ice Palace" in Dr. Zhivago!) In this case the source of the moisture was 4" of standing water in the crawl space.

As stated by Chad, double vapor barriers are generally a bad idea and usually create problems. Was the craft facing on the insulation to the warm side?

All the previous comments are potential contributing causes and several may need to be addressed in order to overcome the conditions you describe. In my experience with new homes, one of the more common problems is that the owners tend to set the humidifier too high. They believe the higher settings make it more comfortable and keeps their furniture from drying out. (Assuming there is a humidifier.)

With the apparent high moisture level in the attic, the ceiling vapor barrier is in fact ineffective or, as some have suggested, warm moist air is being introduced into the attic area.

Hard to confirm, but was a vapor barrier used under the basement floor slab? "Sweating" floor slabs are also a potential moisture source, thus the ever common basement de-humidifier.

Good luck in the search for answers!! Let us know the outcome!! ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif)

Have a GREAT Day!!! ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif)

--
Russ Meyers

8

Originally Posted By: dplummer
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Hi Carla ! Have you used your Hygrometer to check temp &RH% outside & in basement, 1st floor & attic area. This info will help in determining potential cause. A dehumidifier will help. inside RH should be between 30 & 45 %. Are there plastic or styrofoam moore vents in the attic trussess? Temp in the attic will let you know if there’s too much heat loss . Hope that helps. DOUG

9

Originally Posted By: chorne
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Hi all,


Thanks for all of the responses!

There is prop"A" vent and it is not blocked
There is ridge vent, it is covered with snow
There are 2 vaulted roof windows, the vaults in the
attic space are not insulated and these windows are
in bathrooms. Maybe there is enough heat loss there,
the vaults are approx. 2'x3'x 5'from the ceiling to the
roof.
There is no humidifier, no vents into the attic(bath etc.)
I will try to go back there with a camera

Thanks guys, Carla

10

Originally Posted By: rpalac
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Hi:


I agree with 90% of all that has been spoken about.

I try to go back to basics when analyzing situations like this.
Since it is new construction as stated. There probably is a lot of residual water in the wood and concrete among other products.
The use of a dehumidifier in the basement will remove a good bit of the moisture from this area. It might even be a solution. Probably not enough of one. More than likely the water droplets that are on the underside of the roof sheathing have migrated from as far as that saturated basement air up through the house and vented into the attic. There is a definite likely hood that if there are open vents from bathrooms and laundry into the attic that they are the culprit. (Some builders have subcontractors that do inferior work and leave the flex tubing dumping exhaust from laundry and bath areas into the attic instead of venting through to the outside....wrong!)

From being a builder and taking HVAC classes I have seen several of these situations first hand. They don't solve themselves and sometime vary according to the season.

*****Primary to this is the concept of how water travels. There is a relationship between water/moisture and temperature/heat.
In air conditioning they teach you fundamentally that you are not making the air cold....you are removing heat. Basically the temperature of air is -273 Kelvin or zero. When you add heat as we know as temperature you must add water. The heat is suspended in the form of moisture. That is why we observe these items: in the summer if it is humid the temperature can be 80 and we feel sticky, hard to breath and perspire without moving but if the humidity is low or dry we can have a temp of 92 and still be comfortable to a point. In the winter we say that it feels crisp and dry out, its because of the lack of moisture in the air.

To take this a step further in explanation.....during the summer when it is hot out side and we have the A/C on we put our hand in front of the unit and feel cool air.
That is not new air, it is just recycled by traveling past coils filled with evaporated freon that pulls the heat out of the air and as the air returns to the room it is 15 degrees cooler as it leaves the coils. As the air looses its temperature it looses its ability to hold water. This is water falling out of the air and into a condensate pan. It then drips to the outside on the heads of people walking by on the side walk below.

My lengthy explanation is to explain that the moisture that is on the insulation is formed by humid air traveling from a warm point area to a cold point area. The vapor barrier does exactly that , it blocks the moisture and temperature.

If the air in the building is saturated as it goes into the attic it will lose its moisture as it cools down.

Done...out of ink
Bob

11

Originally Posted By: chorne
This post was automatically imported from our archived forum.


Hi,


The poured foundation walls have poly on them,
then there is 2x6 walls in front of that with kraft
faced insulation.
I have never seen this and I do believe that the poly
should not be there.

??, any opinions

Thanks,
Carla

12

Originally Posted By: Guest
This post was automatically imported from our archived forum.


Hi Carla,


Either the poly or the kraft face shouldn’t be there. Its the double barrier thats causing the problem. Any moisture that does get in the cavity just can’t get out.

13

Originally Posted By: rpalac
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Hi Carla,


As Chad pointed out, you can only have one vapor barrier system. The vapor barrier should be as close to the heat area as possible.

Having craft paper is one, and the poly is the second. This does create what is called a false dew point.

Some what of a self explanatory name. It causes the moisture to condensate between the barriers because it is trapped.

That Chad guy is good......

The fact that there is insulation there is not wrong. I have my reservations about using bat type insulation against concrete. That is a personal preference though. I feel if it doesn't have at least a one inch air space between the insulation and the concrete along with a dehumidifier for the room you could get a trapped moisture situation. The concrete will always have a tendency to pull moisture. The nature of the beast.

I believe that the basement is the first place I would start to rectify the situation. And the double vapor barrier is definitely a smoking gun pointing toward a problem.

(Need a canoe?)

Bob



Bob

14

Originally Posted By: gbeaumont
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Hi to all,


I'm sorry to be disagreeing but basement walls is an exeption to the One vapor barrier rule. you need to use 2 one against the basement wall (typicaly poly) and one on the warm side of the wall (typicaly Kraft face but could also be poly).

![](upload://hA0d7RzP1rPXJdH3LIcL1Cn3B0R.gif)

Regards

Gerry

--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466

Inspection Depot Education
gbeaumont@inspectiondepot.com

"Education is a journey, not a destination"

15

Originally Posted By: Guest
This post was automatically imported from our archived forum.


Yep Gerry, I’ve seen that diagram before. If you install it like that, no matter what, the interior of the wall will get wet and stay wet. I’ll see if I can find the article that explains this better than I can… might take me a day or two it’s in a real magazine.

16

Originally Posted By: rmagee
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Carla:


I live in Canada (-30 C with windchill of -45C here today) where all houses are supposed to be well insulated and have air-tight poly air barriers.

Any home built that air tight has to have a heat exchanger installed. That device will change all the air in the home for fresh outside air a number of times per day. Because outside air that is below freezing temperatures holds little or no moisture it dehumidifies the home as well. The heat exchanger recovers the heat from the air it is expelling to warm the outside air it is bringing in resulting in a draft free ventilation system. In a perfect installation every room in the structure should have permanent ventilation installed.

If a tight home is left without the heat exchanger running for any significant period of time the exact conditions you describe occur.

All new homes in my area require this type of system in order to pass a municipal inspection.

Anyway the bottom line is the homeowners have to find a way to exchange the hot humid air inside for dehumidified air.

Rick Magee
Building Check Ltd.

17

Originally Posted By: Guest
This post was automatically imported from our archived forum.


www.buildingscience.com-resources-foundations-basement_insulation_systems.pdf


Here’s a link to one of the people that knows more about building science . A lot more.


"edit" the link doesn't work by clicking on it, but if you copy and paste it, it works. I'm sure it has something to do with the fact that I was deprived of video games as a child.

18

Originally Posted By: gbeaumont
This post was automatically imported from our archived forum.


Hi Chad


never did get your link to work ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif) , but I went and did some further research and although the traditional view has been that 2 barriers is OK it does seem that in more modern "tighter" construction it is having to be re-thought.

I like what Rick had to say about the standards being employed in parts of Canada and an air to air heat exchanger has to be a smart idea, as part of the overall ventilation package.

I did have the benefit of discussing this home on the phone with Carla the other day, and was suprised to find that the home has been having the same problem all year.

On reflection this may be a combination of A: a newhome still drying out and B: a lack of adequate ventilation, but I got to tell you I have never seen or heard of one that bad in our area. Hell most builders in New England couldn't build a tight house if their lives depended on it

Regards

Gerry

--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466

Inspection Depot Education
gbeaumont@inspectiondepot.com

"Education is a journey, not a destination"

19

Originally Posted By: dhartke
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Around here the concrete basement wall generally has the moisture barrier on the exterior below grade. On the interior we have board or batt insulation depending on whether furring strips or stud walls are used. Either way it’s a double vapor barrier. I built my home this way 24 years ago and have never had a moisture problem.

20

Originally Posted By: rmeyers
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Carla,


I would definitely recommend insulating the vaulted areas above the bathrooms, to include an appropriate vapor barrier installed to the room/warm side. This condition is undoubtedly contributing to the attic frost but doesn't sound like the whole problem.

More questions than answers at this point!

Am I correct in assuming that the craft paper barrier was improperly installed to the cold side of the frame wall, against the poly barrier or are the two vapor barriers actually 5.5" apart with insulation in between?

Was the exterior of the basement wall properly waterproofed / dampproofed? Can you tell if there is moisture draining out from between the poly and the concrete wall?

Is there a drainage tile system under the basement floor that ties into a sump pump system? If so, does it appear to be functioning properly and how high is the water level in the sump prior to the pump kicking on?

Is there a ventless fireplace unit in the house?
Are there excessive amounts of plants in the house?
Hot tubs, saunas, steam baths or other sources of moisture that may have needed special venting requirements?

Not up to 20 questions yet, but getting there!! ![icon_confused.gif](upload://qv5zppiN69qCk2Y6JzaFYhrff8S.gif)

Have a GREAT Day!!!

--
Russ Meyers