Are you saying that you have foam at the roofline and your attic is sealed or that you have foam between ceiling and attic?

FOAM ON ROOF LINE. ATTIC IS SEALED.

What is the humidity level in the attic? Are the refrigerant lines anywhere near the problem?

hey hey...we aren't deaf.

we can't hellllpppp with so little info.

so you have an unvented attic with open cell
on the roofline. the plenum is condensating.
intermittent water @ ceiling of kitchen/den.
is the supply plenum over the area where
you have the intermittent condensation?
heavy condensation on plenum?

I see high efficiency units having more condensation
on plenums because air is so much colder.
not uncommon on older plenums with mininum R-value
of insulation. while foam sealing the attic helps sometimes
mastic seal of duct takeoffs, and plenum connections to
equipment done first, then externally insulating the
plenum will solve the problem...but each house
is different.
these issues are not one answer fits all.
so give us more info....

two stage or varible speed air handler? what SEER?
can you give model numbers of hvac & heating
& name brands.
new system? new foam install?
existing plenum & ductwork?

can you post pictures of the supply plenum?
pics of the foam install?

where y'at in La.?

best of luck.

Live in N O . Have purchased Katrina home that was totally redone. But am starting to wonder how well?
Unit is a standard gas furnace. Seer is 13, not super high efficient. Flex duct work is new. Foam is new.
Plenum is over the area where condensation is hitting ceiling in
living room. There are two heaters and handlers. The other one
seems to be okay. Just one is sweating. The intermittent problem in the den ceiling between joints of sheet rock approx. 6 inches in length
seems to come after the rain has stopped for about 5 to 10 minutes. As if it is accumulating somewhere and than just runs out. Have checked roof and heater vent both are new and
show no wear or tear. Can't associate this with anything other than condensation also.
Heating systems are Trane. A/C units are Goodman.
All new systems,plenums,foam, duct work.

Foam...

Plentum

Overall pic

nice pictures!
that picture above...the duct to the far right
taken off the top of the plenum (not the
side tap..the one on the top)
is this the area with the condensation?
that restrictive bend in the duct could cause
problems in air flow.

if the ducts aren't mastic sealed at the take offs
on the plenum..the condensation may be from
this duct. check it out mid day.
oh and mastic is what is very lightly painted
on plenum in pic one, with a better mastic seal
at equipment to plenum in pic two.

you can check to see what type of seal you have
at the duct take offs on the plenum by folding the
jacket & insulation back from the plenum.

when the unit is running..feel around each duct where
it leaves the plenum for duct leakage. cold air escaping
will condensate with warmer attic temps.

is where you have the container on the arric floor,the leak site..as far as you know?

does this leak more after our afternoon its 3pm &
90% RH so lets have a pop up rain shower...or
is it even without pop up showers?

is that a greenbean foam install?

best of luck.

Appreciate your suggestions and help. Am not home at 3:00 pm
I am at work. But my Dad is coming over on Sat with my uncle
and they are going to check out the duct work at the plenum and
the crimp in the run of duct work as you suggested.
yes the only pan that catches water is in the first picture, and you can hardly see it. the others are for what if. it leaks from the plenum all the time, has nothing to do with showers. Please hang
with us you have been our only light and we will get back with you on sat pm with update. i have only had the house since oct so this is my first summer. had no problems in winter.
go figure. ha ha, thanks again.

also check at the soffits in the attic...
where the roof meets the attic floor.
snap a pic or two close up.

this is usually the air leakage site in foam
sealed attics.

not to worry...I'll be around here!

my dad goes to the house tomorrow to check out all of your
suggestions. someone at work told him he has a concrete house and solved his moisture problem with dehumidifiers. i told him this is not the same application as that. am i right? please answer soon.
thanks

I'll be in the field in the morning...mold house to
take a look at, but will be home in late
afternoon.

can you post soffit attic pics? I want to see if foam
is making a seal at roof to floor connections.

gas furnace?
any other gas combustion appliances in attic..
like water heaters?

concrete block houses have no insulation value
of exterior walls, unless they have stud walls filled
with insulation. different dynamic from your house.

well great news. in checking the plenum as you suggested my dad and uncle found many leaks as the a/c man left off the tape.
but also it came to their attention that the heater was not level. in fact it was so off level that the water was running into the plenum and not the drain, hence the water dripping out of the plenum into the roasting pan, they shimmed it up with bricks and put a torpedo level on it and it solved the problem. they left one area with no tape so that the plenum can dry out . and will tape it thoroughly in a day or so. they fixed all of the ducting that was compromised in any way. i can't thank you
enough.

now can i impose on you another problem that i have? i hope you can help me again. please please please.
i have a stairwell that goes up to a single bedroom upstairs.
the walls of the stairwell are closed in like a regular wall. it is sort of like a hall with stairs going up. i of course since the summer started am having trouble with it also. the walls sweat
and the ceiling molds. the a/c man put in a return air on the stairwell wall and this causes the walls to drip water.my bedroom has a hallway leading to a hand basin and than a shower and commode. today my dad took the grille off of the return air in the shower commode room and although the grille
was 12x22 only a pie shaped opening due to the roof line was present about 6" high by 6" long but in a slice of pie shape.
my bedroom is warm. i have to turn the a/c downstairs to 65 when i get in from work to at least be able to sleep as there is no thermostat upstairs. my father could put a floor register in as beneath the floor in the bedroom
there are two 10" registers side by side and the room is freezing. he wants to know can he turn this upside down and cut a hole in the floor and send it into my room. what would be the pros and cons of this and do you have a better suggestion.
of course pictures would help and we will send them on monday. do you think adding a small a/c line on the stairs would help. the a/c man said the return air would offset the a/c vent so he went with just the return air and that made more of a problem. so we know not to trust him.

Here are pictures of the stairway and upper bedroom. The total area is 366 sq.ft. Any help is greatly appreciated!

looking from bedroom into hall and bath

register in bedroom

hallway register, which is always sweating

stairs going up. mold problem is on ceiling, which has no attic over it, only spray foam insulation and roof

stairwell ceiling

return air at top of stairs, when open makes moisture worse

return in upstairs bath, with small, pie shaped opening behind grid

Beryl, when you wrote "tape", I hope that you don't mean duct tape. You need to seal up your system with mastic tape.

I am having a hard time understanding the problem, but you might be sucking in lots of outside air due to pressure differentials between rooms. Leave all your interior doors open and see if this helps. I don't understand how your walls and ceiling can be so cold as to have moisture condensing in the INSIDE of the drywall. Maybe it is condensing on the outside and wetting the inside?

Is that ceiling below the sealed attic? What is on the other side of the damp walls?

Get some inexpensive electronic hygrometers and place them in several places in your house and take readings a couple of times a day. Check them against each other for accuracy. Let us know what you find.

I suspect that attic foam seal is not air tight.
if hot humid air is entering at eaves/soffits
then the walls/ceiling condensing makes sense.
hot humid air meeting cooler sheetrock..

as for the return that has the half moon
return duct...it is starving the system for
return air.

run by & take a look Peter! tell me what you find.

Beryl...take some close up pictures where the
foam meets the attic floor. in the eaves/soffit area.
I need to see where the foam touches the attic floor
in these areas.

any idea who did the install of the foam...or the
hvac system?

Is that a skylight in the hall??
& is that an attic access/hatch??
there should be NO return air in bathroom.

too beat tonight to give this much thought...been
wrestling all day ( & last week) with a mold house.
I should just stop looking inside the supply plenums..
each time adds another week of work!
but...the mold issues will be solved...there is that!

best of luck.

Here is another example of how easy it is to get moldy plaster or sheetrock in mechanically-cooled homes in this area. We rented a (non-flooded) house in New Orleans after Katrina. It was an older home, 1930ish, with an open crawlspace. There were 4 window units. There were soffit and gable vents.

For some reason someone had stopped up the soffit vents from the outside. I think that caused air to be drawn up through the stud spaces from underneath. Everywhere there was furniture against the walls, there was a moldy area in the plaster.

foam at eaves and attic floor

foam at eaves and attic floor

foam at eaves and attic floor

When we discovered the problem, we consulted with a local hvac company specializing in conditioned, foamed spaces. They suggested that our first step be to have the attic re-foamed, since the foam was done wrong (sprayed on top of fiberglass insulation!), which we did. They also suggested putting a return in the stairwell to circulate the air, which we let them do. After both of these things were done, the problem was worse. What started as mold flecks on the ceiling of the stairwell that could be wiped off turned into visible condensation. We blocked the return and started with an oscillating fan at the top of the stairs, and problem solved. But we don't want to live with the fan, and the air in the stairwell is still very hot, just moving. When we had the visible condensation, the foam company came back to check their work and refoam anything they might have missed. There is a skylight in the stairwell, another in the hall with the attic hatch next to it, and another in the bathroom. The bathroom and hall temperature are somewhat comfortable, but bedroom is hot, and we suspect the heat from the stairwell keeps it that way. It was suggested that we completely or partially block a large return downstairs, 10 ft. to the left of the foot of the stairs, which would force cold air from the bottom of the house up the stairs. It was also suggested that we put an a/c vent in the stairwell to condition the space, which in turn would cool the bedroom. A/C installation done before we bought the house, but we suspect by fly-by-night people. All help, advice, and suggestions are SO appreciated! Thank you!!!!!!!!