What is "this"?

Wait and get your builder's response.

Well...clearly there's water leaking into your interiors from your exterior walls.

From the lack of information which we have here, we have no idea of the state of your construction or why it may be leaking.

One thing's for sure: walls shouldn't leak.

Show this to your general contractor and ask for explanation.

Good luck on your project.

The biggest concern I would have is mold within the wall structure. Once mold is present in any permeable material (wood, etc.) it cannot be killed and any permeable materials with mold must be removed.

Take a photo from the outside at or above the floor level. I think you may mean the wall is covered with Tyvek or something similar. Water is probably getting into the wall cavity at a window and running down to the floor deck.

If the only thing on the exterior is tyvek, then they shouldn't have started drywall inside.

This is cross-woven housewrap, IMHO they all leaks like a sieve. You need siding stop the leaks. [or total replacement]

It doesn't look like building wrap to me, it looks like 4' x 8' insulated sheathing, without taped seams.

Or pieces of building wrap applied somehow to the sheathing with a lot of seams (a questionable practice).

It appears to be ThermoSheath Blue structural sheathing from National Shelter Products. A tick over 3mm thick.

I would ask that the wet drywall and insulation be replaced. The subfloors will be fine.....subfloors almost always get wet during the framing phase of construction, and are designed with that in mind. They will dry out.. Insulation and drywall should not be getting wet, however.

The logo says its "DRYline TSX Structural Weather Barrier" which is similar to Thermo/Sheath Blue from the same company. It acts as a structural sheathing as well as a water-resistive air barrier. Its made of multiple laminated plies of water- resistant paperboard fibers adhered with a water-resistant adhesive with either an exposed polymer or aluminum foil facing. If its the "blue" sheathing. its a little thicker than 1/8".

The installation instructions don't appear to require joint tape but the company sells DRYline Sheathing tape to improve the performance of the sheathing. Perhaps a house wrap was installed over the sheathing.

Maybe it was not taped or covered when the GC claimed the building was dried/weathered-in and ready for interior work.

If this "sheathing" is foil-faced, does it not act as a vapor barrier on the cold side of the insulation? I hope its vapor permeable and the joints were taped.

Was there a vapor retarder under the drywall? Do you have photos?

The subfloors will be fine.....subfloors almost always get wet during the framing phase of construction, and are designed with that in mind. They will dry out..

Framing phase is very different from dried in phase. When stuff gets wet during framing it dries out relatively quickly - low chance of mold.

When any framing members (2x, subfloor, etc.) get wet after dry-in there is much greater potential for mold. This is why when there is a water leak of any sort it is critical to immediately (within minutes/hours, not days) remove drywall, insulation, carpet, or other stuff and begin removing moisture from all porous materials (wood framing members) quickly.

Once mold begins to grow it is impossible to get rid of with porous surfaces because the only chemicals that can kill it cannot penetrate wood. If mold has begun to grow in wood the only solution that I'm aware of is removal of the wood.

In the OP's case, has wood behind the drywall been wet long enough for mold to have begun to grow.

I can picture water running down the shinny surface of that sheathing and then rolling under (liquid adhesion) at the seam to the inside. It would seem that those seams need either a really good tape job or a drip edge (and bevel?) to prevent water for coming in.

To start growing any fungus not only needs water but warmth. In cold dry conditions its not likely to occur so unless the house is being heated and the moisture is high from taping, it might not begin to grow. But, in any event, the wall cavity can be dried by opening a hole at the top and bottom. Use a hole saw to be able to patch it more easily. If you are impatient or the conditions are not ideal, you could attach a shop vac but moisture vapor moves to equalize itself like air pressure only much more slowly. You could always open rectangular sections between studs with a mat knife and pull the insulation out. This is not difficult work.

Given the snow on the ground, I would be more concerned about how interior moisture moves through the exterior wall if wrapped with foil. I would expect to see foam insulation in the walls.

If the sheathing joints were not taped, this builder is in the habit of taking unwise risks.

Was a vapor retarder installed on he inside of the exterior walls before th drywall was installed?

If not, there is another way to remove water from inside walls if you act fast. Hire a company that deals with food damage. Here is an example of how they draw the water out of a wall.

in any event, the wall cavity can be dried by opening a hole at the top and bottom.

From everything I've read this is no longer considered effective in most instances. It does not remove enough moisture fast enough to prevent mold from beginning to grow. Many people who later got sick from mold had done this earlier thinking that it would be sufficient.

My understanding is that If there is moisture in the wall cavities then drywall and insulation must be removed immediately and all porous materials dried quickly.

One more note. I believe that just because there is mold in porous materials does mean that there will be a problem. For instance, if the wood is very dry, all surface mold is killed and the wood is kept very dry then the mold will remain somewhat dormant. If this wood ever gets moist or wet then the sub-surface mold will begin to grow again and this is when it begins to cause serious health issues.

Reverse lapping could also be allowing water to penetrate. As shown in the video posted by RES 3d Sketches, (who seems mighty familiar) a moisture meter would pinpoint excessive moisture in the walls.

If I had to demolish and rebuild every part of every home that showed some water leakage during construction, I'd still be working on my first home!

a moisture meter would pinpoint excessive moisture in the walls.

A moisture meter may tell you if the drywall is wet, not guaranteed though. It will not necessarily tell you if the wood framing or insulation is wet. It's a good tool for telling you if you do have a problem but it cannot tell you that you do not have a problem.

It would worry me. A lot!

Your builder is both right and wrong and needs to brush up on his building sciences. He is right that both installing drywall and running propane heat put a lot of moisture in the air. He is wrong that the problem will go away once construction is complete... you will create humidity when you take a shower, run laundry, do dishes or run a humidifier. The problem is he has created an ice cold surface that any humidity will freeze against. He needs either a lot more rigid insulation to prevent the cold surface or none at all.

Properly used moisture meters are quite effective in finding current moisture.

So the builder says it is moisture from using propane heat and that it forms frost on the inside of the dry line material that is now melting to subfloor since they switched to the HVAC system.

In most homes without sufficient external insulation, some moisture would be turning to frost on the interior of the sheathing; this is from moisture moving from the interior and trapped to one degree or another behind the sheathing. Usually, you would never know about it and never see evidence of the melting.

You wouldn't normally use propane burners inside a home! So you may be fine in the long run.

I often use propane heaters during the winter to allow work to continue. But I have never seen bulk water running out of the walls on the floor.

Why not open a wall and see what's happening?

Yeah by his own admission, that insulation is likely wet/ruined. The walls where visible moisture has been wicking in should absolutely be opened and inspected (you should be present!).

Builder has a plausible explanation. We have one interior photo.

Is the status of the interior "finishing drywall?"

A gut check in with the building inspector or another local builder would help as my zone doesn't experience your cold temps.

It is completely normal for frost to form on the inside of sheathing in the wall construction of the OP's home in a cold climate. Typically, it causes no damage even on OSB walls. Likely much less on the composite sheathing being used. Air flow during summer dries out the wall. And certainly some forms of insulation are more resilient to dampening than others.

But running water (bulk water) is certainly not a comforting signal. I've never seen it in the homes I've built in our cold climate (Toronto GTA) while running propane heaters during the winter.

How interesting, I googled Dryline and it took me to this thread. Your home OP looks identical to the one I am building in SW Ohio! I bet I could guess the floorplan and builder and be right.

@Teresa, which home is this? Is it a Fischer Home in SW Ohio? I have similar issues dealing with the builder now on it.

Yes, Batavia. Home Inspector did not seem concerned so we continued without arguing more on it.

Teresa, how do you like your new home?

We like our Denali a lot. I think most disappointments are due to all of the options that we did not pay for because of sticker shock at selections meeting like cheapie vinyl floors peeling a bit, no bay window. Some disappointments with things they just did not offer at this level like vanity counter seat area and light in shower stall. Windows are a bit drafty though they claim high efficiency.

Good to hear Teresa, my wife and I are building the Foster about an hour from Batavia.

We were also surprised at how much they wanted for nice flooring. So we went with a lvl 2 carpet, and vinyl sheeting in the home.

I knew this was a Fischer Home as soon as I seen it lol. I know this is an older thread, but thought id put my 2 cents in in case someone else cones across it. The material on the outside of the house is a structual weather barrier. Not only is it water resitant, it also holds a slight R-value, helping to insualte it slightly. There is manufacturer's specs on the install, that is also inspected by the building inspector prior to being covered in siding. It must be stapled in a certain pattern, or will fail the framing inspection. I actually subcontract for Fischer, and have talked to more than one inspector about this product. They say its a better alternative to OSB. Hope things are going well, and you’re still enjoying your home.