Hamilton Prep Coat...

Halo

Drywallers sprayed the prep coat mid-day with interior temps near 70 deg. 75 gallons were applied then electric heat and fans were left on over night. Outside humidity was near 75%. Next morning moisture was running down inside of covered windows (31) and onto walls. Things were uncovered, windows were cracked and multiple fans were left running. Outside humidity dropped to near 50%. Things dried up pretty quick and looked good. Forward two days later and the house has been a constant 75-80 deg. with good air movement. No signs of moisture on the inside windows at all. The hamilton product appears to have shrunk creating cracks in the corners and over taped seams. These cracks are only in the build-up of the prep coat.

Finishers will return to skim coat and final sand in a day or two. These cracks have me concerned.

Any insight/thoughts?

TracyMC

Humidity has never been a problem, as I live on the dry side of the state, but you may want ask your finishers if they are adding mud to the mix and shooting it as a Level 5, I used to see finishers do this all the time over here and I have seen that issue before, usually too much build up, and too much added mud. If they did'nt, get a hold of GTS and get the contact info for the rep. Vince he is based out of your area, and he will come out and look @ it for you, he' s always been good about backing his products.
Tracy

Halo

Thanks for the reply

They are on it this morning. No mud was added. They have a great rep as you said.

Brocktologist

What did the finisher's say? I'm sure they are experienced with the Hamilton products and have it handled.
Tell them next time either wipe off excessive product over the window plastic or just pull up the bottom and staple a few inches up so it'll catch it before it slimes down the wall.

Halo

It seems the excess humidity from being closed up tight raised the tape at the butts. Being smoothwall the butts had been sanded very close to the tape. The Hamilton shrinks as it dries appearing to add to the tape being pulled up. I assume the cracks through the prepcoat on the inside corners is also related to shrinkage. The drywallers had a guy cut the butts out entirely and prep for re-tape. I will see more of the crew tomorrow and find out about the remaining cracks/shrinkage on the inside corners. I see no way around top-coating or sanding all noticeable cracks for fear of them telegraphing through.

Halo

Considering the amount of re-work that has been done since the prep coat, would you fallow up with another coat...or simply allow the use of a high build primer and sand?

This home has alot of windows and up-lighting, many walls will be white and they are smooth. Most around me say primer, sand and move-on. You know what the tapers and painters position is...opposite.