I was contacted by a previous client I did an 11th month inspection for two years ago about some pretty bad drywall cracks that have recently popped up throughout the house.
I walked through everything and other than a couple diagonal cracks at window corners, the cracks follow the edges of the drywall. I could even see light coming through them between sheets of drywall at the ceiling while in the attic.
So one thing on my mind is that a contributing factor to the extent of the cracking is that this house is empty for half the year. During the summer they keep the thermostat between 85 and 90 while they’re in Canada and I wonder how much that may be contributing, along with nobody living in it opening doors or windows, and without maintaining a normal year round indoor temperature.
Am I on a reasonable thought track? I mean, I know that drywall cracking is normal stuff but I haven’t seen many homes with cracks this big and they asked me out to get my opinion on whether they were structural or not. If so, what advice have others given clients regarding temperature suggestions while the house is unoccupied?
What is the typical summertime temperature and humidity where the home is located?
I’ve been to AZ in the summer and winter, and I know just how hot/cold it can get, but I don’t know what micro-climate this home is located.
Generally, (in Minnesota), I suggest only a difference of roughly 10 degrees from normal averages in summertime, (winter 20 degrees max to prevent frozen pipes). People hate that because we tend to get high humidity and depend on the A/C to assist with managing it. MN folk are big time into dehumidifiers, but IMO, those only go so far and would never leave them running longterm when not present.
This past summer was among the hottest, with our temps regularly between 110 to 120, starting a little earlier than normal in around May through to maybe about 3 weeks ago or so. We also didn’t have our normal monsoon season, so quite a bit drier than normal, too.
Danny, I have worked with Dale Duffy a few times in AZ, and my Aunt lived down the street at that point. I first consider the Region where we are inspecting. Are there weather records that are conducive to building degradation, etc. My job now is specifically to diagnose building performance associated with adverse conditions.
As I am sure you also believe that these cracks are not alone a significant structural concern, seeing you have a history concerning this property.
This is a weatherization issue. Not what I think you’re looking for, but air leaks are the largest energy loss out there. Here in TN, bring our air into the house with an A/C can be catastrophic! Not so much where you are.
Again, air leakage, along with latent heat (moisture) entering a building is an issue hen the A/C set point is below the dew point temperature. 90F is never below the dew point in Az.
Without other testing, I can not even dream something up with this information considering your region.
Unless the attic is sealed at the roof, you have a workmanship issue. Did they spray the roof deck and all exterior openings in the attic? If not, I would still recommend that be taken care of. But I would not consider the cracking to be associated.
rcloyd
(Russell Cloyd, KY LIC #166164, IN LIC#HI02300068)
5
Daniel,
Drywall cracks like the ones that you describe can be structural in nature. Unstable soils, seismic activity, settlement or improper construction practices can be contributing factors. I would recommend referring them to a good structural engineer.
Thanks for all the ideas of what might be causing this. I just don’t feel that it’s really structural in this case. The house is empty half the year, we had super hot and dry weather conditions, no one living in it to take showers, cook food, breathe, etc - anything that could add any moisture to the air inside. The cracking of the greatest concern is all at drywall joints where the mud has cracked. The house is on a slab, the attic is sealed and there isn’t much airflow throughout the interior while they’re in Canada half the year except when the ac system kicks on at 85-90 degrees. It was 110 degrees and hotter most of the summer outside with overnights down to 80-85.
I guess I was really looking to see if my thought process was going along a valid path, and if so, is it possible to prevent some of these from coming back by maintaining more reasonable indoor temps while it’s unoccupied. If my thoughts are flawed, how should I rethink this through?
