One VERY IMPORTANT thing I do on a one-year warranty inspection is sweep the house with my thermal camera to see if there is slipping insulation.
It is important to do this because the camera can definitively determine if the insulation has actually slipped. Done before the warranty is expired puts the fix back in the builder's lap.
But be careful. Some "one-year" warranties expire in 11 months! That's a another little trick employed in recent times. So check your contract carefully before you hire a home inspector.
These are two different views of the same room. It is the fourth level of a single-family house.
I love four levels in a house. It makes for a very fun, versatile room and there is little wasted attic space.
In this case the ceiling is peaked. The drywall you see is not very far from the roof.
These images are taken in the morning. This room faces east and west.
The image on the left is the west side. Part of this vertical wall is exposed in the attic space. As such the entirety of that wall should be insulated.
From the attic it was evident that the insulation had come loose and some had fallen down. That purple spot is an area where the builder dug through the insulation to get at something down the wall, and never replaced it. That is the coldest spot in the image, and 42F. By contrast, look how warm the rest of the wall looks!
And look at how the camera organizes the 307,200 pixel points of temperature in each of these two images. The walls look warm (orange and yellow) in the left image and cool (lavender and blue) in the right image because the camera is demonstrating contrast. The temperatures in the walls and ceiling are not that much different between these two images, but appear so because of the temperature contrast.
The image on the right is the east side of the same room! Look how the sun on that side of the house is heating the attic space there. And again, look at how poorly placed the insulation is, literally coming off the wall!
Why does insulation slip? Insulation has flaps on the paper of the vapor retarder stuck to one side. Those flaps are there for a reason! AND THAT REASON IS TO STAPLE IT TO THE STUDS!
When it isn't stapled, over time, it will sink. Why? BECAUSE GRAVITY WORKS! Staples are how I determine the quality of the insulation job on a pre-drywall inspection. I do that so that the one-year inspection doesn't reveal what this one has.
I have seen very high cathedral-ceiling walls where the insulation has slipped down about one third in the first year. That is a difficult problem to fix because it requires removing and replacing drywall. In this case it isn't so hard to go into the attic to staple this stuff up properly. BUT IT MUST BE DONE! And the time to catch it is during the warranty period!!
These people have complained that this room was inordinately hot and cold. Well no wonder!
My recommendation: get a one-year inspection on your home! And if possible, hire a thermographer to try to catch poorly insulated areas. You will be far more comfortable if you do. Peace of mind is worth a million bucks! It's certainly worth the price of a thermal image inspection. And remember the other benefit - thermographers are all really cute.