I had a few things come up this week that made me think of this thread:
1. A colleague had a client under contract on a new build, and they have a mold sensitivity so they tested for it. Turns out the builders buttoned up the walls during a storm while there was significant moisture present and now the insides of the walls are full of mold. They terminated the contract.
2. I learned that 80% of the new builds in our area are testing positive for meth.
3. I did an inspection on a new build and found that heavy equipment had been driven over the brand new sewer line, breaking a connection and offsetting the line.
4. I talked to a structural engineer who said he much prefers older properties because he can see where settling has occurred, and assess how bad it is, whereas with new construction it's harder to tell.
So, newer is definitely not always better!
The list of things to look for on older properties is well-known and pretty straight-forward. Electrical: check for knob and tube, aluminum wiring, Federal Pacific Electric panels or old fuse boxes, ungrounded outlets, lack of GFCI's etc. Plumbing: check for galvanized pipes, leaks. Sewer line check for bellies, cast iron/ old clay/ offset lines, broken connections, roots, mud in lines, main tap. Check for foundation/structural issues. Mechanicals: check age and condition. Asbestos, lead, etc.
The list for new builds can be a lot trickier (poor construction/ construction defects, new materials being used that haven't stood the test of time yet, foundation issues from expansive soils or bad concrete being used (harder to know because the damage isn't visible yet), sewer line might be already jacked up or done wrong, windows or roof may not have been flashed properly but water damage isn't visible yet (I've seen new builds where you could literally see daylight coming in through gaps around the windows), grading or drainage issues, truss rise, nail pops, water intrusion, cheap appliances only made to last a few years or poorly installed, dirty ducts from registers not being covered during construction, wood shrinkage cracking the sheetrock, doorframes off/sticking doors and windows, apparently mold and meth may be present already... both old and new require due diligence and an experienced inspector.