If you're buying a new construction home, get it inspected by a private home inspector.
I could wax on and on about how important home inspections are for new construction, especially if the builder tells you that a private home inspection isn't necessary, but I've found that photos are far more convincing than anything I could say. I took all of the photos below at homes in Minnesota that were either new construction or only a couple years old; the issues that you're seeing are all 'original' issues; they weren't created after the homes passed their final inspections by the city.
Click on any of the photos for a larger version.
The first thing that I typically inspect is the roof lines - I start doing this as I drive up to a house. When valleys dump next to a wall, or even worse, in to the back side of brick veneer siding, you're asking for trouble. These roofs are designed to fail.
I took the photo above at a house that was almost ten years old. Thankfully there was a small portion of unfinished basement where I was able to pull the fiberglass insulation away from the rim space to confirm my suspicions; this had been leaking for a long time. I really wanted to know what it looked like behind the siding... but my home inspections aren't invasive or destructive so I couldn't get all 'Mike Holmes' on them.
I've written several blogs about deck construction defects, but unfortunately handy homeowners and weekend warriors don't have the market cornered when it comes to shoddy workmanship. Yes, I find plenty of deck defects even on new construction.
The most common deck defect that I find is improper nails used on joist hangers. The nail I'm holding in the photo below isn't even half as long as it should be. I seem to find this defect at just about every other deck inspection.
When special / non-standard joist hangers are needed, there's about a 20% chance that the installer will use whatever happens to be in their truck. In other words, this is usually done right, but I still find a lot that are done wrong. The joist hangers shown below were the wrong ones for the job and won't hold what they're supposed to.
Stairway stringers seem to be a hard thing to cut.
Deck stairways aren't difficult to attach properly, but some people sure make it look difficult. Those long metal straps shown below aren't designed to do anything on a deck, and they're certainly not holding this stairway up.
In the next two photos, the deck stairway is attached to a piece of siding trim with deck screws. This is ridiculously wrong. Yikes.
I don't find a lot of electrical defects on new houses, but I do find them. In the next two photos below, there are double tapped circuit breakers and double tapped neutral wires. These breakers aren't designed to be double tapped, and neutral wires are never allowed to be double tapped. I honestly think the electrical inspectors never even looked inside these panels, because these are blatant violations. By the way, these weren't at the same properties.
This next violation was more comical than anything else; it's no big deal, but someone obviously missed a day of training.
There are two common defects that I find on new construction houses all the time - one is test plugs or test caps still in place at the plumbing vents. Test caps need to be installed at plumbing vents so the drain, waste and vent system can be pressure tested. After the pressure test is done, someone needs to get up on the roof and get rid of the caps or plugs, but this is often forgotten about. This effectively disables the vents.
The other plumbing issue that I find all the time with new construction houses is missing access panels for bath tubs. Either there is just no access provided, or someone installs a panel but never puts a hole in the wall. I always chuckle when I remove an access panel and there is nothing behind it... but I'm no longer surprised.
I find a lot of the same HVAC installation defects over and over. In the photo below, the AC units should have been at least 24" from each other.
Venting for high efficiency furnaces is done wrong all the time. I often find installation manuals that have never been opened. In the photo below, the vent terminals for the furnace were installed wrong; the diagram below the photo came right out of the installation manual.
Any time the vent passes through an unconditioned space, it needs to be insulated. This doesn't always happen.
Powervent water heaters have a huge list of things on the outside of the house that they can't terminate too close to; in the photo below, the vent terminates way too close to the gas meter.
Heat recovery ventilators (HRVs) have their own required clearances - for instance, the intake and exhaust need to be lilatorocated at least six feet from each other. The HRV shown below has the intake and exhaust with about four feet of separation.
Most HRVs need to be balanced when they're installed; if there are no screws present to lock the dampers in place, it hasn't been balanced or someone wasted their time balancing it and it needs to be done again.
Most structural problems manifest themselves years down the road from latent defects, but sometimes they're obvious. In the photo below, someone took a sizable notch out of one of the beams. If this was part of the original plans, great... but I'd bet anything it wasn't.
This next photo is one of my favorites; someone bent the heck out of this stairway stringer bracket and used it on a floor joist. You can see that the bracket is actually splitting. Just in case you needed a reminder, this is new construction.
As I've said in previous blogs, attics should always be inspected, whether the attic access panel has been 'sprayed shut' or not. In the photo below, the roof vents weren't properly lined up with the holes in the roof sheathing, which significantly reduces the total amount of attic ventilation.
Broken truss chord - I'm guessing too many bundles of shingles were unloaded in one place. I can't be too critical of this because I've done it myself, but the big difference for me is that I fixed it after I broke it.
Same thing, different house.
This photo below shows a disconnected duct from a bathroom exhaust fan; just think about how much moisture would get pumped in to that attic over the years if it never got fixed.
When truss manufacturers put green stickers on every truss saying "Permanent Lateral Bracing Required", I expect to see permanent lateral bracing installed. This new construction house didn't have any.
Finally, here's one of my favorites. I took this photo at a five-year-old townhouse that had two separate attic areas. One was insulated, one wasn't. Wow.
I have a lot more photos that I could share, but hopefully I've made my point; just because a home is new doesn't mean it's right. If you're buying a home, new or not, get a home inspection.
Reuben Saltzman, Structure Tech Home Inspections