10. Tree Branches Rubbing On The Roof Tree branches do a lot of damage to roofs. Just think about branches rubbing on the roof all day long while the wind is blowing. This adds up to a lot of damage. Tree branches too close to the roof will also give squirrels, raccoons, and other pests very easy access to the roof.
9. Double-Tapped Circuit Breakers Every circuit breaker in the main panelboard should have only one wire connected to it, unless the circuit breaker is designed for more than one wire. Most aren't. Sometimes the fix for this defect is very quick and easy, sometimes it's a major project.
8. Bath Fans That Don't Exhaust Properly I start my home inspections by turning on every fan in the house, and I make sure that air gets exhausted to the exterior. I find a ridiculous amount of fans that make plenty of noise, but don't move any air. The problems can be caused by disconnected ducts, ducts that aren't continuous to the exterior, blocked internal dampers, stuck external dampers, or kinked ducts. A bath fan exhausting in to the attic is always the worst.
7. Missing / Improperly Located Smoke Detectors Smoke detectors should be present in a common area on every level and in every bedroom, and the installation instructions need to be followed. I can't tell you how many smoke detectors I see tucked away in to corners – this is never an acceptable installation, because smoke won't get there fast enough.
6. Missing Cover Plates Missing or broken cover plates at outlets and switches are shock hazards, period. Common problem, easy fix.
5. Improperly Wired Outlets Ungrounded three-prong outlets and outlets with reversed polarity are very common defects. These are shock hazards. You can check the outlets in your own home with an outlet tester that costs about five dollars.
4. Missing Carbon Monoxide Alarms. Minnesota requires carbon monoxide alarms within ten feet of every sleeping room. Lots of people put them in the same room as the heating plant; that's fine, but it's not required.
3. Poor Water Management This consists of the same thing every time – negative grading and improper downspout extensions. This is almost always the cause of wet basement and foundation problems. The grading around the house needs to slope away, and downspout extensions should take water well away from the house. Improper downspout extensions are worse for the foundation than no gutters at all.
2. Missing Anti-Tip Devices At Ranges Ranges have been sold with anti-tip brackets since 1991, but it's pretty rare for me to find the brackets installed. These are required to prevent ranges from tipping over, which could cause serious injury or death to a child.
1. Attic Bypasses I find these all over the attic on almost every old house I inspect. Attic bypasses allow conditioned household air to leak in to the attic space, and they can reduce the effectiveness of insulation by as much as 70%.
Reuben Saltzman, Structure Tech Home Inspections - Email - Minnesota Home Inspections
