Originally Published: March 11, 2010 10:52 p.m.
In my last column, I talked about water heaters having to be elevated off garage floors. This is because cars and gasoline are usually stored in garages. If there is a gas leak, the gas vapors will stay near the floor. So any ignition source, such as a water heater flame, should be at least 18 inches off the floor.
Gas water heaters manufactured after 2003 have sealed combustion chambers (these are known as "FVIR," or flammable vapor ignition resistant). I was asked why these need to be 18 inches off the floor. The answer is it doesn't matter what the building departments or manufacturers require or recommend. UniSource Energy (our natural gas supplier) requires all gas water heaters to be 18 inches off the floor. How can UniSource Energy make these requirements? They can't "make" you do anything, but they can shut off your gas if you don't comply with their rules. Don't get me wrong - I agree with them that all gas water heaters should be elevated off garage floors. This is a minor expense for some added "insurance."
I had the following comment in my last column: "A gas dryer is an exception to the 18-inch garage rule because it cannot come on unattended. If your car (or anything else) starts leaking gasoline on the garage floor, a water heater can cycle on at any time and possibly cause an explosion if it's not 18 inches off the floor. This is an unattended appliance. A dryer will not come on by itself. You have to turn it on manually. If you walk through a garage with a couple inches of gasoline on the floor and turn on a gas dryer, well, let's just say Darwin would be happy."
I received a lot of e-mails from that column. I confirmed my answers below with the Prescott, Prescott Valley, Chino Valley and Yavapai County building departments.
The first and most asked question was about gas dryers. I was told that UniSource Energy requires gas dryers to be elevated 18 inches off a floor. This seems silly to me (so much for agreeing with UniSource). I immediately visualized a 75-year-old grandma standing on a ladder trying to reach into a top-loading dryer that was elevated 18 inches off a garage floor. I had not encountered this, so I called UniSource Energy and was told that they do indeed require gas dryers to be 18 inches off a garage floor. None of the local building departments require this. In addition to not being an unattended appliance, I was told that the sealed burn chamber on a gas dryer is safer than the open flame on older water heaters. But now home inspectors will have to alert our clients that UniSource Energy can require them to "raise" a gas dryer in the garage.
I was also asked about pull-down attic stairs in a garage. Garage walls and ceilings are supposed to be fire-resistant. This is usually accomplished by installing drywall and sealing all the seams. Since the seams are sealed, most contractors go ahead and paint the walls and ceiling, too. This fire- resistant requirement is why the door between a garage and home should be metal or solid wood and have weather stripping and a self-closer. Most pull- down attic stairs do not seal well enough to be fire-resistant. There are fire-rated attic stairs available, but I have never seen them in a single family dwelling. (A quick search on the web reveals why: they are twice as expensive as the not-fire-rated attic stairs.)
All four local building departments said they do not allow non-fire-rated attic stairs in garages. There is an exception to this (of course!). If the garage attic has proper fire separation from the home attic, then the garage ceiling is not required to be fire-rated. You can install any attic stairs you want (or remove all the drywall off the ceiling if you want).
The last question was about garage floors having to be lower than the interior floor level. I can see the logic in this - so the gas vapors cannot "drop" into the home. I had not heard of this rule and could not find it in the code books anywhere. The local building departments all said they had no such requirement.
I have a little space here, so I want to talk about earbuds. These are the wireless Bluetooth earpieces for cell phones that are less obvious than some headsets. I first saw these in use at a class years ago - by home inspectors of course. I chuckled and greeted each one as Lieutenant Uhura. A year or so later I tried one, and have used one ever since. Now I can't imagine holding a phone to my head. But there are some drawbacks. My phone stays in my pocket, so I do get funny looks when people see me standing by myself having an animated conversation. Of course, I've gotten funny looks all my life, so this doesn't bother me. I've also had people walk up to me and start talking while I'm frantically pointing at the unusual growth in my ear to make them understand I'm on the phone. But I had a new experience last week. I was walking out of a restaurant and called my wife. When she answered, I said "Hi, beautiful!" The two girls walking in front me turned and gave me a dirty look. I tried to make a quick recovery by saying, "I'm doing great, but I need to be careful what I say when I'm using an earbud." I guess the girls understood because they smiled and walked away.
Randy West owns Professional Building Consultants in Prescott. He is a state-certified home inspector and has performed almost 6,000 home inspections in the Prescott area. West is past president of the Arizona chapter of the American Society of Home Inspectors, and currently serves on the Home Inspector Rules and Standards Committee for the Arizona Board of Technical Registration. Contact him at email@example.com.