Home & Garden Columns

About the House: Strapping Young Water Heater Turns 10 Years Old

By Matt Cantor
Friday April 20, 2007

I am a total crank. I admit it. I can’t help myself. I think this just the way Lord Shiva made me and there ain’t too darned much I can do about it. Some things just rile me, chafe and get under my pink semi-translucent skin and one of those things is the utter and thorough inability of just about everyone in the building trades to properly strap a water heater.  

Now, this may seem a silly, small and niggling thing but it’s not. It’s genuinely important and I’ll take a few minutes (if you’ll bear up) and explain why. I will also, of course, explain how one ought to do this vital task). 

In the January of 1997, just about 10 years ago, California began enforcing a law that required the sellers of homes to strap their water heaters prior to delivery, to their eager new recipients. At first, it was understandable that plumbers and handyfolk would get this wrong and so I made excuses and waved the little booklet around and asked that these be done again.  

No problem. Well, of course they nearly all got fixed wrong and as time went on, my face got longer and more beleaguered and eventually, I just lost all composure. Now this job isn’t all that complex. It’s also been 10 years and only a small fraction seem able to get it right. I don’t get it. I think the real problem is that nobody really understands what’s at stake.  

I’ll never forget this one image from the Northridge earthquake of 1994 (the one that resulted in the law). A field of burned lawns and those funny rectangles of concrete representing the former homes of football stars and grocery clerks. Well beyond the little squares lay the remains of water heaters, often yards from each house. 

It took me a minute but the fuzz cleared to reveal what had happened. Water heaters had caromed about in these houses and crashed through doors or walls and ended up far from where they had perched before things went all wonky.  

Water heaters are very heavy and their gas and water connections are far too flimsy to restrain so great a mass. Also, earthquake forces love objects like this and slender straps become something of a joke. Only a serious pair of heavy straps, bolted into framing seem able to work when the shaking gets grand. In the absence of these, gas lines torn open, deploy their ordinance and the result tends to be quick and devastating. 

The architect’s office of the state (yes, Yuri, there is a State Architect) published a short booklet to go with the new law and I see them from time to time, usually taped onto the front face of a poorly strapped water heater just for comic relief. If you read it, it’s pretty straight forward. Two straps of heavy gauge metal (you can buy a kit in most hardware stores these day that’s plenty adequate) for any water heater of up to 52 gallons. I’ve never seen a 52 gallon water heater so I’m not sure who came up with that! 

The straps need to be bolted, not nailed, not screwed, not glued, bolted into the actual framing of the house. If you want to bolt to something else, you need to make sure that the thing you bolt to is well bolted to something else. I’ve seen more than a few goofynesses related to this but it’s just not that complex if a little effort is applied. 

Straps need to hold the water heater against some surface and not merely off in space. This is perhaps the most common cognitive failure I see. A pair of heavy straps might be used but they leave a large gap between the water heater and the wall, as though the water heater will know, when the earthquake begins, that it should observe this perimeter and not attempt any silly business like bouncing off the wall and shredding its straps (which is exactly what it will do).  

No strap or bolt is sized to withstand the force of 500 pounds bouncing off a wall. They just don’t make them big or strong enough. The only thing that really works is to keep the water heater from developing that level of acceleration and the only way to do that is to read the instruction (it says it right in the booklet and shows it in every picture for those who don’t read) and install the straps so that there is no bounce room. Straps should tighten the tank right up against the backing and thus prevent the sort of movement that can liberate the beast. 

It’s really best and easiest to do this against an exterior wall (from the inside or outside) and even easier in a corner. Nonetheless, sometimes they have to be strapped inside the basement some distance away.  

I’d generally opt for replumbing at the better location but when there is no other choice, one will need to build a small wall right behind the tank. Said wall will have to connect boldly to both top (floor framing?) and bottom (basement slab?) with the same level of bolting that the strap itself demands.  

Another thing to be tuned into is the spacing of the straps. One strap should be just above the controls (within 4” if possible) and the other should be near the top (within 9”). Now this seems logical but I will see one in the middle and one at the top all the time as though the lights are on and nobody’s been home for a while. 

There are a range of other bizarre aberrations often seen but let it be sufficient to say that not 10 percent of these jobs are done vaguely right and there’s just no excuse. The instructions are readily available and the materials are cheap. Also, the consequences are really quite serious. 

True, I would very much like every house in the Bay Area to have a valve that will automatically shut off the gas in a quake and, yes, this would eliminate the fire concern from flying water heaters but there is at least one other darned good reason to overtake inertia and get this done and it’s all about clean drinking water. Every water heater contains many gallons (30, 40, 52?) of clean, fresh drinking water (unless you haven’t used your hot water lately!) because water is constantly flushing through the tank.  

If you have your water heater strapped and it’s stayed in one place, you might be the only folks on your block with fresh drinking water in the sober days that will follow a local temblor and that’s nothing to shake a divining rod at. 


Got a question about home repairs and inspections? Send them to Matt Cantor at mgcantor@pacbell.net.