Is it included in the overall square footage for what? There are many ways to calculate square footage.

Ours is calculated in the square footage that was listed on the real estate listing and how it is listed on our tax records. Of course, it doesn't even account for 4 square foot, so I'm unsure on why it would really matter. (Our current house is a one-story rectangle, so it is pretty easy to get the square footage.)

*One word of advice - if you do place yours outside, depending on your climate, you may have to watch for freezing pipes. If gas, the space will have to be vented. If electric, you should be able to insulate better.

I think your answer is, "no." ....... our WH is in our garage (which is standard practice here.) The garage area is not calculated towards square footage. Our patios are not calculated as square footage. etc...

There are different calculations and standards for square footage. There is "under roof" square footage. That includes garages, porches, breezeways, and any other areas that are under the home's main roof. There is "heated and cooled" square footage. There is a room's actual square footage which will be different than it's architecturally drawn square footage because of the width of the walls and wall coverings.

If you are talking for construction purposes, what difference does it make? You will still have to pay for all of it even if it's not HVAC'd. If you are talking for tax purposes, then talk to your local tax office. Different locations assess differently. Some assess all of the square footage under roof, while others only assess HVAC'd living space.

The ONLY way that I'd place a water heater exterior to the home is if you lived in climate zone 9+. Even then, you'd need to insulate, and I'd personally want to heat tape the pipes and include an outlet for that just in case you had a 50 year low.

I think I may have derailed my own thread with the reference to square footage ~ I'll blame it on sleep deprivation! My main purpose for starting the thread was to find out advantages and disadvantages for locating a water heater along an exterior wall with access from the outside. One of each came to my mind: Pro = easy access for maintenance; Con = insulating enough to avoid freezing. Any others?

In our experience with our own house:

PRO: Able to be in a better location without taking up any room on the inside. It is basically at the end of a closet running perpendicular to the house. Main part of the closet is open to a bedroom. Then there is a wall separating the end where the water heater is. It is accessible from outside. We have already had to change it out once and need to drain it again soon (sediment build up). I believe the outside location was pretty easy for this as we were able to back the truck up pretty close and didn't have to manuever it much. The new one was not that heavy, but the old one that was filled with sediment was almost more than we could handle.

CONS: We don't get hard freezes here very often, but when one is forcasted, we have to turn a light on in that closet to help with frozen pipes. I don't know how much of an effect the space being unconditioned has on its efficiency during the winter.

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At my parents old house, in a bedroom addition, there was a separate water heater added. It is actually in one side of the reach in closet in a bedroom. (Electric, not gas.) We'll move into that house eventually and I dread having problems with it due to how hard it will be to access it - probably have to removed a good deal of stuff from the actual closet to get to it. Pro, though, is that it won't freeze! Their water has less sediment in it than ours does, so hopefully no need to drain it. However, before we move in, I think we might really inspect it and consider draining and refilling it just to check for sediment first.

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In my parent's new house, it is located in a dedicated hall closet. It is LP gas and has pipes running into the attic for air circulation. A drain was put in before the slab was poured and only tile is used in that area. All fixtures have been equipped with gas and electric hookups. With their plumbing/gas/electric setup, this made the most sense as far as location.

I suppose the maintenance issue may vary on location but I have never drained a hot water heater. I've replaced one in my life. I can't imagine a water tank just sitting outside a house but maybe that exists. I can't imagine it would be up to modern code. Now a tankless that is supposed to be outside is a different animal.

If you are just talking about along exterior wall with access to outside, I can't imagine freezing is really an issue. The area should be insulated and still in conditioned space (even if there is no vent). The hot water heater will keep things warm enough to prevent freezing in most situations - if it isn't then you have far too little insulation. The number one issue for hot water placement in my mind is distance to fixtures and that should always be considered.

DavidCary addressed my thought: how inconvenient will replacement be? (Being quite a bit older than DC, I've gone through replacement issues several times.) In that time only one tank was drained for upkeep, and that was an old model in a hard-water, high sediment area. After the first time, there was very little sediment. Nowadays, I just don't bother with that chore, but if you do live in a high-sediment area then annual draining will increase efficiency and possibly lengthen the life of the heating elements. Hot water tanks seem to be consistent in lasting X-number years, which in my experience is their warranty-life plus a few months, lol.

I would be more concerned about possible leakage. Luckily, I've never had that problem, but I know several who have and it can cause an expensive mess.

If the closet is not sufficiently insulated to protect incoming waterpipes from freezing, then you will be paying an unnecessary extra amount to maintain the tank's water temperature whenever the closet is colder than the desired temperature. Fortunately, the remedy is quite inexpensive: add insulation! Use a "tank jacket" at the least, and best would be to insulate all sides of the closet including the below the flooring.

meldy_nva - On the one we had to replace, it was really probably just the element that needed replacing. (Or at least that was going to be the first thing to try.) Unfortunately, there was no way to remove it.

We were a bit confused when we started draining it as we thought there would be more water in it. The sediment was solid up to above where the bottom element was inserted. Basically tore up the unit trying to get it out. After we removed the old water heater and had it over on its side, some of the sediment fell down so we were able to get the element the rest of the way out and use a flash light to look at the inside a bit. Yuck.

Idea now is to drain periodically so that the element could be replaced if needed as a much cheaper thing to check for before replacing the entire unit.

No idea how old the original unit was. We had probably been in the house about 5 years and the house was about 5 years old when we bought it. Could have been that the entire thing needed replacing no matter what, but we weren't even able to attempt changing out the element.

**Have I mentioned I can't wait to get far away from this community well!**

We do have a water heater blanket on the unit.

Before I replumb my home with copper (built with galvanized pipe originally) I heard I should move my water heater on the outside of my home and place it where the two bathrooms (back to back) are near - the reasoning is that a gas water heater uses a lot of fresh air from inside the house, if it burst/ruptured/leaked - now it it outside and up on a stand with a box surrounding it - does it really make a difference inside or out? I live in Southern California so freezing is never an issue...