Gas has faster recovery time than electric.

Can you install a solar water heating panel and use the gas/electric as backup?

We can't bust the budget with complicated systems. I've decided tankless is not practical for us. Recovery time is one concern. Electric doesn't require venting.

Russ first where are you located?

Also why did you decide tankless is not practical? Personally in any new build now, I wouldn't do anything but tankless.

I would do gas as the area I lived in had a horrible wind storm and many of my coworkers were without power for 10-14 days and having hot water made it manageable. Same goes for a furnace too.

We are building in Montana. 5,000 sqft 2 story house on a crawl space and a well. Natural gas furnace.

There will be 3 of us living here. Our son takes LONG HOT showers and there is not enough hot water after he's done. So it needs to be a big tank or perhaps 2 tanks.

My reasons for not using tankless hot water heater:

• The distance to the furthest bathroom would make it less than practical unless we added a heater just for that one bathroom. Mounting in crawl space would be a PITA. A recirc pump would solve that with a tank heater.
• Minerals in the well water. I've read build up on tankless is an issue.
• Consistent temperature and wait for hot. I've read with tankless, there is a delay until it start delivering hot to the tap and sometimes the temp is not a smooth consistent temperature. Our current house requires a 60 second wait for hot and this is a negative in my opinion. I don't want to deal with that this time.
• We will most likely need a water softener and I'm not sure tankless works well here.

--Russ

I'm going to catch a rasher of grief for this, but I'm going for an all electric house. Basically for simplicity, and I hate propane tanks, as well as trucks tearing up my gravel driveway. DH also asked for a system that's as quiet as possible, because he's recording music.

I'm looking at the Runtal electric radiators, and easyheat under tile. I had a water based radiant system last time, and it worked well, but it's complicated, with many expensive parts that have to be maintained and replaced. This time I thought, to heck with it. We may not be here much in the winter, anyway.

So the electric water heater will go under the stairs, no basement and no venting. We'll supplement the electricity with some solar and a backup diesel generator.

We went with 2 - 75 gallon gas (LP) water heaters, on a recirculating system with a built in timer. We have 5 in the house, and everyone loves a long, hot shower. Plus our master bathtub is close to 80 gallons.

Most importantly if you choose gas, do not choose an atmospherically vented model. Direct or power vented is the only way to go and think the more standard natural draft style venting will be made illegal in future building codes.

Combustion appliances inside the living space need to be done with care. Even properly vented and installed appliances increase risks to indoor air quality.

I agree that tankless are not always the best choice and I think it's better to avoid gas infrastructure altogether when building new.

Heat pump water heaters are an increasingly obvious first choice for heating water in most climates. They use electricity but are cost competitive in both upfront and operating costs to good gas units. Inside location can be a challenge and cold climates don't gain as much from their cooling with dehumidification benefits but they still make sense in cold climates for conditioned crawlspaces and basements. For mixed and warm climates, they are the best choice if you can find or design the right spot for one.

We will have a big soaker tub in the master bath also. However, it's mostly for show as I doubt we will ever use it as we will have a hot tub outside. However that is a concern.

--Russ

SB, Heat pumps don't work well in our climate. Geothermal is the solution here and we considered it, however the cost was $50k and we don't plan on being here more than 10 years and we're already busting budgets everywhere else.

The utility room is off the garage and will have a nat gas fired furnace there already.

--Russ

Certainly having gas infrastructure already, strengthens the case for gas heated water. With heat pump water heaters, the heat pump is attached to the water heater and located inside, so it doesn't have much to do with outdoor temps. It sounds like the utility off the garage may be the perfect location for a heat pump water heater.

It's true that typical space heating/cooling heat pumps, which do rely on outdoor temps, make less sense in cold climates but many high performance builders are using mini-split heat pumps in very cold climates like yours. Some models still squeeze heat from air as cold as -14 F, without electric resistance backup. At 5000 sqft however, a fully ducted system is probably the best way to go.

We contemplated radiant heat (possibly geothermal). Forced hot air it will be (2 furnaces, 4 zones total as we pushed the limits of one system).

Where do heat pump water heaters get their (heat)? The garage will be semi-heated (stand alone gas ceiling heater). However, pulling heat from there in the winter is essentially tapping the gas heated air isn't it?

Our builder does both electric and gas hot water. Electric is easier (no venting). I don't care about easy as much as best for us.

My biggest concern is having enough HW for all of us to shower and possibly recovery time if we burn it all filling a tub or something. I've nixed the tankless for above stated reason.

--Russ

Our plumber came very highly recommended, so when we did our walk-through with him, I asked him "If this were your house, what would you put in?".. Not sure that's an option for you, but it helped make our decision. He also showed us the same system he had just installed for his daughters new home.

My biggest concern is having enough HW for all of us to shower and possibly recovery time if we burn it all filling a tub or something. I've nixed the tankless for above stated reason.

I'm not understanding your comment about recovery time and tankless. Once the hot water starts flowing (and for us here in FL it's about 30-45 seconds) we have enough hot water to fill our 6' x 42" tub, take two hot showers, and run our washing machine on hot, while washing dishes. We can do that all at the same time, or one after the other. There is no recovery time because with tankless it's constant. The only downside is that if we were to run all of those at once, we'd have a small drop in water pressure, but not in hot water.

However, I do understand that tankless might not be as efficient in your climate.

Geothermal here with 2 80 gal electric. Love our geothermal.

Both of our water heaters have been replaced (under warranty). Plumbers say they don't make them like they used to.

cpartist,

I was referring to my comments in a post higher up about why tankless doesn't appeal to me. Tankless, by nature is an endless supply of hot water which his a plus.

My concern 2 posts above were with traditional tank systems and recovery time.

How far is your tap from the heater? I don't want to sound picky, but 45 seconds is a long time to wait for hot water. We do that now and it's annoying. Also, one of our bathrooms is 90' from the utility room which means it would need its own heater and the only place to install it is in the crawl space which doesn't appeal to me.

--Russ

CP..silly question. I wonder if tankless would be possible with geothermal. Nah...the geothermal helps heat the water. Wouldn't make sense.

Would love to have both.

we have a tankless under a bath vanity in our office and my dd loves it.

60 second wait for hot

Aggravating when you want to step right into a shower!

I insulate all supply pipes, hot and cold, to reduce noise. But the side benefit is that the initial water you get when turning on a tap is a comfortable lukewarm.

I did one new home with double electric tanks instead of gas fired. But that was only because I wanted the utility room in the centre of the basement and at that time high efficiency gas units were limited to 25' from an exterior wall. Even with the two tanks, morning showers for four and the two top-loading washers quickly drained both tanks.

Well, the kid could stop draining the tanks.

But really, our plumber said nobody installs tanks in new construction anymore. You can do a recirculation loop for tankless as well, and have instant hot everywhere.

I did not do the recirculation as I am not really bothered by the wait, as it is usually only once a day it starts from cold. But it does waste some water. And I suppose some might be annoyed...

Imo gas will be cheaper over time, but that is just a guess.

Recirculation can be tricky but worthwhile. Yet another expensive solution for poorly conceived or oversize floorplans and plumbing layouts. ECM/DC circulators, timer/motion/button demand with correct size plumbing trunks and branches offer better results. Not the kind of usual work done by most trades. Typical circulation setups usually make the water heater (2nd biggest home energy user) work hard.

Endless supply of hot water is a bad thing to me, a sure way to excessive waste. If 60-100 gallons can't serve your needs, a tiny amount of behavior change should solve the issue. Just bought my parents an 80 gallon Steibel Eltron accelera heat pump water heater. It boasts an Energy Star EF of 2.7 and a first hour rating of 76 gallons. Pricey upfront, but an excellent investment with a simple payback of 2-7 years while eliminating costs and risks of proper gas exhaust. It's also possible to eliminate or at least reduce dehumidifiers in crawlspaces or basements.

They do rob heat from interior spaces which makes placement extra important in cold climates. Spaces like semi-conditioned garages, crawlspaces and basements still have year round energy benefit in cold climates. In most climates, the cooling and dehumidification is highly beneficial.

The most affordable solution for the young tank drainer may be an up-to-date shower head. I'm guilty of it myself and been wanting to try the newer technology which supposedly offers better sprays at lower flows. I know of High Sierra and can't remember the better looking option I recently read about. Anyone?

Springtime the real benefit is you're not constantly having to heat 60-100 gallons of water with a tankless. You heat what you need, when you need it. Additionally, you don't need to worry about replacing a leaking water tank every 10 years or so.

I'm fairly certain you can no longer buy regular electric hot water heaters above 55 gallon tanks thanks to new energy efficiency standards.

As of April 16, water heaters must comply with new Department of Energy efficiency standards. The water heaters used in most homes won’t seem that different and will get a modest boost in efficiency, according to the American Council for an Energy-Efficient Economy. But larger units -- those 55 gallons or more -- will need to shift to new technologies to achieve the efficiency gains. Doing so can cut utility bills by 25 to 50 percent depending on the technology used.

I just replaced a 10 year old 80 gallon tank (just for energy efficiency, the water heater was working). I wanted a plain old electric but there were none available anywhere. I had to buy a hybrid heat pump style. The cheapest I could find for an 80 gallon was for a GE heat pump hybrid which was $1799 (not including installation). It seems to be working well to produce hot water but is LOUD!

I think that argument of tankless is mostly marketing hype. It suggests tankless saves more than tanks which isn't necessarily true. Including costs of gas infrastructure, monthly fees and venting, tankless can be a waste of money.

There's good reason for the DOE's push out of ridiculously crappy water heaters. It's low fruit and comes with indoor air concerns of combusted fossil fuels. This building green look at heat pump water heaters is helpful and can still recommend the AO Vortex and Geospring models.

Noise is a problem. They are improving and usually located in spaces where noise is less of a problem. Expect a bit louder than a fridge at this point with some models better than others. Even with noise complaints, I think heat pump water heater HPWH technology will eventually replace most tankless gas.

Durability is more dependent on the situation and I would expect heat pump water heaters to last longer than tankless gas more often than not, especially as HPWH become more standard. I value durability which is why I bought a Rheem Marathon around 8 years ago. If I could have waited until today's HPWH were available, I could be saving a lot of energy and probably eliminate the basement dehumidifier.

If we wouldn't neglect anode rod maintenance, tank heaters could last 50 years or more and I expect my Rheem tank is easily capable of that with it's no-anode-necessary design. Uh oh, did I just lock myself into 50 years of excessive energy use? Should I replace my aging dehumidifier or just buy a heat pump water heater? I suspect the better long term investment is the HPWH.

There's good reason for the DOE's push out of ridiculously crappy water heaters

Except not everyone can or wants to spend $2000+ to have a new 80 gallon hot water heater installed, which is now the minimum cost you're looking at if you need this size and have to use electric.

I agree. It's tough in the short term but will be better in the long term. A bigger, more painful version of incandescent light bulb phase out for better performing LED. I think some utility providers are offering payment plans. These measures will end up benefiting future inhabitants for the most part.

This may be a dumb question, but why couldn't you just install two 40-gallon electric water heaters, which even with new technology (e.g. energy sense) cost about $400 each?

I think you could... if you have the space. But you'd also have to factor adding an electrical hookup for the second water heater and added piping for the new heater...which may not be a problem w/ a new construction but is a bigger issue in an existing house I would think...

omelet

This may be a dumb question, but why couldn't you just install two 40-gallon electric water heaters, which even with new technology (e.g. energy sense) cost about $400 each?

Because when electricity prices go up, those savings will be eaten up far before their lifespan.

Ichabod, I wasn't referring to electric versus gas, but to the issue that was brought up related to replacing a large gallon water heater under the new regulations which are significantly different for WH >55 gallons.

My newly built home has 2 50gal gas water heaters, gas forced heater, gas cooktop, gas log fireplace.

Can I interest anyone in a stockpile of incandescent light bulbs and this nifty ventless gas fireplace?

Actually I love incandescents and I have a large stock pile and they can pry my incandescent light bulbs from my cold dead hands because I am never giving them up!

My Rinnai gas tankless water heater has a built in recirculation feature. My furthest bathroom is 50' from the tankless. The shower is hot within 8secs of turning it on. My recirculation pump is on a timer and is programmed based on my family behavior. I was really concerned after reading so many of the reviews online about tankless water heaters topics like temp sandwich and not being able to use multiple showers and appliances at the same time. I have low flow shower heads in my bathrooms from Grohe and Hansgrohe. Two of my bathrooms have thermostatic valves. The third has a very old pressure balance valve that will be replaced soon. The shower heads are rated at 2.5gpm. They perform really well. The tankless also has a feature to fill a bathtub,. I have used this once and the tankless worked like a champ and filled a 50gal tub in 9 mins. I have city water and will perform my first flush of the system in May. I was also afraid of the temperature drops as it got colder. We had a week of sub zero temps and I noticed no impact on the water heater. We can take two showers concurrently, run the dishwasher, washer and a faucet at the same time. My home has a crawl space and most of my plumbing runs through the crawl. The tankless unit is hanging on the wall in the utilities room.

Just wanted to post another experience in tankless. One of the main drivers for going with tankless in my case was that I needed the space. The tank heater blocked access into the utility room and a wall needed to be taken down to remove the heater. I have a Rinnai RUR98i.

Good luck!

If you think you are ever going to install a tankless, it is much easier to do when you are in new construction because they have very high power requirements. You need to prepare for this when your electrical is done.

So reading all the comments, I've gone back to do more research on tankless heaters.

Some do have recirc pumps, so that solves one problem.

Water softeners can resolve the scale build up concern with annual cleaning.

High efficiency models seem to allow inside mounting with powerventing via PVC type venting.

Sooooo...I'm now considering a nat gas tankless system.

During construction is the time to do this. Once walls are closed up, this option will go away.

--Russ

Have you thought of installing a hybrid electric water heater? We purchased this Hybrid electric water last week. Don't have it hooked up yet, but hoping for a lower electric bill ( we don't have gas available in our area) I believe they have it in an 80 gallon size also. It states that it is 67 percent more efficient than a regular electric water heater and you would be eligible for a tax credit.

Russ,

As I mentioned, my tankless was a retrofit. It took longer to remove the tank heater than to install the unit. It was super easy and mine used the PVC piping. My plumber installed it without a hitch. I purchased the Rinnai from Build.com. Mine is also mounted indoors. I did purchase Rinnai descaling kit in line with the water heater. I am looking to install a water filtration system on my incoming cold water line. I have been researching configurations of filters that will allow me to deliver 10gpm to the water heater as a minimum.

Regarding the gas line size, Rinnai uses the 0.75" gas inlets if I remember correctly. There are some models that allow you to use smaller gas inlets.

Good luck!

Good to see the prices of heat pump water heaters, like the Geospring hybrid MsLindley linked to, are falling in price faster than I thought. That is cheaper upfront than most good gas tanks or tankless, plus you avoid the costs of gas piping supply, combustion exhaust venting and potentially monthly service fees.

Not trying to talk OP out of tankless, just want others to realize that hybrid/HPWH are often a better choice financially, especially when replacing or reducing dehumidifier and AC usage. In many situations I think they use less energy too. That GE unit may be the best water heater available made in America.

People considering the economics should also look into any incentives from the electrical provider. They are pretty common around here.

I actually purchased this $999 water heater for $629 last weekend. (699 minus veterans discount) . They must have had a recent price increase. With the $150 tax credit, it is comparable in price to a regular electric water heater. I believe It pays for itself pretty fast.