Wow! New construction and the architect is spec'ing a 80 gal electric resistance heater? Really? Did he also suggest harvest gold appliances?

How about a hybrid electric heater that costs less than a gas tankless to operate and plays well with Solar PV.

Thanks, @Jake The Wonderdog -- what hybrid would you recommend?

Look at The Rheem hybrid.

80 gallon is a bit big for electric resistance in that size household. For hybrid, that size makes more sense. I have the 80 gallon Rheem hybrid. The wi-fi is problematic but the hot water isn't. Costs about $80 a year to run for our 3 person household (best I can tell). Resistance would typically be about $300.

Got about $2k from our utility too when put in a new home as part of a high efficiency home package (total was about $7k). Talk about a no brainer on a program that probably less than 1% of builders know about. You probably don't have such a thing but worth a check.

Kind of sad that your builder and architect are so antiquated. I was just at a friend's new house at the NC coast and on the ground floor was an electric resistance HW heater. The location was absolutely a zero issue with noise and also generally warm. Really ridiculous.

The hybrid hot water heaters of 10 years ago apparently had reliability issues but today they are fine. I have 2 trouble free models - one 3 years old, the other is 6 (in a rental house).

Thanks @David Cary. I should clarify that the architect mentioned the Marathon over 3 years ago when we started our project, and the builder is just getting quotes based on what we were thinking was the best option based on what the arch had talked about. I'm asking him to quote the hybrid as well. 100% case of "you don't know what you don't know" so I'm glad I'm asking about options!

+1 on a hybrid water heater. My old condo was a LEED certified gold home and came with a Rheem hybrid water heater located in the garage. In 6.5 years I never had an issue with it, always keeping it in heat-pump-only mode. If the temps dropped into the 30's, I could notice the water wasn't quite as hot, but I never felt the need to switch it over to hybrid or electric-only mode. The one time I used hybrid mode was when I had 6 house guests for Christmas and wanted to be sure everyone had hot showers. Considering your home is in CO, you may need to use hybrid mode more often with lower temps, depending on where the water heater is located. I think the newer models may switch automatically now (mine was manual).

Our new concern is the noise. How noisy, and how often noisy are they? Our current house is poured concrete, prestressed concrete floors and impact glass -- it's QUIET in here! And we both work in the audio industry -- noise would really bother us. How noticeable is the fan noise?

We have it above the master bedroom and can't hear it. It is louder than a subzero but probably not all fridges. Our outdoor heat pump is noisier (although barely audible inside). Where is it related to living area?

But everyone has different standards. Does your fridge noise bother you?

In the rental, it is in the garage and we can hear in the attached kitchen but there is a door with glass between the two and it is a 1983 house. It isn't objectionable - certainly quieter than the fridge.

There must be dB ratings somewhere.

I saw a youtube video that claimed it was about 65 dB, but it was measured with a phone, not an SPL meter. Our fridge (Monogram in current home) doesn't bother us, but it doesn't run often unless we're opening it up. When it does a defrost cycle, it is a bit loud for my tastes.

This well be located in the basement, under the foyer, in the center of the house. Quite a distance from the master, but only a stairwell away from my DB's office and one room away from my office, all one flight up from the mech room.

One more question... I understand that electric resistance heaters are old technology, but with a highly insulated version like the Rheem Marathon, what makes it so antiquated that it shouldn't be considered? We're a small household who practices water conservation -- turning water on/off while shampooing, etc. In calculating our needs, it seems like it will take 9 years for the extra cost of the hybrid to pay off. The hybrids look interesting, but certainly more complex.

@David Cary luckily, we've got a pretty good understanding of acoustics, so we're good on that.

If you only have two adults, you can easily use the 50 gal. (about $1,700) unless you have a large soaking tub. I'm not sure why an 80 gal was spec'ed.

The difference between a 50 gal Marathon and a 50 gal Hybrid is $500 before rebate. Using the DOE sticker - the Hybrid would save $280 a year and pay back in two years. Again - before rebate. The federal tax credit is $300 and If your power company is XCelEnergy - that water heater qualifies for a $600 rebate. There is a 180% payback on the difference in cost in rebates and tax credits alone (or you could spring for the 80 gal and still have the difference paid for in rebates and tax credits). ExcelEnergy will cut another $25 a year if you let them load control the heater. Your mileage may vary, depending on hot water use and electric rates.

And then there's that nasty little thing called climate change.

We won't have a large tub, but we will have a 43-gallon tub. I'll ask about sizing down to 50.

We are trying to simplify the house, and we think that an old-school heater is just less to break, less to maintain, etc. We currently live in Florida, on the ocean, so air conditioners and compressors are a continual maintenance concern that we would like to minimize in the new build.

We do understand climate change, but as I mentioned, we're quite conservative in our usage as it is.

Florida with a basement? On the ocean? That sounds unusual. Note that a heat pump hot water heater will dehumidify and cool the space it is in. You may not want the cooling but will appreciate the dehumidification. In florida, a garage is a really good place. But inside the envelope - but maybe not the basement - is even better.

I too had the same concern about reliability and it is why I have a resistance tank on a rental property on the coast built in 2010.

Remember, the hybrids have resistance built in so will continue to work as a dumb unit if the compressor fails. The early units (when I researched in 2010) were using poor quality compressors - from my understanding - window unit compressors.

The new ones are reportedly (and to my experience) much better.

I too have an efficient household and we were in a study - I think our true usage was 30% of DOE numbers so you should probably discount the savings by 50% as a starting point. The other issue is that DOE numbers aren't for FL specifically (warm ground water) and probably don't account for efficient DW and Washers. And, of course, it isn't all about the benjamins.

@David Cary I'm sorry -- we live currently in Florida, building in Colorado!