Replies

1. GBA Editor
   Martin Holladay|Dec 31, 2013 08:05am|#1

   Federico,
   The most important principal of designing an efficient hot water distribution system is to locate your water heater near your hot water faucets. You might consider serving the hot water needs of your shower with a tankless gas water heater or a tankless electric water heater located close to the shower.

   For more information, see the following articles:

   Inefficient Hot Water Piping Layouts Waste Hot Water

   Waiting for Hot Water

   All About Water Heaters

   Efficient Plumbing Supply Layouts

   Point-of-Use Electric Tankless Water Heaters

2. 
   Keith H|Dec 31, 2013 10:20am|#2

   Is there something unusual about your building site that requires your water heater to be so distant from your point of use?

   If not, I'd say fix this design flaw now. If there is some site issue, please share it. Is there a subcontracted plumber or did the builder come up with this terrible idea all by himself?

   Are you using a conventional tanked water heater, a power vent, or a tankless? Gas or electric?

3. 
   Federico Feldstein|Dec 31, 2013 10:22am|#3

   Martin,
   Thank you for your answer!
   i am actually considering either tankless or two smaller systems, but what about running the hot water lines underground? is that efficient?

4. 
   Federico Feldstein|Dec 31, 2013 10:26am|#4

   Hi Keith,
   thanks for your answer. No, there is nothing unusual about the site. it's a slab on grade and the builder run the lines under the slab, but i am thinking that this can be solved by running the hot water line within the house envelope.

5. GBA Editor
   Martin Holladay|Dec 31, 2013 10:52am|#5

   Federico,
   It's possible to insulate buried water lines, but I don't recommend it. Even if the tubing is well insulated, the hot water line is much too long.

   You don't want to locate your water heater 50 feet away from your shower. The articles which I suggested you read explain why.

6. 
   David Meiland|Dec 31, 2013 11:17am|#6

   I agree, move the water heater much closer to the point of use, and/or add another unit. Keeping the hot water piping very short is key to saving water and energy, and avoiding long wait times at the fixture. Running the piping under the slab is not in itself a big problem, IMO. In a slab-on-grade house, sometimes the most direct run to the fixture is under the slab. Obviously you have to look at each case separately, but I would probably rather have a short run under a slab than a long run drilled through the framing all the way around the room.