musingsheader image

Domestic Hot Water: No Perfect Solution

Gas or electric? Tank-style or tankless? It’s complicated.

Posted on May 13 2016 by Martin Holladay

Some questions are easier to answer than others. For example, there is a fairly straightforward answer to, “How should I insulate the floor of my unconditioned attic?” — namely, “With a deep layer of cellulose.” (There’s more to say on the topic, of course — but even a full answer isn’t very complicated.)

There is no easy answer, however, to, “How should I heat my domestic hot water?” Every type of water heating technology is flawed; every solution involves compromise.

Many factors affect the decision about what type of water heater to choose, including:

Tags: , , , , , ,

energy-solutionsheader image

Hybrid Water Heaters

A relatively new type of water heater combines features of both tankless and storage water heaters

Posted on Sep 13 2012 by Alex Wilson

In last week’s blog I compared tankless and storage water heaters and explained why tankless water heaters often don’t make that much sense.

Tags: , , , , , ,

Image Credits:

  1. A. O. Smith
  2. Grand Hall

energy-solutionsheader image

The Difference Between Storage and Tankless Water Heaters

While offering higher efficiency, tankless water heaters usually don't make sense

Posted on Sep 6 2012 by Alex Wilson

There are two primary types of water heaters: storage and tankless. In this column I’ll try to explain the differences between these two approaches and offer some guidance on choosing between them. (There are also “hybrid” water heaters with features of both that I’ll cover in a future blog.)

Storage water heaters

Most water heaters are storage models. These are insulated tanks holding 20 to 120 gallons with either electric heating elements or gas burners. The storage tank stratifies with hot water at the top and cold incoming water at the bottom, so that as you draw off hot water (from the top), you get consistently hot water until the hot water is nearly depleted. The “first-hour rating” tells you how many gallons of hot water can be delivered in an hour. 

Tags: , , , , , ,

Image Credits:

  1. Rheem Water Heating

musingsheader image

Are Tankless Water Heaters a Waste of Money?

The energy savings you’ll get from a tankless water heater are usually too low to justify the high purchase price

Posted on Apr 6 2012 by Martin Holladay

Although tankless water heaters are, on average, more efficient than traditional tank-style water heaters, they’re also more expensive — so expensive, in fact, that many potential customers wonder whether their high cost can ever be justified by likely energy savings.

Tags: , , , , , ,

Image Credits:

  1. John Eisenschenk

green-building-curmudgeonheader image

Evolving Opinions on Green Building

The enduring value of spray foam, fiber-cement siding, PEX tubing, and other ‘green’ products

Posted on Mar 21 2012 by Carl Seville

I still remember using spray foam insulation in my early green renovation projects – it was almost magic! It sealed and insulated in one shot. It made it easy to finish attics and avoid most of the problems with fiberglass batts that were the common insulation on our jobs.

Tags: , , , , , , , , , , , , ,

green-building-blogheader image

Stuff I Learned at Joe Lstiburek’s House, Part 1

Everything I thought I knew about combined hydronic heat and hot water (combo) systems utilizing tankless water heaters is up for debate

Posted on Aug 10 2011 by Michael Chandler

The invitation was too cool to be real: My name was somehow on a list of “experts” who were invited to take part in a Building America Water Heater Expert Session on combo systems. The invite noted that the session was to be the day before Joe Lstiburek’s Building Science Summer Camp, and “it is expected that the information obtained will lend itself toward the eventual production of a guide for the best practice application of combination space and domestic water heating systems for new and retrofit residential construction.”

Tags: , , , , , ,

Image Credits:

  1. M. Chandler
  2. Armando Cobo
  3. Rheem.com, DHGate.com

energy-solutionsheader image

Storage vs. Tankless Water Heaters

Posted on Jun 2 2009 by Alex Wilson

Last week I suggested some ways to reduce your hot water use. This is almost always the easiest way to save energy with water heating—it’s the “low-hanging fruit” to be sure. Over the next few weeks, I’ll get into water heating options. To start, let’s look at the differences between “storage” and “tankless” water heaters.

Tags: , ,

Image Credits:

  1. Paddy Morrissey, Code Check Building 2nd Edition

Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!

Syndicate content