Q: My wife and I are in a disagreement over the new toilet we plan to purchase. We both want to install a high-efficiency toilet, but we have not decided on the flushing system.

I would like a dual-flush toilet, but my wife says she wants to keep it simple with a single-flush toilet. What is your opinion on this plumbing debate?

A: Super water-saving toilets are called high-efficiency toilets, or HETs for short. To qualify for HET status, a toilet needs to use less than 1.3 gallons per flush. (Standard toilets use 1.6 gpf.)

There are many high-efficiency flushing systems on the market, and two of the most popular types are the “gravity” single-flush and dual-flush models that you mentioned.

Single-lever flush systems are easier to operate since every flush is rated at 1.28 gpf. However, dual-lever flushing offers two choices, a “half flush” for liquids and a full 1.6 gallons for solids. This allows full flushing control, but dual-flush toilets also average about 1.28 gpf.

Since water-saving efficiency may be a washout, choosing can involve the area in the house where the toilet will be installed. For private bathrooms with one or two users, a dual-flush toilet can be a nice choice. For higher-traffic bathrooms, offering a single-flush choice may cut down on flushing confusion.

In my opinion, you don’t want your guests pressing the “No. 1” button when they should have pressed the “No. 2” button.

Master contractor/plumber Ed Del Grande is known internationally as the author of the book “Ed Del Grande’s House Call,” the host of TV and Internet shows, and a LEED green associate. For more information, visit eddelgrande.com.