Plumbing: Replacing a Toilet

There are many reasons to replace a toilet. An old one might have worn-out internal workings that can’t be replaced, or it might be cracked, leaky, noisy, out of style or using too much water. Even if you’ve never replaced a toilet before, don’t be afraid to tackle this job. Few tools are needed arid it’s a pretty straight forward job, unless you run into stub born pipes, fittings or bolts.

One complication frequently accompanies a toilet replacement project—the floor. The floor beneath your toilet may be waterlogged or rotted, meaning you may need to replace or patch the finished floor and at least part of the one or two layers of plywood and floorboards below. Even if your floor is sound, there’s a chance the new toilet base won’t match, or even cover, the profile left by the old toilet base. Again, new flooring or patchwork will be required.

Here are some tips to help the installation go smoothly:

  • Before going to work, have the new toilet at hand, as well as a new wax ring, supply line, shutoff valve, if necessary, and two sets of new flange bolts and nuts (you can use the extra flange nuts and washers to firmly hold the bolts while you set the new toilet).
  • Don’t be tempted to stack wax rings to make up a height difference caused by a higher new floor. Instead, install or stack plastic flange extenders and use a single wax ring with a rubber flange that helps direct waste.
  • The simplest way to set the new wax ring is to simply sit on the toilet.
1. Empty the bowl and tank of water. To lighten the load, disconnect the tank from the bowl (usually held by two bolts). Unscrew flange nuts securing toilet to floor, If flange nuts spin, use a hacksaw to cut bolts below the nuts. Lift toilet off bolts and floor.

2. Replace any rotted subfloor. You’ll likely have to split new subfloor to go around toilet flange. Support all plywood edges with 2x4s under split and where old and new subfloor meet. Screw down new subfloor. Patch or replace floor covering.

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Recommended Reading

Composting Toilet System Book: A Practical Guide to Choosing, Planning and Maintaining Composting Toilet Systems

Book Description:

This book focuses on composting toilets (also known as dry, waterless and biological toilets and non-liquid saturated systems) because, among wastewater treatment technologies, they are one of the most direct ways to avoid pollution and conserve water and resources.

I'm Carol Steinfeld, a writer of books and articles about ecological solutions to threats to environmental and public health (they're really the same thing). Because words and ideas are never enough, I also conduct workshops on composting and how to make ecological toilets and wastewater systems. I also import some hard-to-find gizmoes for making all of that easier. Much of my work is about reporting on various systems, how they work, what they're like to live with, so I'm counting on feedback from readers to let me know what's working for them!

Issues covered:

toilet system book, composting toilet systems, urine composter, composted human excrement, solar pasteurizer, composted human waste, drying toilets, urine diversion, batch composter, toilet chute, central wastewater treatment plants, ecological sanitation, graywater system, composting microbes, leachate drains, evapotranspiration beds, excess leachate, septage hauler, composting reactor, squat plates, soil absorption system, toilet stool, composting mass, composting organisms, composting toilets.


The Definitive Composting Toilet Book: Del Porto's book is the definitive composting toilet book at this time. There is nothing even close. His book covers all aspects of composting toilet systems and touches on graywater issues as well. He treats the composting toilet as part of the home system. If a person is seriously interested in installing/having a composting toilet, this guide can save him/her all of the mistakes people usually make. He even (carefully) explodes some of the advertising myths that the purveyors of composting toilets would have us believe. The book covers ready-made systems as well as home built sytems. As trite as this sounds, the book truly is a must for someone considering intstalling composting toilet.

I would venture that the authors have forgotten more about toilets than most of the rest of us will ever know. There is no possible toilet configuration that does not receive at least cursory discussion. I only have 2 complaints about the book, both of them minor. First there were a couple of systems that I felt were described incompletely and critiqued a bit unfairly. Second, much of the book seemed to be a compilation of other writings without a lot of editing. Consequently there is significant repetition, and a presentation of information that's sometimes slightly disorganized and confusing.

Most complete and credible book on the topic: After reading a couple of books about composting toilets and graywater systems that were either suspiciously poetic or a little too humorous, I was happy to find this guide.
As someone who needs a variety of systems for a variety of high-use sites, I was glad to find a book that deals with this topic in technically and responsibly (in terms of public health). I showed this guide to my local health agent, and he was far more amenable to permiting an "experimental system" afterwards, saving me a lot of money.

Also, after experimenting with various systems over the years, I am aware that some systems still described in books and magazines just don't work well. The authors of this guide have apparently had the same experience, and I appreciate their researching this so completely.

Impressive, comprehensive, reader friendly, practical: The Composting Toilet System Book is an impressive, comprehensive, reader friendly, and practical guide to choosing, planning and maintaining composting toilet systems for those seeking an alternative to traditional sewer and septic tank systems. David Del Porto and Carol Steinfeld collaborate to explain the technologies, sources, applications, graywater issues, and regulations relevant to a composting toilet system for the home, whether manufactured or site-built. Highly recommended.

This is a great book to read while your sitting on the pot: This book was well worth the wait. Whether you want to buy a system, or build one, if it's not covered in this guide, then chances are it doesn't exist. It covers wet and dry toilets, self-contained composters and also cental units. What I like about this guide is that it discusses the pros and cons of each type of design in a very straight forward manner. The authors did a very nice job on this guide. If you ever plan on, or are even thinking about a compost toilet system, buy this one now. I leave my copy on my coffee table for guests, it always stirs up a conversation. No sh_t....

Recommended Products

EZ Rise Cushioned Toilet Seat 4 IN

EZ Rise Cushioned Toilet Seat 4 IN

Cushioned Toilet Seat distributes weight evenly so you can sit comfortably. Secures with straps to standard size 16" seats; available in 2" or 4" thickness. Makes it easier to sit and rise for those suffering with knee or back pain. Vinyl over foam wipes clean.

AquaOne FlowManager Toilet Overflow Water Leak Detection Devices

AquaOne FlowManager Toilet Overflow Water Leak Detection Devices

Discover peace of mind and save money on your home or institution insurance bills, water bills, and plumbing bills with the purchase and installation of the FlowManager Toilet Overflow and Leak Control System by AquaManagers.

Mariner II High Efficiency Toilet (HET) Elongated Pressure Assist Water Closet - 6203.420

Mariner II High Efficiency Toilet (HET) Elongated Pressure Assist Water Closet - 6203.420

(By:-Eclipse by St. Thomas) Elongated enhanced height pressure assist water closet combination 12 in rough 1 0 gpf / 4 0 lpf Chrome plated plastic tank lever supplied seat not included Click Here for Toilet Seats

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3. Screw toilet flange to subfloor with 2-in. brass or stainless-steel screws. If new flooring will raise finished floor height 1/2 in. (6 mm) or more, add flange extenders before screwing down flange. Install new flooring tight to the existing flange.

4. Install new flange bolts in flange. Stick new wax ring on bottom of toilet. Set toilet by lining up flange bolts with toilet base holes. Push toilet down or sit on it to set wax ring. Install washers and nuts on flange bolts.

5. Bolt tank onto bowl with new bolts and washers. Tighten cautiously to avoid cracking the porcelain and to keep tank level. Tank installation varies by manufacturer, so follow directions included with your toilet.

6. Install new no-burst supply line and , if necessary, new shutoff valve. Attach supply line to toilet tank. Turn on water and flush a few times. Check for leaks around water supply, tank-to-bowl connection and base.

Last modified: Friday, 2020-02-28 9:33 PST