How to Install a New Toilet | Ask This Old House

This Old House plumbing and heating expert Richard Trethewey heads to Cheyenne, Wyoming, to help a homeowner install a new toilet.

Shopping List for Installing a New Toilet:

Tools List for Installing a New Toilet:

Steps for Installing a New Toilet:
1. Turn off the water at the meter.
2. Open all faucets on the upper level of the house, then open the tub or shower valve in the bathroom where you're installing the toilet.
3. Use emery cloth to buff clean the copper pipe stub-out protruding from the wall.
4. Put a shallow pan or a small bucket under the pipe stub-out to catch any water.
5. Use a tubing cutter to cut the pipe stub-out to the proper length.
6. Slip a new shutoff valve onto the pipe stub-out, then tighten the compression fitting with two adjustable wrenches.
7. Close all the faucets and valves opened in Step 2.
8. Turn the water back on at the meter.
9. Temporarily plug the toilet's PVC drainpipe with a rag to block out sewer gases.
10. Trim the PVC drainpipe to the proper height using a drill/driver fitted with an internal pipe cutter.
11. Use a hammer and a cold chisel to chip away any excess thinset mortar from around drainpipe.
12. Glue a new closet flange onto the drainpipe with PVC primer and cement, then insert two closet bolts into the slots in the flange.
13. Drill through the mounting holes in the flange and into the ceramic tile with a carbide-tip masonry bit.
14. Secure the flange to the floor with masonry screws.
15. Bolt the toilet tank to the toilet bowl, making sure to install the included rubber gasket between the two parts.
16. Attach the toilet seat to the toilet bowl with the two included plastic bolts.
17. Press a wax toilet ring onto the closet flange, then remove the rag from the drainpipe.
18. Set the toilet over the closet bolts protruding from the flange. Press down on the toilet to compress the wax ring.
19. Place the washers and nuts onto each closet bolt and alternately tighten each nut with a wrench. Do not overtighten the nuts.
20. Use a mini hacksaw to trim each bolt.
21. Snap the included plastic cap onto each closet bolt.
22. Tighten one end of a stainless-steel water-supply line to the shutoff valve. Connect the other end to the fitting on the underside of the toilet tank.
23. Open the shutoff valve to fill the toilet tank with water.
24. Put the lid on the tank, then flush the toilet to check your work.

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How to Install a New Toilet | Ask This Old House

[BOSS_]

Would have left the length of copper coming out of the wall slightly bit longer so that in the future if a plumber goes to change that compression valve they can do so without having to go into the wall because the previous valve deformed the pipe and made it now too short for a new one ✅

[ruelsmith]

When I install the Johnny bolts to mount the toilet, I use a sharpie and mark a line on the top edge of the bolts perpendicular to the T in the t-style Johnny bolts. That way, I can be sure the bolts haven't rotated around where the narrow part lines up with the flange slot causing it to pop out easily when tightening the flange nuts. It's frustrating when they do that and you have to pull the toilet to reset them. A little prevention saves a lot of headache.

[GuitarMastaDave]

The way he says "that's awesome" is so hilarious!

[joshcowart]

I always cut stub outs long enough so that I have access to the ferrule or brass ring in case i need to cut it off in the future. Basically add the width of the nut to the length. I’d also recommend using a stainless steel flange. For on me it’s much stronger. That plastic will break easily. For two, you can glue it and still spin the ring to where you want it so it’s much more forgiving

[CougarLand]

He cuts the drain pipe down below the finished flooring so it works with the particular flange he used.  Once you cut it off you don't get that back again in case things change in the future.  Another option is to cut it off flush with the finished floor and use a push-in (or push-tite) flange instead that fits inside the drain...some have a gasket and some are glued in. This also would mean he wouldn't have to remove any material from around the pipe like he did.

[TheRealKirkHammett]

I thought I had seen most tools in my life as an electrician. But that internal piep cutting drill attachment is pretty nice.

[faucettscience]

I love how he makes the guy he's teaching lift the toilet lol

[gordbaker]

I would leave the Maximum of supply pipe. You are now screwed if that connection leaks or you need to change that valve. 9 and '3'. Tighten Tank and toilet evenly. Turn on water before connecting to toilet and check. The plastic retaining nuts become brittle over time and can slowly or suddenly fail. I put a Rad Clamp around them and tighten it snugly.

[ProplumberbrisbaneAu]

As a Professional Plumber, i really like the way that you have presented in this video. Thanks for the good work.

[tvegas]

The ending was great. He flushes the toilet “That’s Awesome “ lol 😂

[dada]

Taking a dump is 10 times more satisfying when you know you've personally installed the toilet you're sitting on...

[mublikbublik]

Many here complained about a toilet water supply line cut too short. A way to avoid this and to make life easier for a homeowner down the road is to solder a male adapter to it and use not a compression valve but a FPT valve (female thread). That way if it ever needs to be replaced, it's easy and painless.

[JoeDianaHughes]

Great work, but that copper pipe was cut so short, next time you need to do work on it, you are not going to have any room left to cut it down if needed.

[sfbnnncmv]

Brian's "That's Awesome" shirts 👕 coming soon 👍🏼

[singalen]

Please file off the sharp edges after you cut off the excess length of the bolts. You might never come back again, but someone who will service it may get a nasty unhealthy cuts on their fingers.

[bobwoerner]

should mention remembering to remove the rag you put in the sewer pipe

[leesuschrist]

So when that shutoff valve goes, you'll have to cut into the drywall, replace the whole section of pipe, patch the hole, apply knockdown texture, prime and paint. All because you didn't wanna leave an extra half inch of pipe sticking out of the wall. Smart.

[Apathy_]

I like how ol boy came in there hot and excited to get that first flush. Probably sitting outside the bathroom biting his nails in anticipation of that woosh.

[aharvey]

Thank you so much for this video it was very helpful to replace my old toilet with no problem!

[JayZoop]

You have to be careful when tightening the water line to the tank. Sometimes the mechanism inside the tank will twist on you.