How to Add a New Dishwasher to a Kitchen | This Old House

Hooking up a new appliance with This Old House plumbing and heating expert Richard Trethewey. See below for a shopping list and tools.)
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Shopping List for Adding a New Dishwasher to a Kitchen:
new dishwasher [amzn.to/34sIHxT]
three-way shut-off valve [amzn.to/2ZLlloR]
stainless steel braided hose [amzn.to/2UBM3dr]
dishwasher tailpiece [amzn.to/2N0dVHr]
teflon tape [amzn.to/2ZNLnCU]
polarized appliance plug [amzn.to/2LAHYSG]
electrical tape [amzn.to/2HRhH1x]
Tools List for Adding a New Dishwasher to a Kitchen:
adjustable wrench [amzn.to/2LoC0pr]
open-end wrench [amzn.to/2PRj1I0]
pliers [amzn.to/2LnfjSk]
drill/driver [amzn.to/2ZQS4nM]
canvas tarp [amzn.to/2MYcJ7h]
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How to Add a New Dishwasher to a Kitchen | This Old House
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[@BobbyBaloney]

Richard is the best : explains clearly, shows and educate brilliantly

[@fixmyhouse]

No background music. No graphics. No nonsense. Pure legit valuable information.

[@gordonweliky9179]

….and that’s why they’re the best. That, and Tom.

[@elka5768]

Would have liked to see the holes in the cabinet - how to drill them and where to put them... But the rest was good :)

[@MarzNet256]

E lka The install instructions that come with machine will tell you where to make the holes.

[@bcbock]

Usually near the bottom of the cabinet. Manual will tell you.

[@elka5768]

@@bcbock unfortunately "used" don't come with manuals

[@Mockduck2020]

As high as possible with a spade bit a little bigger than the fattest part of the drain hose.

[@dosadoodle]

2:10 - Not the topic of this video, but there's no p-trap on that sink. Is the trap somewhere else in the system? (I'm assuming that wouldn't meet modern code.)

[@traviswatson4986]

I isolate it and add another shutoff for the dishwasher. Those are notorious for problems and then you have to shut your sink down too. If you have renters add a shutoff for the unit

[@tessak5869]

Very helpful! Thank you!!

[@wolfplex1]

Thank you!!

[@vishwanpurandat8302]

Why not connect the supply to the washer first then tape it and slide it in?

[@andreyyaromich8277]

It’s easier to connect to washer first then feed the house through and pull it through as your pushing dishwasher in , just guide it gently as it’s going, this is overkill over-engineered process you see

[@MrG25AmunRa]

Buddy had the gangsta snap on those glasses 😂

[@grassballsss]

Lol

[@Shadow_wo1f05]

Plumber by day gangsta by night lol

[@M-X39462]

I came to the comments section immediately after seeing that 🤣

[@anthonymoore6250]

Right lmao. Then fuckers snap together loud

[@90qwertys]

@@M-X39462 same 😂😂😂

[@Legman688]

Is it just me, or did that sink not have a P-trap?

[@madgepins1967]

Yeah, I noticed that too. Weird

[@quartzofcourse]

No vent either, what is going on down there

[@colinjones4686]

Needs a trap with an aav.

[@shannoncrawford9900]

The trap is below the floor

[@rsomes]

Drum trap in basement guaranteed

[@philipscoggins]

Thanks! I just did this in my old house and out of all the internet, this video was the most helpful!!! I did hire a plumber to tap my old supply line, but I felt comfortable doing the rest myself. 👍

[@jayyoutube8790]

4:20.. Those glasses are pimp

[@kurtvonfricken6829]

You know things are getting real when Richard puts them on.

[@SzaboB33]

came here to learn about plumbing, left seeing the coolest glasses ever

[@jej3451]

4:18 cool magnetic glasses.

[@joeyoung2834]

I didn't know they made glasses like that.lol

[@GlitchedPepsi]

4:20

[@santosshernandezjr8553]

Does anybody notice there’s no p trap?

[@johnlehman4614]

Judging by sink/cabinets, house looks pretty old. Would guess a whole house cast iron p trap in the basement

[@jacksplumbingvideos7147]

The p trap is in the basement

[@jerzsubbie]

Smooth to black, ribbed to white, exactly what I was looking for, thanks!!

[@joblessalex]

jerzsubbie it doesn't matter one bit. It's ac.

[@SamMcWhannel]

It's matters for safety reasons. Typically the hot is switched not the neutral so when things are turned off they are also de-energized. The neutral is ground referenced so it's unlikely to give you a shock. If you reverse the polarity, all the parts in the appliance will remain live at 120v even when off.

[@ronshatilla9370]

You could also follow each wire back to the plug and see which side is the smaller prong. Smaller prong = hot

[@bjornjoseph]

Lol I traced the wire... since right side is hot

[@on4acres]

You can also plug it in to an outlet and use a voltage tester to see which wire is hot.

[@ChieCarroll]

Just watched this, so helpful! We got a quote to install the dishwasher under our sink that has never had any dishwasher. Unfortunately, the charge was too high that we can't afford it. So I sure hope we could follow this, it looks so simple and easy to follow and install the coming dishwasher 🙏😊🤪

[@AStanton1966]

Remember what the 3 Stooges said, "Who says you have to be smart to be a plumber?"

[@aaronbaraiya3692]

​@@AStanton1966 I love those guys

[@MsCharae23]

Did you do it?

[@Brad1962Fisher]

Why doesn't the sink drain have a water trap for sewer gas?

[@heystarfish100]

Richard wouldn't make that mistake so it must be somewhere down below. Maybe the explanation was edited out? Weird plumbing if you ask me.

[@bmanwpg]

Was thinking the exact same thing myself. It was missing when they started, but didn't add one in when they retrofitted... wonder why.

[@Chuck59ish]

It's probably in the basement, just below the floor.

[@erictold]

A drum trap was located in the basement; see 13:00min in full episode. If you put a P-trap again under the sink, it becomes S-trap which is not acceptable per code.

[@Brad1962Fisher]

ok

[@Watch-Me-Now]

Where’s the P-trap for this sink?

[@xxjusxstarxx]

Some old houses have an entire house ptrap instead

[@Watch-Me-Now]

@@xxjusxstarxx My point was that Rich being a master plumber, should’ve commented about it not having a P-trap or explained why it didn’t need one, if that’s the case.

[@xxjusxstarxx]

@@Watch-Me-Nowthat's a valid point

[@billsmith9249]

I've said it before, but wow! What a wealth of knowledge and experience that the pro's on TOH possess! Not only are they incredibly gifted in their fields but they also have tremendous charm and personality! Thank you to all of the pro's and to TOH!

[@noontide1209]

4:23. Boss has magnetic glasses

[@proverbsjohnson7594]

So our home was built in 1928. It still has all original woodwork and cabinets (which is why I fell in love with it) but no dishwasher. Being the mom of 4, and having to work and take care of home I realize how much I truly miss having a dishwasher. Thank you for this video. Great job!

[@Pro1er]

They make portable dishwashers my parents bought one 60 years ago. kzbin.info/www/bejne/mp2QnZ54rqxlhpY

[@holeshot1721]

This was a great episode! Im so thankful great people take time to make these videos for us!!

[@add422123456789]

This video was perfect just what i needed!

[@george-101]

I'm surprised that Richard didn't add the water trap for the sink, the pvc just did a 90 degree with no water trap. Great video though, love this show

[@lcaunan]

There is no P trap. Did Richard mention anything about that?

[@TortureBot]

He didn't mention it in this video. But there's a good chance there's a basement under this home, so there's an easy to access area where they may have put a trap underneath the floor between the floor joists similar to what's under a shower or tub. Hopefully!!!

[@brendonh91]

Where's the vent and p trap for the kitchen sink 🤔

[@cristianrizo3568]

Exactly what I said

[@jacksplumbingvideos7147]

The p trap is in the basement

[@leoc5738]

Good video. Would have been nice to see how to hollow out the cabinet though

[@plumbingstuffinoregon2471]

I noticed that there's no trap under the sink. Is there one under the floor or something like that?

[@Bremend]

I noticed that too, I have an atmospheric vent instead of a roof vent for mine

[@bcbock]

Presumably the drain pipe terminates in a p-trap to a vented stack in the basement, just like bathtubs, showers, and toilets do.

[@JamesJones-ie2fm]

Very good how to. Learned a lot by watching it, don't think I'll need a plumber to install my new one after watching this.

[@Neil-teamBrigade]

This chap has a soothing voice. Could teach me stuff all day long.

[@jpay]

5:43 when you go for the fist bump but they're just not feeling it.

[@mikegruber172]

lol

[@-007-2]

i think he was going to point to the electrical box but bailed because she was already on it.

[@c0mputer]

He was just pointing at the outlet saying to plug it in. And Besides, Tommy is the fist bump guy.

[@kennyg3192]

My thing is without a trap, proper venting and a dishwasher. Where is it venting to? Where is the vent at? Where is the trap at? Is it hidden from me cause I’ve seen him say it is very important to have a trap on your sink and plenty of videos it’s a code. It ain’t like a standing shower to where is though you can run your 90 out of your standpipe and put your trap near your trunk line like they do over west coast but here on the East Coast we try to keep our traps within the tailpieceunless engineered or specifically specified by an inspector and people got to stop buying things from Home Depot thinking because they sell it that it’s good that’s not always true

[@joshuamartinez2444]

Dang I have had a dishwasher in my mud room since 2013. Still not installed. I’m showing my husband this video

[@spockmcoyissmart961]

Why rush things.

[@bcbock]

Or do it yourself.

[@geojor]

excellent educational video, thanks...

[@tashtant]

I noticed there was not P trap under the sink, is it installed under the floor or was it missing?

[@kylecurkan2825]

Some particularly old houses have a single large P trap for the entire house, that is my guess.

[@The_honoured]

Thanks a ton, after this video I installed my new dishwasher myself.

[@MMGJ10]

"How to add a dishwasher to your kitchen". I just left a trail of Reese's cups, and Dove chocolate to the kitchen sink for the old lady and let things sort themselves out.

[@88blackandwhite88]

Excellent video. I love seeing demonstrations done the RIGHT way. Well done!

[@lolahunter8851]

Done the right way? Not sure what third world plumbing code this guy is working to doing an installation on a sink without a p-trap? NOT!!!

[@FamilyChannelfun32]

Where's the trap for kitchen sink

[@robertlinkonisjr.2577]

I know right wtf

[@breidyhernandez9263]

I wonder the same thing. Where is the p- trap for the kitchen sink

[@peppeddu]

Gotta be somewhere otherwise she would have the kitchen filled with a nasty smell

[@steakwilliams4448]

It's likely in the crawl

[@timtaffinder]

it's probably in the basement

[@paulgrieger8182]

Wait! Why isn't there an "S" trap on that sink drain pipe?

[@TVCanT]

Where's the 'P-trap'?

[@jeffreypedler8845]

Looks like the hose from the dishwasher connects to the sinks tailpipe, which has a pee trap.

[@garychambers5930]

@@jeffreypedler8845 he's talking about the P-trap off the sink Hopefully it's in the basement

[@guitar1301]

P-trap cannot be in the basement as per code on kitchen sink

[@jackielinde7568]

The house looks like it was built before the code for p-traps were in place. It's not hard to install one, but the homeowner will need an extension on the tail piece. I don't know why Richard didn't suggest adding one. But, I shan't question his judgement. Also watching the hot water supply bounce up and down was a little scary.

[@conqwiztadore2213]

Maybe the have old style "building trap" outside the house 😂

[@shurryma]

This was so well explained. Thank you!

[@Maverick-2202]

no trap???

[@tighecrovetti2844]

@Pyroman / except there isn't a trap for the sink....that's what he's saying

[@andreyyaromich8277]

The trap is already installed under the sink, (under the floor) those Elbows are just offsets you are allowed to have above a ptrap.

[@jacksplumbingvideos7147]

The p trap is in the basement

[@georgiaflyer8702]

Why no trap on the sink?

[@MarzNet256]

Georgia Flyer There is (or should be) a whole house trap in the basement. One trap for all the drains in the house.

[@georgiaflyer8702]

MarzNet256 thanks!

[@roadtripray]

I have never seen that before.

[@jonhipolito807]

@@MarzNet256 then they should have used 1/8 bend for easy flow

[@johnkrim8377]

No such thing as one trap for whole house , every fixture is supposed to have its own trap. House trap has nothing to do with being the trap for the individual fixtures.

[@justintown2442]

3:16 that a little cross threaded?

[@joshmiller3673]

Pro-tip. If it's cross threaded you don't need loc tite.

[@larrys5083]

Nice that theirs lots of room under the sink, it’s not usually like that.

[@cestamp]

Of course there's lots of room, look how much they saved by not having a trap in there!

[@Zenjenn9713]

Silly question. Was that part of the counter sawed away to make it fit?

[@lorahubbel]

why didn't you put in a REQUIRED p- trap while you were under there? Its a gas leak the way it is now....

[@bcbock]

That short 90 bothers me too. And the visible control panel.

[@jacksplumbingvideos7147]

The p trap in in the basement

[@howifixit6206]

Looping the dishwasher drain hose up, fixed the sewage smell I'n my dish washer. Fixed now!

[@guitar1301]

Having a P-trap under your sink will also prevent sewer gas smell. But he obviously doesn't notice that it does not have a P-trap. I'll say it again he's a hack

[@bcbock]

@@guitar1301 The other hack thing is installing the dishwasher so that the control panel still shows. That’s supposed to be hidden under the lip of the counter top. It’s supposed to be concealed when the dishwasher is closed. That drives me crazy. I’ve seen it in a few videos on KZbin. I’m having one installed next week and now feel like I need to make sure the installer doesn’t do that to it.

[@Mockduck2020]

@@guitar1301 I noticed that too, but Richard is anything but a hack.

[@dodgeramsport01]

She wasted her money on LG crap! Hope she bought the extended warranty!

[@AStanton1966]

She should of got one with the stainless steel inner liner. They're quieter.

[@milesdavvis4498]

Awesome tutorial Buddy!! I have a question how much does it cost to install a dishwasher

[@smooveking773]

great tip on the power and smooth side wire being hot

[@dlamarsobotor4573]

Richards body of work is top shelf. We also use his term of "good" as a drinking game trigger. Great vids for sure man ! Except for the flexible power cord deal. Must be a regional thing. Rich never actually shows how to power the appliance on the plug side

[@hellospam879879]

Insert plug, I believe. (cause he talked about the polarized plug).

[@juego414]

very simple and useful explanation. ..thanks. .

[@60swag20]

Carlitos Carlitos T ?

[@johnny-z]

Why wouldn't you put a P trap on that? Is the sink, DW properly vented? Air gap?

[@73beetle19]

I don’t see a p trap under her sink. Is there a trap under the house? I’m putting in a dishwasher in my home that was built in 1971 it’s got it own p trap and drain. I think your video is great . I did learn a couple of things.

[@danbasta3677]

I love Ask This Old House! Great, informative tv show.

[@garystrahan4601]

@3:16 Clearly showing the white plastic nut being cross threaded while reconnecting it

[@MsCharae23]

Great informative video! I feel like I could do this myself now.

[@justinmata2479]

Never reuse the ferrel or nut from the pre existing compression stop, it’s bound to leak ..

[@davidm7824]

not true. I have reused them many times and never had a leak!!!! the water pressure is only 60 psi not 1600 psi.....

[@szargos]

Everything I've looked up or heard from plumbers says not to reuse them. He's got a lot of pipe there too, why not just cut it right quick.

[@Colette_Leroux]

This is so easy! I want to add a dishwasher to my mom's old house that also doesn't have a garbage disposal! Thank you so much!

[@captainpumpkinhead1512]

I can't believe I'm at the age now where I'm unironically watching This Old House clips! 😂

[@ernestovaldez2341]

🤔I'm wondering what state this installation was made in🤔😳Why was no TRAP on that drainage fixture 😳🤔😳Just thee build up smell alone "will be unbearable in 6months"😳

[@careeflewellen3737]

I'm renovating my late grandmothe😢r's home didn't know this was possible....

[@Bigfoot14000]

The lack of a P-trap, indication of a likely unvented drain, is a huge red flag. It is inexcusable that a plumber, let alone an instructional video by This Old House, would let this go by without comment and correction. Shame, shame shame!

[@10MohGG]

She needs a Garbage Deposer it’s worth it

[@modd6r]

No trap on the sink?

[@kennyg3192]

One thing I can’t believe unless she has massive back venting. I just did this a whole roughing in Ellicott city Maryland and it was all old copper DWV copper and everything was properly spaced except for one bathroom it did not have a back vent and it was properly spaced between the sink and the toilet, and it was stealing the trap water And we had it left just like that and the ladies sink because we were replacing to existing, it failed because we didn’t have a cheater vent where that 90 is should be a tea with a little scooter vent that goes above the trap level of the flood rim above the top of the drain, so the bottom of the base of sink, you normally want to go up with your cheater vent 2 inches above that line where it ties into the bottom of the sink and it will vent a lot better and if you want to put a garbage dispose on there it’s easier is the trap below the floor?

[@brownpride5125]

Why you guys use the black as a power line in white as ground enem México black always in anything is about power is ground or negative and red always is the hot o power line and white is the ground so I don't get white black is the hot so even in the electric on car red is the hot black is negative??????

[@jeanniegibbs202]

Wow you did an Amazing job that Anyone con do this!!! Great video...gonna try this with my son...I know we can do this!

[@amandamcdonald7041]

How did it go?

[@AStanton1966]

If she didn't answer you, maybe she's under water?

[@kingokafor6215]

I like how the working conditions are always ideal. The entire bottom of the cabinet is missing😏

[@derrickwydick6635]

He fast-forwarded through some of the most important aspects of installation. Good for viewing on PBS, not great for learning how to install a dishwasher.

[@Iwillnotbepushed]

Where’s the p-trap under the kitchen sink. Not to mention any kind of vent at all. Also code dictates that dishwasher and hot to sink have separate cut offs. If you are going to show these videos show everyone how to do it right. In your defense Rich I like the tape trick for the water supply.

[@bcbock]

The vent for my sink is inside the wall, but that’s also where the drain goes. In her case, I’d hope it’s in the basement, otherwise he should have installed an air admittance valve under the sink. Given that high loop is still allowed where she is, I’d think an AAV would also be allowed by their code.

[@Guillotines_For_Globalists]

They do make valves that have a 180 degree outlet and a 90 degree outlet. Would have suited this setup better.

[@bcbock]

Personally, I prefer a separate valve for the faucet and the dishwasher so shutting off the hot for one doesn’t disable the other.

[@sekritskworl-sekrit_studios]

If smooth os "Live" then what are other 2 wires? I don't want to assume green is still green... could someone please be so kind as to specify?

[@charleslong1965]

Richard...ive lost respect....there no trap and as a plumber you should have saw that, and you need a separate shut off for each fixture, not that style stop by code. You have failed me.

[@shauntampa]

Would love to see the 4 hour video of this installation.

[@jamietaylor1799]

Shouldn't take more that 2 hours at the MOST. I can do it in that time, including a new breaker/circuit from the panel.

[@bcbock]

I had my plumber install my dishwasher. It took them about a half hour. But they had already added a dedicated valve for the washer when I redid the cabinets and sink. So everything was planned out. It takes longer if you have to do a lot of modifications. For example, a dishwasher needs a dedicated GFCI outlet in my area. And we had to have a separate one for the disposal. We also had to have an air gap installed in the sink as our city doesn’t allow the high loop shown in these videos. But since it was a remodel, that wasn’t a problem. But it could take you a lot longer.

[@pawelgatorade]

once in a while p trap is not needed because sewer smells nice

[@liskaerik]

In the full episode that this clip came from they point out that there is a drum trap in the basement under the sink.

[@austinpatrick2682]

Either there's a trap in the basement/crawlspace or he has lost his freaking mind. In either case how could he not say anything about it!?

[@chrisrichard298]

In the full episode that was on TV, they mention that the trap is just below the floor, up in the cellar ceiling.

[@dillonphillips313]

*fails to mention lack of p-trap*

[@jacksplumbingvideos7147]

The trap is in the basement

[@HaloGTMaster94]

Amazing!

[@dalesworld1308]

Notice he didn't mention the lack of a trap or venting. Sometimes you just need to do what you came for and ignore the rest of the stuff that's incorrect.

[@fixmyhouse]

Facts.

[@johnsmith-sw7ii]

Hey Richard!!! Why didn;t you put a trap on that "trapless" drain????????

[@andthen5659]

this looks so easy but for my kitchen i dont have any electrical outlets under my sink so ill have to hire an electrician

[@javiery8664]

very professional video good job

[@zillaquazar]

I can't be the only one who thinks it's fucjing nuts to have the electric sockets directly under the sink ?

[@loramcclamrock5549]

Thats why they are supposed to be a dedicated GFCI outlet.

[@desthepez315]

How much would this cost to have someone come do it for you. On average?

[@max-zl1vm]

Don’t forget to test that the water is shut off by opening the faucet on hot: no water should come out.

[@jaimeos9452]

If u gonna do it right.install sink p trap

[@pololoo3320]

Is a trap required for the sink?

[@ScubaCat3]

Polo Loo nah. This old house clients enjoy that sewer gas smell in the afternoon.

[@balrajsinghpanesar8457]

Yes

[@bcbock]

Only if you follow any plumbing code, or if you don’t like sewer gas. There may be other circumstances I don’t know. The drain going straight down probably means (or maybe means) there’s a P-trap in the basement. I don’t know if that’s legal. But you don’t want two p-traps which may be why this one is missing one. I can understand not wanting to focus on that, but they should have either explained that it was wrong and fixed it or explained why it wasn’t wrong.

[@Scubamike4499]

On the full episode there is a drum trap right under the floor

[@jensschroder8214]

0:50 In Europe the ferrule is called "compression olive"

[@neosmith80]

lg dishwashers are pure crap

[@Elevendyeleven]

Did I miss the part where he connected the drain hose to the new pipe under the sink?

[@eddiepierce2475]

Code, oh you herd of code? Separate dishwasher and sink on there own stop.

[@Bremend]

More like excited not to do dishes...

[@threedog22]

It’s an LG. You’re good for at least 3-4 years. 😂

[@joshreinhofer7116]

A dishwasher must have a gcfi, but must it be a dedicated circuit?

[@iamremy-kl3xm]

Excellent teaching Sir... thank you 👏🏾👏🏾👏🏾🤙🏾

[@tmaddock71]

Where's the P trap though, surely you didn't ignore it?