Rough-In Dimensions For Each RV Toilet

Updated 08/10/2025 | Published 09/14/2023

Products Featured in This Question

Lippert Flow Max RV Toilet - Standard Height - Elongated Bowl/Seat - Slow Close Lid - White Ceramic

(17)

$298.04

Dometic 301 RV Toilet - Low Profile - Round Bowl - White Polypropylene

(33)

$210.25

Dometic 320 RV Toilet - Standard Height - Elongated Bowl and Seat - Tan Ceramic

(557)

$408.06

Dometic 510 RV Toilet - Standard Height - Elongated Seat - White Ceramic

(135)

$742.48

Dometic 300 RV Toilet - Standard Height - Round Bowl - Tan Polypropylene

(60)

$211.99

Question:

Do you guys have a list of the rough ins for your toilets? The height measurements are great but it'd be nice to know if the toilet is actually going to fit.

asked by: Willie

Expert Reply:

Yes, I've made a little list below of the different rough-in measurements for each toilet part number:

# DOM74FR - 8.5"
# DOM64FR - 8.5"
# DOM24FR - 8.75"
# DOM57FR - 10"
# DOM37FR - 10"
# DOM77FR - 10"
# DOM67FR - 10"
# DOM87FR - 11"
# DOM27FR - 11"
# DOM99FR - 11"
# DOM29FR - 11"
# LC67AF - 12"

If you need any other measurements or have any other questions just let me know.

expert reply by: Kevin C

Rob

7/11/2025

I have small bathroom attempting to pick right size RV toliet The toliet room size is depth 30" x Width31" x height 82.5". What would you suggest to be the best size toliet to fit this area. The toliet will have water available and waste will be piped to small septic tank.

Robin H.

7/12/2025

@Rob do you have the rough-in measurement as well? Or is this something new you're adding in so it can be whatever you need it to be? What I would do is take the measurements from the toilet and mock it up to see what you think will work best. Length is probably the only real concern here, and I do recommend getting an elongated bowl if possible. If you have an 11" rough-in measurement, and you think 20-1/4" long will work, the Dometic 510 Full-Timer # DOM29FR would be the best option. Keep in mind, you also need to think about how much room you might need for anyone sitting on it in the bathroom since your own height and size can also play a role in this.

Rob R.

7/14/2025

Robin - the measurement of the bathroom enclosure is 30" L X 31" W x 82.5 "H. Are you still of the opinion to use the domestic full timer # DOM29FR for this installation? We do have water supply and ability to depose waste to small septic field.

Robin H.

7/15/2025

@RobR I got the measurements, thanks. I would still do what I said and mock it up to see what you think in there for a better idea for you personally. You also still need that rough-in measurement, which is the distance from the wall to the center of the flange to know what will fit.

See All (6) Replies to Rob ∨

Mark G.

8/10/2025

To follow up, and in addition, I have a 2016 Jayco Octane SL 273. It has a corner mounted toilet. Rough in to wall is 8.5 on one side 9 on the other, but this is not counting the space behind from that direct back. Is there any chance of getting measurements that will tell me the angles? I like to use the porcelain 310. But not sure it would fit. They don’t make this easy.