Exact Toilet Rough In Sizes

Installing a new throne or replacing an existing one requires precise rough in measurements. These figures determine toilet selection, proper fit, and smooth installation. But measuring this key dimension often gets overlooked or done incorrectly.

This leads to buying the wrong toilet, gaps between tank and wall, lack of legroom, and other problems. Accurately gauging rough in size ensures everything fits perfectly in the bathroom.

Defining Toilet Rough In Dimensions

The rough in measurement refers to the horizontal distance between the toilet's drain pipe and the finished wall behind it. Plumbers determine this key plumbing figure when installing drain and vent piping during a bathroom's rough stage.

Standard modern rough in size is 12 inches. But dimensions can vary from 10 to 14 inches in older homes depending on original drain locations. This crucial measurement affects toilet model selection, proper fit and operation.

Consequences of Improper Rough Ins

Installing a toilet without verifying rough in size has several risks:

• Toilet loose, unsteady, or unable to mount flush on floor
• Large gaps visible between tank and wall
• Inability to fully open tank cover
• Bathroom or closet doors blocked from opening
• Wasted money buying the wrong toilet

Getting accurate dimensions mitigates these problems. But even with precise figures, installed toilets may not fit right or have issues. Using spacers, seals, and offset flanges facilitates adjusting rough openings. We detail options later.

Common Toilet Rough In Sizes

As mentioned, 12 inches is the standard modern dimension. But other numbers occur in older construction or specialized models:

• 10 inch - Fits smaller, compact bathrooms
• 12 inch - Most popular size with widest product options
• 14 inch - Needed for comfort/elderly height toilets
• 16-18 inch - Required for wall mount, corner units

The 10 inch rough in works for tiny powder rooms with storage limitations. Meanwhile, the larger 14 inch size provides extra leg room with taller bowls. For customized corner installations, bigger dimensions from 16-18 inches facilitate specialized carriers.

Factors Influencing Toilet Rough Ins

Many interrelated variables affect rough in figures. Understanding them helps select suitable products during toilet replacements or new baths:

• Age and era of home construction
• Original drain pipe routing from rough plumbing
• Standard, compact or comfort height bowl
• Available bathroom space and dimensions
• Elderly, disabled, or accessibility needs
• Desired toilet shape and design - round versus elongated

Older properties often deviate from the 12 inch norm due to past construction trends. Meanwhile, user physical traits and accessibility impact toilet shape options. Corner units also need bigger spaces. Identifying these interactions facilitates ideal rough in sizes.

Techniques for Measuring Rough Ins

Now let's explore methods for gauging accurate rough in figures using basic tools:

Measuring Existing Spaces Without Toilet

For unfinished bathrooms getting new fixtures, simply measure from backing wall material to the toilet stub out:

1. Locate circular stub out pipe in floor
2. Visually determine midpoint of flange pipe
3. Measure straight from wall face to pipe midpoint

Remember to account for any finish floor layers that get added later when taking the measurement. Drywall, tile and other coverings change totals. Not planning for them leads to problems down the line.

Gauging Rough Ins With Installed Toilet

In spaces with existing thrones, start by locating the closet bolts securing the bowl to the flange. From there:

1. Find bolt caps on toilet base
2. Visually determine centerpoint between them
3. Measure straight from wall to approximate bowl midpoint

You'll likely need to detach the retaining nuts and temporarily lift the unit via an adjustable wrench to view the full tailpiece for accurate numbers.

Measuring Offset Rough Ins

Diagonal corner toilet spaces add complexity. This technique works:

1. Mark the approximate midline of desired toilet location
2. Measure from the midline to back corner wall 1
3. Measure from the midline to back corner wall 2

Compare the two perpendicular figures to corner carrier product specs for proper selection. Off-angle installation positions help maximize small bathroom real estate.

Confirming Rough Opening Size

It's prudent to double check your rough in figures, especially in older homes. Simply use a level to transfer your initial measurement over to the adjacent wall and measure across for verification:

1. Make initial wall-to-flange measurement
2. Butt Level against that wall spot
3. Transfer measurement laterally to side wall
4. Measure opening again and compare

Identical measurements confirm accuracy and peace of mind. This simple confirmation prevents unpleasant surprises after buying fixtures and avoids wasted financial, time and emotional resources from product returns, replacements or shims, spacers & large gaps.

Adjusting Non-Standard Rough Openings

What if your rough in measurement differs from typical 12 inch size toilets? Adjusting existing plumbing facilitates proper modern bowl installation. Here are two approaches:

Offset Toilet Flanges

Offset flanges install atop the existing stub out pipe to shift its center:

• Fine tune rough in 1/4, 1/2 or 1 inch
• Rotate integral closet bolt holes
• Adapt 10, 12 and 14 inch spaces

These adapters add an inset collar that extensions the drain pipe location forward or back from the wall in small increments. Offset capability ranges from 1/4 inch to 1 inch depending on product selection. This facilitates zeroing in on required rough in figures without plumbing changes.

Replacing Drain Pipe Section

Sometimes the existing toilet flange location needs more significant adjustment. This involves replacing a portion of the drain line:

1. Cut out old drain pipe section
2. Install new pipe at appropriate depth
3. Attach new flange at precise rough in distance

Although more intensive, this completely remedies difficult rough openings beyond just an inch or so. It positions the new tailpiece section at any desired depth relative to the finished wall. The downside is opening up the wall and floor compared to simply adding an offset flange.

While seemingly simple, accurately measuring toilet rough in dimensions has big implications on product selection and headache-free installation. Taking the extra time to precisely gauge this key figure ensures you get the right bowl for your bathroom needs and constraints.

Likewise, knowing ways to adapt existing plumbing quirks prevents scrapping old drain lines. The reliable techniques and adjustment methods covered equip you to install modern, comfortable thrones into almost any home. Just be sure to confirm your figures before purchase!