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Roll-in shower in a house allowed?

Mr. Inspector

SAWHORSE
Joined
Nov 28, 2009
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Location
Poconos/eastern PA
2009 IRC P2709.1 Construction.
Shower receptors shall have a finished curb threshold not less than 1 inch (25 mm) below the sides and back of the receptor. The curb shall be not less than 2 inches (51 mm) and not more than 9 inches (229 mm) deep when measured from the top of the curb to the top of the drain. The finished floor shall slope uniformly toward the drain not less than 1/4 unit vertical in 12 units horizontal (2-percent slope) nor more than 1/2 inch (13 mm), and floor drains shall be flanged to provide a water-tight joint in the floor.

Because of the required curb does this mean I can't have a roll-in shower in my home?
 
I've been doing it for 27 years in every home I've built and no inspector has said anything, we make the entire room the shower receptor and do the 48 hour water test by turning up the membrane at the door into the room, so the inspectors who sign off the water test see what we are doing. BTW, we just do it for appearance but I've had several customers mention that it's a good idea to be prepared when they get older.

BTW, it's my understanding that the curb requirement was coming our of the code but that might just be California.
 
I've been struggling with this too. We had an inspector (I'm in CA) require wall hung toilets as the "floor as the receptor" solution had its weak link at the toilet/floor transition. The linear shower drains are everywhere now and I keep thinking of how quick the room would flood if the main line gets clogged, and it's the shower (or tub) that will overflow long before a sink. Then the doorway...how does the membrane resolve itself there?

In the old days, we used to design the walk in showers as being deep enough (8') to get the required 2" difference in drain to curb dimension (1/4"/ft floor slope). I'm interested in how many linear drains are getting approved with the requirement of full membrane floors, turned up at the walls, and doorways and toilets being a weak link?
 
I've been struggling with this too. We had an inspector (I'm in CA) require wall hung toilets as the "floor as the receptor" solution had its weak link at the toilet/floor transition. The linear shower drains are everywhere now and I keep thinking of how quick the room would flood if the main line gets clogged, and it's the shower (or tub) that will overflow long before a sink. Then the doorway...how does the membrane resolve itself there?

In the old days, we used to design the walk in showers as being deep enough (8') to get the required 2" difference in drain to curb dimension (1/4"/ft floor slope). I'm interested in how many linear drains are getting approved with the requirement of full membrane floors, turned up at the walls, and doorways and toilets being a weak link?
Robert:

I agree that wall hung should be required, I've had that problem over the years and have it again right now, the problem, as I have diagnosed it, is the linear drain manufacturers have gone to convoluted weep passages that eventually get partially plugged and water backs up to the toilet flange, as much as I've tried to seal the flange they eventually leak, in my case I use drainage matts over the membrane to make the water flow quickly but they cut two ways, the matts can cause the water to flow quickly in the upward direction as well if there is any blockage slowing water in the weeps. In the past when I've had this problem I've installed an additional buried (under the stone or tile) shower drain at the high end or near the toilet flange, I'm going to be doing that again.
 
2009 IRC P2709.1 Construction.
Shower receptors shall have a finished curb threshold not less than 1 inch (25 mm) below the sides and back of the receptor. The curb shall be not less than 2 inches (51 mm) and not more than 9 inches (229 mm) deep when measured from the top of the curb to the top of the drain. The finished floor shall slope uniformly toward the drain not less than 1/4 unit vertical in 12 units horizontal (2-percent slope) nor more than 1/2 inch (13 mm), and floor drains shall be flanged to provide a water-tight joint in the floor.

Because of the required curb does this mean I can't have a roll-in shower in my home?

Can do it in accordance with the following IRC administrative section as applicable with the AHJ.

R104.11 Alternative materials, design and methods of construction and equipment.
The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, not less than the equivalent of that prescribed in this code. Compliance with the specific performance-based provisions of the International Codes shall be an alternative to the specific requirements of this code. Where the alternative material, design or method of construction is not approved, the building official shall respond in writing, stating the reasons why the alternative was not approved.
 
I have encountered a few. Only one was the entire room. The others were large and the receptor extended 4' to 5' beyond the front. The slope was such that the farthest point of the receptor was at least 2" above the drain. What happens when a stall with a 2" threshold is plugged? In short order the water flows over the dam. Running under a toilet is not the issue....having a drip pan under a wheelchair is.

Some people just want the shower with no dam...it works the same way.
 
Last edited:
ICE said:
Some people just want the shower with no dam...it works the same way.

Every architect I know is designing showers with linear drains and no curb now, also women who read the magazines see pretty pictures of linear drain showers and demand them.
 
What is the consensus? If doing linear drains with no curb....membrane the whole floor turning up at the walls and do wall hung toilets?
 
One problem is that PA Uniform Construction Code did not adopt the first chapters of the code and did not add anything like R104.11 in it.

The 2009 IPC doesn't require curbs like the 2009 IRC. The IPC also specifies prefabricated receptors are allowed but the IRC seams to always require a lining:

IRC P2709.2 Lining required.
The adjoining walls and floor framing enclosing on-site built-up shower receptors shall be lined with one of the following materials:
1. Sheet lead,
2. Sheet copper,
3. Plastic liner material that complies with ASTM D 4068 or ASTM D 4551,
4. Hot mopping in accordance with Section P2709.2.3 or
5. Sheet-applied load-bearing, bonded waterproof membranes that comply with ANSI A118.10.
The lining material shall extend not less than 3 inches (76 mm) beyond or around the rough jambs and not less than 3 inches (76 mm) above finished thresholds. Sheet-applied load bearing, bonded waterproof membranes shall be applied in accordance with the manufacturer's installation instructions.

Does this mean in a house you cannot install a molded shower floor unless you install a liner also?

I was also wondering how you do a shower pan inspection in a commercial building. Like a large tiled locker room with many tiled floor showers with no curbs that are built on slabs.
 
If by molded shower floor you are talking about a one piece plastic/fiberglass floor with plastic/fiberglass walls, that is not an "on site built up shower". It is like a fiberglass bathtub.
 
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Right or wrong, I have allowed it....Like ICE said....If it backs up, it backs up. Why is it going to stop at 3"? Unless you are bypassing a required overflow drain, it is stupid code. Why is there no minimum on sink depths?
 
2012 IRC

P2709.1 Construction. Where a shower receptor has a finished curb threshold, it shall be not less than 1 inch below the sides and back of the receptor. The curb shall be not less than 2 inches and not more than 9 inches deep when measured from the top of the curb to the top of the drain. The finished floor shall slope uniformly toward the drain not less than 1/4 unit vertical in 12 units horizontal

(2-percent slope) nor more than 1/2 unit vertical per 12 units horizontal (4-percent slope) and floor drains shall be flanged to provide a water-tight joint in the floor.

Code commentary:
“This section regulates three aspects of shower receptors: (1) threshold height, (2) finished floor slope and (3) connection of the floor drain to the receptor. For factor-fabricated shower receptors, the requirements of the section are automatically covered by the applicable standard, ANSI Z124.2 and CSA B45.5. This section provides the necessary information for field-fabricated shower receptors.

The first part of the first sentence of this section allows for a shower receptor to not have a curb. This is necessary to enable “zero height threshold” shower receptors to be installed for wheelchair access or for ease of access for disable users. If the shower receptor is to be designed with a threshold, this section requires that the top of the threshold be not less than 1 inch below the sides and back of the receptor. This is required so that if the drain should clog, water will overflow the threshold before overflowing the back or sides of the receptor. With respect to the top of the drain, the top of the curb cannot be less than 2 inches above the drain. This allows for some amount of water storage in the receptor so that if the drain is sluggish or a washcloth is accidently dropped over the drain, the user will notice the accumulation of water on the floor before water begins flowing over the threshold. There is also a maximum height of the top of the threshold above the drain of 9 inches so that the user does not have to step too far down into the receptor.

The pictures below are types of collapsible threshold approximate 1 ⅜ - inch height.



Flexible Threshold.JPG Collaspable.JPG
 
Showers on slabs, no pan or room test. No place for the shower to leak below.

We've had a roll in shower on a 2nd floor, entire bathroom floor was tested with 2" water. Lots of back and forth and a temporary curb at doorway. Schluter, I think it was, makes products for this type of application to seal toilet flanges. The architect on this job went nutzzzzz, she had a strong dislike for me during this period of specs and testing.
 
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Well it's good they let you not have a curb in the newer code but I have to go by the 2009 which requires it. It says shall.

Rick:

Inspectors have been looking the other way on this for 27 years that I know of because it makes sense, and that was long before the latest codes didn't eliminate it. It's not our fault that your jurisdiction hasn't adopted the latest code, it's you fault and certainly fertile grounds for a lawsuit against the AHJ that hasn't adopted it. Pick up any glossy magazine showing plumbing products and I doubt that you will even see a curb anymore.
 
As mentioned it is justified using the IPC; could a code modification using the 2012 IRC permissible?

RP5–09/10

P2709.1

Proponent: Eric Gundersen, Masco Bath representing Masco Bath

Revise as follows:

P2709.1 Construction. Where [delete: S] shower receptors have a finished curb threshold it shall [delete: have a finished curb threshold] be not less than 1 inch below the sides and back of the receptor. The curb shall be not less than 2 inches and not more than 9 inches deep when measured from the top of the curb to the top of the drain. The finished floor shall slope uniformly toward the drain not less than ¼ unit vertical in 12 units horizontal (2-percent slope) nor more than ½ unit vertical per 12 units horizontal (4-percent slope) [delete: inch per foot,] and floor drains shall be flanged to provide a water-tight joint in the floor.

Reason: Not all shower receptors have a finished curb threshold. Those used in accessible buildings are not required to have one, and with an ageing population, the need to eliminate thresholds over which people need to step is important. As long as the shower receptor has adequate provisions to drain the water into the waste system, there should be no need for such a threshold. The IPC does not include such a requirement. To rectify an editorial error in the slope statement.

http://www.iccsafe.org/wp-content/uploads/IRC-PM1.pdf
 
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Compliance with the IPC should be at least equivalent to compliance with the IRC plumbing provisions.
Check enabling legislation and PA adopted modifications (including Chapter 1).
 
Roll in showers are not addressed in the IRC so you are directed to the IPC. Find a prefabricated shower that meets 417.1 and you are code compliant.

P2601.1 Scope.
The provisions of this chapter shall govern the installation of plumbing not specifically covered in other chapters applicable to plumbing systems. The installation of plumbing, appliances, equipment and systems not addressed by this code shall comply with the applicable provisions of the International Plumbing Code .

417.1 Approval.
Prefabricated showers and shower compartments shall conform to ANSI Z124.2, ASME A112.19.9M or CSA B45.5.
 
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