Floor Joists Limitations

[RocketMan]

Hello all. Am new to this forum and not sure i am in the right area to make this post. But here goes. I am currently renovating/building a new bathroom in my house. This includes a large shower 8'x3'6" with a mud mortar bed. This bath is on the second floor and sits above the kitchen. The span is 14 feet 4 inches with floor joists of 1x10 set on 16" centers.
The inside of the 8 foot shower side sits along an inside support wall and the curb sits in the middle of the 2nd and 3rd floor joist.
One end of the shower sits on the outside support wall while the inside end sits in the interior part of the floor against an interior wall that separated the commode from the shower. There is no support wall underneath the interior dividing wall.
The subfloor is 5/8 OSB tongue and groove with 1/2" backer board on top. The shower floor is tiled.
It has a sliding glass door the weighs about 200 pounds.
The entire structure including door weighs about 1300 pounds.
Question is : is this within the limits? To me it seems to be way too heavy and i have an uneasy feeling about the whole thing being too heavy.
Any help will be greatly appreciated.

 

[TheCommish]

for 1x10 defintantaly a bad day, for 2x10 the floor must support 30 PSF on a bedroom level, 40 PSF on a liven level and the dead load and any instilled equipment. normal size tubs full of water are not usually a problem, water is 8 pound per gallon and the person in it.

species of wood makes a difference and the unit weight needs to be verified

 

[SCBO1]

After you calculate your floor weight, should probably verify if the floor joists have been cut or mutilated, may need to sister some additional material to the joist below the shower.

 

[RocketMan]

for 1x10 defintantaly a bad day, for 2x10 the floor must support 30 PSF on a bedroom level, 40 PSF on a liven level and the dead load and any instilled equipment. normal size tubs full of water are not usually a problem, water is 8 pound per gallon and the person in it.

species of wood makes a difference and the unit weight needs to be verified

Sorry, 1x10 was an error. They are 2x10. Thanks for reply. So not sure how to interpert the information. The house was built in 2006 and assuming the cheapest lumber was used, would that 1300 pounds be over the limits you quoted? If i use the 40 PSF and the shower is 28 sq feet that would be 1120 pounds which is under the 1300 pounds dead load i came up with? I guess that means that any live load would also push it beyond the limit? Is this thing dangerous?

 

[RocketMan]

After you calculate your floor weight, should probably verify if the floor joists have been cut or mutilated, may need to sister some additional material to the joist below the shower.

Wow. I do know the floor joists have been cut for the drain on the inner wall area and no way to scab in another support beam. Looks like i am going to have to tear it all out and bring in a fiberglass pan.

 

[bill1952]

You can have notches and holes in joists, they just have to be limited to what code allows. I'd say 2x8 for you span is fine, with permitted notches and holes.

 

[Plumb-bob]

You will not find it in codes, but a floor span will be more affected by loading at mid span and less affected by loading closer to supports.

Floors support very heavy things as a matter of course: tubs full of water, pianos, family dance parties. Floor joist spans are designed to deflection limits, not failure limits. So unless your floor joists are badly butchered you should be ok. And if they are butchered you should be able to reinforce them.

Best ask your local inspector!

 

[SCBO1]

Rocketman, Please don't go to extreams on my account, it's only an observation from afar!

 

[RocketMan]

You can have notches and holes in joists, they just have to be limited to what code allows. I'd say 2x8 for you span is fine, with permitted notches and holes.

You know i think you are right. The notches i saw were real close to the inner support wall (About 6 inches) where they ran the plumbing through. The notches were at least 6 feet from the inner wall of the shower. They just notched them from the top, not the bottom. Had it been the bottom i would have immediately been alarmed. I should Hhave taken some pics while the floor was out.
My biggest concern is the floor would give way when someone is taking shower. I don't know if a floor just all of a sunnden caves in or not. Nevr heard of one doing that. My guess is that the floor would start swaying/bending downwards before collapsing. So far there is no visable deflection in the kitchen ceiling.

 

[RocketMan]

Rocketman, Please don't go to extreams on my account, it's only an observation from afar!

No problem. I am really looking for ideas and alternatives if i need one. All input is appreciated and considered. Trying get away from tearing out all that work. But, i will do it if it needs to be done.

 

[RocketMan]

You will not find it in codes, but a floor span will be more affected by loading at mid span and less affected by loading closer to supports.

Floors support very heavy things as a matter of course: tubs full of water, pianos, family dance parties. Floor joist spans are designed to deflection limits, not failure limits. So unless your floor joists are badly butchered you should be ok. And if they are butchered you should be able to reinforce them.

Best ask your local inspector!

Bob, that really makes sense. Just common sense and reasoning tells me that what you say is true. The shower is strongly bordered on two sides, one is 8 feet along the inner support wall and the other is bordered 3.5 feet along the outside support wall. Something tells me that those two areas are the strongest and capable of handling a lot more weight than the middles or near middle spans.
I guess my question would be, just how much of that 1300 [pounds is actually transferredborne by the support walls versis the floor joists 2 and 3 from the inner support wall? How would one even find out? LOL

 

[RocketMan]

After you calculate your floor weight, should probably verify if the floor joists have been cut or mutilated, may need to sister some additional material to the joist below the shower.

Yes, if i had access to the joists i could install some "cross" braces between the joists. According to what i have read the braces would transfer the deflection to the point where the joists rests on the sill plate? But i would have to tear out the kitchen ceiling to do that. Not sure which one is worse, ceiling tearout or re-do the shower pan with fiberglass.

 

[bill1952]

Extremely unlikely anyone would end up wet and naked on first floor.

This might help:

https://buildingadvisor.com/wp-content/uploads/2012/05/Notching__Boring_Guide.pdf

 

[Joe.B]

 

[RocketMan]

Extremely unlikely anyone would end up wet and naked on first floor.

This might help:

https://buildingadvisor.com/wp-content/uploads/2012/05/Notching__Boring_Guide.pdf

Excellent information. Thanks. When this house in 2006 in El Paso County there was no inspections required. Only restrictions were the ones in the Deed Restrictions Covenants. So most of the houses here were built to standards, but some were not. As a result some shortcuts were made. The notches i mentioned are not within the code guidelines. So i am still looking into the cost of a lightweight custom built shower pan. It would be much cheaper to do a tearout and replace NOW before the tiles are installed rather than later. Now i would lose about 300 dollars in materials whereas later it would be in the thousands.

 

[Joe.B]

 

[Mark K]

If the shower has been in use since 2006 and you are not seeing distress I would calm down and take a deep breath before taking any action.

If you are concerned that the existing framing is not adequate it may be useful to have an engineer look at the framing. The engineer will consider provisions in the IBC which may indicate you do not have a problem. If changes are warranted the engineer can help to identify less intrusive options.

The other option appears to be to tear out the existing and install new framing. I suggest that it will be cheaper and less disruptive to hire an engineer.

 

[RocketMan]

If the shower has been in use since 2006 and you are not seeing distress I would calm down and take a deep breath before taking any action.

If you are concerned that the existing framing is not adequate it may be useful to have an engineer look at the framing. The engineer will consider provisions in the IBC which may indicate you do not have a problem. If changes are warranted the engineer can help to identify less intrusive options.

The other option appears to be to tear out the existing and install new framing. I suggest that it will be cheaper and less disruptive to hire an engineer.

Thanks for that info. No, this is a new shower that has never been used. It was started in 2006 and i have installed the pan but after installation and weight calculation, i got a very uneasy feeling. The shower at this point weighs a little over 1300 pounds and that is between 50 and 60 PSF. That exceeds the allotted 40 PSF that is allowed by code IF you use the strongest 2x10's. I do not even know what grade the lumber in this house is. So maybe it is safer to scrap what is there and start over.
Am looking into that Engineer thing as well. Having trouble finding one in this West Texas city.

 

[bill1952]

Many architects are qualified to do this. It might be easier to find an architect.

It is probably not that much work to repair - reinforce - one joist because of one illegal notch or hole. I'm guessing on your comments that it would mean removing some sub flooring or ceiling to gain access.

Would be much easier to help if you had a photo.

 

[tbz]

As to the method of the shower pan I would tend to lean more towards a Schulter system rather than mud pan or fiberglass.

Way better on the weight besides being just a better shower base system.

 

[RocketMan]

Many architects are qualified to do this. It might be easier to find an architect.

It is probably not that much work to repair - reinforce - one joist because of one illegal notch or hole. I'm guessing on your comments that it would mean removing some sub flooring or ceiling to gain access.

Would be much easier to help if you had a photo.

Yes. The part that would need the sister support is already tiled and tub on top of it. Can not even take the ceiling out and get to it because that part is right on top of the kitchen cabinets. They would have to come out before removing the furdown as well. LOL what a fix. I don't have pics of the joists. I have also found out that the length of the joists are actually 12 ft 8 inches, not the 14 ft 4 inches as i stated before. Not sure it would make any difference.

 

[RocketMan]

As to the method of the shower pan I would tend to lean more towards a Schulter system rather than mud pan or fiberglass.

Way better on the weight besides being just a better shower base system.

I will look into that system. It doesn't require mud?

As to the method of the shower pan I would tend to lean more towards a Schulter system rather than mud pan or fiberglass.

Way better on the weight besides being just a better shower base system.

Ok, i looked into this and it appears they don't make one that is longer than 72" . My pan is 36" wide by 92" long. I was really ready to get one of these because it would save me lots of money and time. Thanks for the tip

 

[tbz]

I will look into that system. It doesn't require mud?

Ok, i looked into this and it appears they don't make one that is longer than 72" . My pan is 36" wide by 92" long. I was really ready to get one of these because it would save me lots of money and time. Thanks for the tip

Just put 2 together and tap the seam, I needed to move the drain more than a few times to avoid a floor joist below, you can slice and add no problem.