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Support For Bathtub

ICE said:
How about fat Yolanda and her king size water bed? We're talking some pounds now. I had a case where there was a shower pan built that lasted about six months and leaked. This was a redevelopment project. There was a meeting at city hall where I met the owner for the first time, all 600 pounds of him. When a new contractor came to the counter to get a permit I told him that his best bet would be to put a foundation under the shower pan or it will fail again. I was summoned to the city managers office and asked: "Are you calling the citizens fat?" I said, "Well yes, yes I am."
One of the engineers I work with used to be a plan checker and told me about a phone call he got one time from a concerned tenant regarding a water bed on a second floor. My friend explained that waterbeds are obviously quite heavy and that a certain amount of deflection could be expected, depending on a number of factors. Before he could start explaining what these factors were he was interrupted by the tenant saying, 'Okay, I see it', referring to the sagging floor! He managed to get the garden hose connected and the bed drained before the floor collapsed.

 
Rio said:
One of the engineers I work with used to be a plan checker and told me about a phone call he got one time from a concerned tenant regarding a water bed on a second floor. My friend explained that waterbeds are obviously quite heavy and that a certain amount of deflection could be expected, depending on a number of factors. Before he could start explaining what these factors were he was interrupted by the tenant saying, 'Okay, I see it', referring to the sagging floor! He managed to get the garden hose connected and the bed drained before the floor collapsed.
See when that place was framed a six hundred pound inspector would have found out the floor joist were inadequate during the rough in.
 
either that or every building department should hire a 600 pound gorilla! besides, they'll work for bananas. And they would be great in a best ball golf tournament! after some of the exchanges lately on the forum it's nice to see some humor.
 
My point is not to argue for or against the additional joist under a bathtub. I have been directly involved in the design, construction and inspection of over 3,000 residential units in the last few years and none of them had an additional joist under any of the upstairs bathtubs and, so far, we have not had any warranty issues. However, I would never make the argument that because "I have been doing this for X amount of years or have built X amount of units without incident" we do not need to consider what is recommended by the American Wood Council in the Wood Frame Construction Manual which is in fact referenced in the International Building Code. In the event a floor system failed due to loads in and around a bathtub the statement, "I have been doing this for X amount of years or have built X amount of units" doesn't mean anything. Instead, the designer and builder need to be prepared to argue that the building was designed and built at or above the minimum. And, finally, how many people in this forum weigh just 150 lbs? My guess is that the average weight will be closer to 200 lbs and all the literature suggests we are getting bigger, not smaller.
 
Yeah, a couple of times. OK, that might be a bit of an exageration but...............
 
I think someone alluded to this before but I would be more concerned---and I am not at all concerned---about the actual floor sheathing/decking supporting the weight of the tub and its contents, especially if the tub is cast iron. The last cast iron tub I looked at had several supports located on the bottom of the tub floor which would appear to have the potential to dent or puncture the 5/8" - 3/4" osb or plywood floor. I wonder if it is possible that companies such as Koehler, Eljer and American Standard have any smart engineers who account for the weight of their product and its future contents on standard code compliant products and floor assemblies?
 
You are not compelled to design based on your perception of the weights of the occupants. The code only requires the building be designed to support the loads listed in the code. If this were not the case one might suggest that all residential projects be designed for 100 psf since you could have a party where everybody is sholder to sholder.
 
GBrackins said:
either that or every building department should hire a 600 pound gorilla! besides, they'll work for bananas. And they would be great in a best ball golf tournament! after some of the exchanges lately on the forum it's nice to see some humor.
Can you teach Gorillas how to play darts? I would prefer orangutans...then they can write "any which way but loose" for their guard rail comments.

Have you visited the Palaearctic–African Bird Migration Forum, a Discussion of the Palaearctic-African Songbird Migration traffic across the Sahara...and other things? It could probably use a few more posts every week in my opinion.
 
Oh ICE Magnificent one you are correct...

May your lips never freeze to your margharettia.

The correct answer from the sealed mayonaise jar on Funk and Wagnells front porch is.

Multiple design loading conditions based on time;

7 day loading, 30 day loading, and long term 100% loading................

7day and 30 day would calculate ot at somewhat reduced load factors...

those would be for live loads like fill / empty tubs and snow in moderated climates -

the calculation adjusts the Fb bending stress in parallel grain wood fiber b increasin that number to 115% 115%

and in some wind cals to 133% and as this is in the denominator of the fractional calc it is an increas in capacity.

The water bed would be a load that could and should not be reduced - same for filled spa pool type tubs - not drained

the water mattress 6 to 9 inc weighs 32 to 45 pounds per foot all the time well above the code 30 lbs LL/SF (15 sheets of 1/2 in gyp??)

so the typ res loads do not account for them. Sales people of such devices say the place the same load as a refrigerator. to which I reply Good try filling your bedroom with refrigerators.

Other items that designers (RDP or not) should consider are Kitchen Islands on large size tile floor with stone countertops.

The code lets them build and us approve the "Worst Possible"

Carnac divines the answer:

Siss Boom Baah!!!

Question??

What souds does an exploding sheep make????
 
There are also table sections that provide 20 PSF DL and those are more conservative and applicable to the island and some larger tubs.

as the reviewer IF proper plans address built in or increase load areas then we have something to review and advise..

otherwise we with experience can stand back and say here is where the stress (permanent deformations) vracks will appear.
 
ICE said:
A couple bags of sackcrete under the tub was popular in a lot of places I've worked. They left it in the bag and the ambient moisture would be enough to get it to set up.
A plumber I knew would put down a sheet of plastic and dump a bucket of drywall joint compound on it to bed a tub.
 
jim baird said:
A plumber I knew would put down a sheet of plastic and dump a bucket of drywall joint compound on it to bed a tub.
Mortar and joint compound crumble too easily. Sackcrete has rocks that will poke a hole. Tapioca pudding costs too much (well the good stuff with the large pearls).
 
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ICE on the tub support idea I recently watched a "This old house" segment where after install the plumber half filled the tub and the applied expansing closed cell foam beneath, let set and drained.

Actually not a bad idea as the water weight prohibited the foam from lifting the tub base and created a solid foam base.
 
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Architect1281 said:
Question??

What souds does an exploding sheep make????
My son plays my old warcraft dos games...exploding sheep make a baaaahhh-ploop sound. I could send you a wav file if you like.
 
send it .... send it .... everyone needs an exploding sheep sound on their computer. I use Dorothy from the Wizard of Oz for my error sound, "What would you do if you had a brain?" Might make for an interesting sound for emptying the trash.
 
Victoria,
Reading something on the internet may not be accurate with what is required by the building codes. Note the name of this forum: The Building Code Forum. We can appreciate your desire to play in this "sandbox" but you have "hijacked" a posting that is nearly 5 years since the last posting. I suggest that you try to keep your comments focused on relevant topics (recent postings) where it seems that your input will provide useful information from either personal experience or further reflection on what the Codes (the UBC, IBC, IRC and state codes) require.
Please don't go away. Stick around and you will learn many things just by standing around!
 
Good question, currently dealing with this. Using a "free standing" tub. So there is no decking/framing to support the tub which sits inside. 2 story home. Was told that code required that an elevated 2x4 structure with decking needs to be created to support the tub. Decking then will be tile flooring.

Is this really necessary? Free standing tubs often don't look that great sitting up on a pedestal/raised 4" decking and not sitting level on the same tile flooring.

Thoughts?
 
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@ ! @

Seth,

Please provide the applicable Code & Edition that your
are referencing.......Also, does your "free-standing tub"
have support legs ?.......Some do and some do not !


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serveimage





@ ! @
 
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