floor weight per square foot

jda

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Aquarium is not a live load.

I have done 180g reef and cichlid tanks on main floor with 2x10 joists running perpendicular to the tank. No issues. Also had 12-15 people in the same room during graduation and other parties... at 150-200 lbs per adult. The stand did span at least 4 joists and there was foundation under the wall. I might go up to a 300g tank and have seen plenty a 300dd on the main flooor, but no more for me.
 

Kmst80

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My floor should have collapsed ages ago then. I got a 200 gallon on 125x50 mm hardwood floor joists that span 3 meters from hardwood bearer to bearer. Tank is sitting a little of centre between the bearers and sits on 6 joists. I doubled up on the joists coz I calculated a load of 1.5 tonnes of tank,stand,water,rock etc.
She's been up and running 9 month and laser tells me still level.
 

jda

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I just looked in my book and it says 30-90 PSI for a floor with 16 inch center 2x10 or larger floor joists and 23/32 T&G OSB or ply.

I googled the live load from 2015 RBC and this is a minimum for the whole room, not a single area, so a 10x10 room needs to be able to hold 4000 pounds at a minimum. That is all that they are referring to.

If 40 PSF for each foot was real, then a woman would have to weigh like half of a pound to walk on a floor with a high heel on with 1/16 square inch area.

Posts won't hurt anything if it makes you feel better.
 
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BubblesandSqueak

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My floor should have collapsed ages ago then. I got a 200 gallon on 125x50 mm hardwood floor joists that span 3 meters from hardwood bearer to bearer. Tank is sitting a little of centre between the bearers and sits on 6 joists. I doubled up on the joists coz I calculated a load of 1.5 tonnes of tank,stand,water,rock etc.
She's been up and running 9 month and laser tells me still level.
did you happen to see the pic I posted of where I'm placing the tank? it will sit on 5 2x12s. I came across an article that someone appears to have asked a similar Q years ago. but it's what I was expecting. 220 pounds per square foot. mine would be on 2x12's.
(sorry, not sure if I can post the below link)
 

Spicy Reef

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Aquarium is not a live load.

I have done 180g reef and cichlid tanks on main floor with 2x10 joists running perpendicular to the tank. No issues. Also had 12-15 people in the same room during graduation and other parties... at 150-200 lbs per adult. The stand did span at least 4 joists and there was foundation under the wall. I might go up to a 300g tank and have seen plenty a 300dd on the main flooor, but no more for me.
was the room 125 sq ft, then u were safe :)
200 lbs x 15 = 3k + tank 2k = 5k lbs divided by 40lbs = 125

All this being said, I remodel for a living and it takes some serious "live load" pounding to dismantle a house... however ,my 150g tank sagged my up-2-code floor by 3mm so I added a post :)


edit...
this was 2x12 joists over 10'
 

jda

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I have built houses and commecial buildings in a past life - not for many years. I do work in real estate now and I have read IBC and RBC and have given expert testimony on them (not fun). People mess them up all of the time. They are just minimums. There is no issue with erroring on the side of caution, but I would put a 300dd in that are without thinking twice about it.
 
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BubblesandSqueak

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I just looked in my book and it says 30-90 PSI for a floor with 16 inch center 2x10 or larger floor joists and 23/32 T&G OSB or ply.

I googled the live load from 2015 RBC and this is a minimum for the whole room, not a single area, so a 10x10 room needs to be able to hold 4000 pounds at a minimum. That is all that they are referring to.

If 40 PSF for each foot was real, then a woman would have to weigh like half of a pound to walk on a floor with a high heel on with 1/16 square inch area.

Posts won't hurt anything if it makes you feel better.
sorry, I'm not trying to be a PITA. 30PSI for a 2x10 floor would be 12x12=144x30=4290PSF? just trying to figure out what the floor is rated for. standard 2x12 joists, 16" centers, span of? (mine is 72" over a 2x6 frame.). the water alone over a 36" square is 1300pounds. (8.6pounds per gallon)
 

jda

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We are mixing terms.

That is not live load as calculated by RBC. It is the whole area for the entire room, at a minimum, would be 4290 pounds total for that 12x12 room at 30 and 5760 pounds at 40. If you want to figure out the load over a smaller area, then go by PSI, which is more like 30-50 if you are being conservative... and up to 90.

A table at 1 square inch a leg x4 with 200 pounds of food and table on it would be 50 PSI.

This has nothing to do with this, but I once was in a house where a guy saved the local newspapers for over 40 years and stacked them up in one of his bedrooms. The joists sagged about an inch over time and they had to split the papers up over a pair of dumpsters when the house was cleaned because the truck could not lift the dumpster with all of the papers. This was like 12x14x7 of solid paper. I used 30 pounds per cubic foot for paper for a calculation and it was like 17-18 tons.
 

Kmst80

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I remember Mythbusters testing the unwritten building rule that you shouldn't take out more than 1/3 of a joist to run pipes or other services.
They placed a full bathtub on a floor with joists and kept cutting the holes bigger and bigger. At the end they had to cut out all but 10 mm on top and bottom before the floor collapsed. Just shows you how overdesigned a well build house is.
 

JHSteepat

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I can’t speak for 2x12s, my joists were smaller and the floor was bouncy enough for me to worry about sag over a few years. I’ve had larger tanks (not 300g though) over the years, and never thought twice.

For me, other than cutting my finger in the process, given the cost of the tank, its inhabitants, and flooring repairs, the $200 or so I spent on the floor jacks were peace of mind.

(Now to hard-plumb the return pump after the blowout I just had where the soft tubing blew off the pump. Glad I was in the room as I don’t have automation running yet, to shut off: the screaming osmolator, the return pump that fortunately I had on 22%, and the overflowing skimmer that fortunately was just being broken in on a cycling tank. Less than a quart of water out of the sump but frightened me into considering keeping all electrical/control out of the cabinet. Happy I am working out the kinks before adding too much livestock.)
 

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