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Andy Margeson
10-01-2011, 12:58 PM
I have a new house built to code. To make more room in my shop, I want to move my commercial weightlifting machine into my 3rd bedroom, which has a standard joist/plywood floor. The
machine footprint is 4' x 4' and, with the weights, I estimate that it weighs 500-600 lbs. Since I weigh 240, the floor loading might be around 800 lbs when I am using it. Will this overload the floor?

Bruce Wrenn
10-01-2011, 9:11 PM
40 pounds per square foot is standard design loading on most residential floors. So we are looking at 800/16=50 pounds per square foot. Without your weight, you are looking at 600/16=less than 40# psf. Water beds tend to weigh about 40# psf. You may want to build a platform with 2 X 6 joist running perpendicular to floor joist to span more joist, and thus spread the load.

Joe Watson
10-02-2011, 12:09 AM
Is it a "real" bedroom - or an attic or loft converted into a bedroom ?
If it was an attic converted, i personally would do more research on how the "floor" joists are constructed. If it was a normal bedroom then i would go by current floor load (or since Bruce Wrenn already did the math, follow that). You could also double check at your local building inspector, floor loads might be different around the country... If they have the time, they might stop out and give you a curtice look and their opinion.

_

Andy Margeson
10-02-2011, 1:41 AM
Is it a "real" bedroom - or an attic or loft converted into a bedroom ?

_

It's a real bedroom on the first floor in the corner, so it rests on two outside foundation walls. If I locate the weight machine in this room, I'll put it about 2' from the corner of the outside walls on each side. Since I am an economist and not an engineer, I'm thinking about it this way. When we have a party, four guys that probably weigh 800 lbs. together stand in a four foot diameter circle talking and we don't go
through the floor. Probably something wrong with this logic.

Kevin W Johnson
10-02-2011, 2:18 AM
It's a real bedroom on the first floor in the corner, so it rests on two outside foundation walls. If I locate the weight machine in this room, I'll put it about 2' from the corner of the outside walls on each side. Since I am an economist and not an engineer, I'm thinking about it this way. When we have a party, four guys that probably weigh 800 lbs. together stand in a four foot diameter circle talking and we don't go
through the floor. Probably something wrong with this logic.

It'd be real easy if you had a basement.... However, you could still add additional bracing under that area in the craw space. Doing so would eliminate any potential saging of the floor, or worse.

Sam Layton
10-02-2011, 9:56 AM
Andy,

You say your new house was built to code... Just remember "code" is minimum standards...

ben searight
10-02-2011, 10:02 AM
It really depends on the layout of the room, span of the floor joist, other loads in the room, etc. The 40 psf is an unfactored live load, it is not the actual structural capacity of the floor. I highly doubt you will have a problem, as most residential structures end up over-designed, but without knowing the layout, dimensions, other loads, and framing member sizes, it is impossible to calculate the deflection of the floor.

Richard Jones
10-02-2011, 10:04 AM
Andy,

You say your new house was built to code... Just remember "code" is minimum standards...

From an inspectors' standpoint, all I can add to that is a big AMEN............

Rich

Lee Schierer
10-02-2011, 12:54 PM
For less than the cost of your insurance deductable you can hire a structural engineer to review your siyuation and give you an answered based on fact and calculation. Without details of how the foors and walls are actually structured any ideas offered sight unseen are purely speculation.