How Much Weight Can a Floor Support?
This is a common question asked by facility managers when contemplating a new file system or a heavy equipment addition.
Can your office floor handle the addition of a large filing system?
For example, a properly designed office floor can support 50 pounds per square foot. This may seem light, but this is 50 pounds over each and every square foot of floor space.
It does not mean that a 300 lb. lineman standing on one leg will fall through the floor.
A uniform load rating on a beam can easily be translated into what an equivalent maximum point load can be.
For example, a floor joist at 16” spacing’s that can carry 53 pounds per linear foot would translate into a 318 pound single point load at its center.
Location and configuration of heavy loads should be looked at on a case by case basis. For especially heavy loads it is recommended to have a structural engineer research the floor framing sizes and layout.
There may be workable solutions that will not require expensive modifications to the structure. These solutions could include: Spreading the heavy load over more than one floor joist. Strategically locating the load near the end of a joist.
Careful assessment of the end connections would be advised though. Limiting the loading on the remaining areas of the floor.  Another consideration to keep in mind is the effect of the heavy load on additional deflection.
Even though the additional deflection may be within code limits, the impression of stability to the occupants must also be a consideration. Understanding the structural limitations of floor systems is just one of the ways ADS Engineering can help is assessing existing buildings. To see some other ways ADS can help, check out our website @ https://alleghenydesign.com/structural-engineering
Thanks for reading!
~Dave
Written by David Simpson, P.E., SECB, MBA, President, Principal Engineer
David Simpson’s experience includes over 30 years in structural design and project management for industrial, commercial, institutional and nuclear/chemical facilities utilizing steel, concrete, masonry and wood. His accomplishments include design and construction administration of health care facilities, hotels, schools, shopping centers, aircraft hangars, numerous retail facilities and several forensic engineering assignments. He has professional registrations in D.C., Maryland, Ohio, Pennsylvania, South Carolina, Virginia and West Virginia. Simpson graduated from the West Virginia Institute of Technology with a bachelor’s degree in civil engineering and an MBA from West Virginia University.
Amazing! You know I love your blog!!!
I have an 800 pound “free motion” weight machine. The base is angled in a wide “V” shape. I wanted to turn a second floor bedroom into a gym. The house was built in 2014. It has real pine wood floors. Will the floor support this king of weight of would I expect it to land in my kitchen at some point.
A simple trick would be place your Weight Machine on a 8 foot x 4 foot 3/4 inch piece of plywood. This would distribute the weight over a big area…\
800/32 = 25 LBS/FT^2
If you weigh 200 LBS
1000/32 = 31.25 LBS/FT^2
This is much below the 50 LBS/FT^2 load designed in most homes.
Note: This was a trick they did back in the 60’s and 70’s when everyone had a waterbed.
The designed a large base that spread the weight of the water over a large area.
In some models the actual (load) weight per square inch was much less than the 4 to 6 point load on a standard king size bed.
How much weight can a 11 7/8″ X 1 3/4″ X 20′ wooden I-Joist hold
I have a 2nd story rec room, measuring 24×18 in an all brick house built in 2011. The rec room is the only room on the 2nd floor and contains attic access and a full bath.
I would like to put a 12×6 ft billiards table, which stands on 8 legs and weighs approx. 2755 lbs in the center of the room.
What is the likelihood the floor will support the weight, and would it benefit me to place plywood, or something beneath the table to better distribute the load?
I plan to have an engineer out to inspect the premises before installing the table, but am just looking for ballpark opinions at this point.
I purchased an office safe weighing 202 lbs. with 4 rolling casters. The floors in our home are the old Pergo type. .(softer than the new laminate flooring these days). There is a crawl space in this home. Will the floors support or perhaps I need to put
the safe on plywood or tile? Thank you very much for your help.
I have recently purchased a large fish tank, when filled will weigh around 516kg. Would this be safe in a first floor bedroom spanning 2 joists?
If i give you the floor joist size and the thickness of the plywood and over all demensions of the platform. Can you tell me what the load capacity would be on it
Our engineered floor trusses are 16″ on center, 9″ tall and 2.5″ wide. They span 13′ between supports. Can I install granite in my 8′ by 5′ center island?
How much weight could be put on a concrete floor with 250 psf design? Would a 4,000 lbs. load that is 62″ x 18″ (footprint) be ok?