How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Stephen Cutler Your Own Question
Stephen Cutler
Stephen Cutler, General Contractor
Category: Home Improvement
Satisfied Customers: 2062
Experience:  35 years of troubleshooting construction, remodel, component & material failures. What to do next
12492335
Type Your Home Improvement Question Here...
Stephen Cutler is online now
A new question is answered every 9 seconds

I am building a 10X11 deck to support a hot tub. The hot

This answer was rated:

I am building a 10'X11' deck to support a hot tub. The hot tub will add about 100 PSF load to the normal live and dead loads. The deck will be free standing - not attached to the house. The property is sloped so closest to the house, the deck will be only 12" high and away from the house it will be no more than 36" high. I am planning 8" diameter concrete piers sunk 48" into the ground (below the frost line) to support 6x6 posts. I plan to support the deck with 3 triple-laminated 2x10 beams on three 6x6 posts per beam, The beams will sit on the post. The beams will 6-12" in from each end of the deck with a centre beam at 5'6". I plan to lay 2x8 joists with 12"OC supported with hurriance ties and direct screwed into the rim joists. Decking will be 2x6 laid on the diagonal. Total deck will be braced on all posts. Can I plan a party???
Hi and thanks for using JustAnswer.com.
You're good with the 6X6 uprights & the 6X10 carriers. The 2X8 at 12OC develop 100lb live load at 96" span. Your design yields 48" open spans.
see the table at:
http://www.southernpine.com/pdf/table11.pdf
I would expect this to develop at least 200lb live load.
The 2x6 on the flat is your weakest point. Basically you are spanning the 12OC with "joists" only 1.5" tall by 1.5" wide and "glueing" them together in groups of 4 = 2X6.
But because you are running them diagonally, you are extending the span to 16.9 inches. This reduces the 2x6's ability to resist vertical deflecting (although it is a great horizontal bracing).
Next you need to determine if 200lb/sqft is enough support.
10X11X200= 22,000 lb.
22,000 / 8.34 lb/gal = 2637.8 gal/ 7.48 gal/cuft = 352.64 cu ft / 110 sqft =3.2 feet deep max. People will displace about 1/3 of their body weight- so say 9 people at 200lb=1800 X .66 = another 1188 pounds in bodies = 142 gal = 18.98 cuft.
This presumes the full 10X11 deck surface is covered in 3.2 feet of water.
You can do the math to subtract a 12" perimeter for a safety factor, but to answer your question "Can I plan a party???", You Bet!, Party ON!
I hope that this information was helpful to you. If it was please remember to click "ACCEPT" on your screen to make sure that I am paid for my efforts. By clicking ACCEPT you are not giving up your ability to ask more questions pertaining to this subject, and I will be happy to respond to these as well. Please take a moment and leave feedback, it is very important!
If I exceeded your expectations, a bonus is greatly appreciated- it's easy to do
when you accept an answer. Or you can come back and add a bonus at a later date by using the "bonus" button at the top your question page.
Stephen Cutler and other Home Improvement Specialists are ready to help you
You will strengthen the 2x6 by laying them perpendicular to the 2x8 joists. This is because it shortens the unsupported span to 10.5" from 16.9 inches. You can run diagonal blocking for bracing. This blocking is in ADDITION to midspan blocking perpendicular to the joists to prevent vertical deflection from converting to lateral deflection. Thanks for your accept!
Customer: replied 7 years ago.
Much appreciated - the hot tub is 3600 lbs loaded and only holds 6 people max so we are good to go with a deck that will support 200 psf. thanks D