# Joist Size for Hot Tub Deck

by John Stuart
(Calgary, AB)

I'm struggling to find the appropriate materials for the lower portion of a 2 tier deck that will be supporting a hot tub.

The lower deck structure is 10'x10' ledger to beam construction. So far I have designed the beam running 9' parallel with the house with 3 sonotube footings, both outside footings are 1' in from the ends of the beam, with the middle footing directly supporting middle section of beam.

I have calculated the biggest load area in the middle as 22ft squared (4'x5.5'). Based on articles posted at this website I went with a deck load of 100psf to hold the hot tub. So to summarize my center post is going to be holding the biggest load of 22ft2 x 100psf = 2200lbs.

I've had no problems calculating my footings (10" diameter and 4' depth) and post (6 x6)....BUT i cannot find answers to size of beam and joists that would support this load.

I'm using prem pt lumber thats made from spruce... HOW CAN I FIND ANSWERS TO THESE SPECIFIC ENGINEERING QUESTIONS?