2x6 floor joist on 1950's home

[scuba_dave]

I could have sworn they were 2x8 on the 2nd floor, but no they are 2x6 16" on centers. Now these are closer to a true 2x6 measuring 5 3/4". I have no idea of the type of wood, it is closer in grain then wood these days
2nd floor has been in use as a 2nd floor for some time
From the looks of the small bedroom & main room were original from the 50's. A bathroom was added at some point on one end above the 1st floor bath

Longest span is 13' 6" which is in the main room (1st floor ceiling). Most of which is a knee wall storage are on the 2nd floor

From any span calc I can see usually 10' is the max span these days. Anyone have a good link to a span calc?
Max 11' with 30/10 load & L180
- ALmost 12' w/Hem fir!!

What is "normal" for a live/dead load for 2nd floor bedroom? Deflection I can expect?

Ceiling in main room is fine on the 1st floor. It does need to be scraped down (popcorn) & repainted

The bed will sit across an area that is directly supported by 2 walls on the 1st floor. Furniture will be against the walls. So the only weight will be us walking - I'm about 165 lbs soaking wet, wife - can't ask!!

[suemarkp]

Whatever span tables you are using seem to be correct. Usually, an upstairs bedroom is 30 PSF live, 10 dead. If the wod underneath the 2x6's is sheetrocked (i.e. finished ceiling below), I'd like the deflection to be no more than L/360. I really prefer floor to be stiffer than that, but you'll be lucky to just not have the plaster below crack with this span of 2x6's.

The knee wall helps, as there may be a lower load of stored materials there (good place for pillows, bad for cement block storage).

[CR500]

All things being equal, the strength will go as the base times the height cubed.

b x (h)^3
------------ = I
12

So a 2" x 6" dimensional board will be 25% weaker than one that measures 1.5" x 7.25"

I had to write the equation above backwards to get it formatted correctly in the posting.

[scuba_dave]

OK, Thanks - I figured they were undersized for the main room. With a finished height floor upstairs there is no way to change this. 2nd floor bathrooms, walk in closet, small bedroom & about 70% of the main room will be OK.
I don't anticipate any added problems, it's existed this was for 50 years. The 1st floor ceiling are going to be cleaned up (popcorn) & repainted once the 2nd floor is completed

So most are fine, just the main room drops to L180
When I brought in the 1/2" sheetrock (16 sheets?) for the 2nd floor I stacked it against one wall on edge. That was too much weight in one area & the 1st floor ceilings in that spot cracked

The Master bedroom on the 2nd floor does not have any "unsupported" dividing walls on the 2nd floor that pur pressure on the floor. Actually the 2nd floor knee wall is unsupported across the 13' 6" span on the 1st floor
It doesn't show any cracks on the 1st floor ceiling, and is only used for light storage. Heaviest item would be me crawling thru

Thanks again