live load - alf living room
live load - alf living room
(OP)
I have an existing assisted living facility renovation where flat wood roof trusses designed for 40 psf live load will be use for the floor system for a second story addition. Part of the addition will be bedrooms and other part common areas (living room) although not specifically addressed in my state code and/or asce 7 it seems 40 psf would be appropriate for an ALF bedroom but 100 psf would be needed for a common room any thoughts? Appears I may have to require the existin trusses be replaced just for this reason and/or worse try to modify or augment the floor system for additional strength...any thoughts? Could 40 psf be justified as adequate for this use?






RE: live load - alf living room
I once accomplished a significant upgrade through sheathing existing trusses in plywood to create box beams. You may want to try to think outside the box for this one...
RE: live load - alf living room
RE: live load - alf living room
RE: live load - alf living room
RE: live load - alf living room
Mike McCann
MMC Engineering
RE: live load - alf living room
I'd be interested to know where you read that. It would lighten a fair amount of loads.
RE: live load - alf living room
Mike McCann
MMC Engineering
RE: live load - alf living room
TABLE 16-X: Values for Occupancy Importance Factor I
I
Type of Occupancy
SNOW
1. Essential facilities. 1.15
2. Any building where the primary occupancy is
for assembly use for more than 300 persons
(in one room). 1.15
3. Agricultural buildings, production
greenhouses and other miscellaneous
structures. 0.9
4. All others. 1.0
16-04-
RE: live load - alf living room
Mike McCann
MMC Engineering
RE: live load - alf living room
RE: live load - alf living room
RE: live load - alf living room
Actually we did a load study years ago and we came up with about 75 psf, but try explaining that to a judge or jury. I would go with the 100 psf.
RE: live load - alf living room
RE: live load - alf living room
"Added a continuous steel strip to the bottom cord on each face, so in the end this was under the plywood. The same fastening for the plywood to timber added to the placement "tacking" which was done to put the steel in place. It was an adaptive job, but the result was easy to construct. The only tough part was that we required the contractor to have the steel strips under tension when fastened. They fastened one end and then used a pully at the far end to draw the strips towards the opposite end."
Nice idea. I'll keep that in mind. I have added an additional flat 2x4 to the bottom chord before. Had a dropped ceiling so the extra depth was not an issue.
RE: live load - alf living room
I really loved practicing in New Zealand, where it is all performance based code with detailed review by the city. Show them what you're doing, show that you did the calcs, and build whatever you want. No mandatory anything, other than loading, just make it safe and practical. Yes, the same flexibility is available here, but it is not really practical. The building permit process practically grinds to a halt if your job isn't 100% typical.