Originally Posted By: jmyers
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Does anyone know what the maximum distance a 2 X 12 can span unsupported?
Joe Myers
Does anyone know what the maximum distance a 2 X 12 can span unsupported?
Joe Myers
Originally Posted By: chorne
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Hi Joe,
That depends upon the framing situation, O.C. and what it is supporting
above if anything ??
What is the situation?
Carla
Originally Posted By: mbailey
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Joe,
That depends on whether it is floor joist, ceiling joist, rafter etc...
Wood species, grade of lumber, loading and spacing.
Please provide some details.
Mark Bailey
Stonegate Property Inspections LLC
Ponca, NE
Originally Posted By: jmyers
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Thanks to the quick responses. It is block walls, 2 X 12 recessed into the walls. The only weight that I know of on the joists themselves is whatever is on the floor above it. They were spanning 19 feet 4 inches and that does not include the amount of joist that was recessed into the block. The joists were 16" OC.
The style is a row house, the design would be a split level. This was the lowest floor in the house and was a crawl space. The joists themselves ran from left to right as opposed to front to back.
The roof was a flat roof design. None of the walls in this house were load bearing. The only weight they needed to be able to support were the wall and whatever was placed on the floor above it.
Thanks again,
Joe Myers
Originally Posted By: mbailey
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Assuming 16? OC, 40lb live/ 10lb dead load and that the lumber is Hem/Fir Grade 1 or 2 - should span 19?1?. Keep in mind that is with Canadian lumber (yes, it makes a difference) US lumber will only get you 18?10?.
Anything other than Hem/Fir for the lumber and the span decreases quite a bit.
Lot of assuming on my part ? hope this helps.
Mark Bailey
Stonegate Property Inspections LLC
Ponca, NE 68770
Originally Posted By: rmeyers
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Joe,
Same assumption, 40lb live load / 10lb dead load, 16" OC, The International Residential Code for One and Two Family Dwellings (2000) Table R502.3.1(2) indicates the following:
Douglas fir-larch SS (Select Structural) 21-1
Hem-fir SS 19-11
Southern pine SS 20-9
Southern pine #1 20-4
Spruce-pine-fir SS 19-6
Absent any grade markings to verify these species and grades, they better be some pretty good looking 2x12's. Otherwise I would say it was questionable.
Stay on the safe side!
--
Russ Meyers
Originally Posted By: jmyers
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Russ,
I did not see any grade markings on them at all. I recommended they call in a licensed contractor for evaluation just to be on the safe side.
I did not see one broken or stressed joist out of a good two dozen. No twisting, turning, cracks, bowing....I do mean nothing.
From what you are saying they called it pretty close in this case. This house is over 45 years old so I would think if it was going anywhere it would have already done so.
Joe Myers
Originally Posted By: jhagarty
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Deleted
–
Joseph Hagarty
HouseMaster / Main Line, PA
joseph.hagarty@housemaster.com
www.householdinspector.com
Phone: 610-399-9864
Fax : 610-399-9865
HouseMaster. Home inspections. Done right.
Originally Posted By: jmyers
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Thanks Carla, Mark, Russell, Joe.
I appreciate the help, especially the span table.
Joe Myers
Originally Posted By: rmeyers
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Joe,
At the time this house was built they were probably still using larger dimension lumber (prior to downsizing approx. 35-40 years ago, I can remember using!) The grading standards have also been adjusted at least once since downsizing to take into account the smaller and lower quality timber being harvested from the "quick growth" forest.
If the joists are embedded into the masonry they may also be gaining some strength from that "connection" increasing the effective span slightly.
May need one of our structural engineer members to explain that concept in more detail. (Faint memory from structures class!!)
Did the floor feel solid from above?
As you stated, sounds like it should be OK if not showing any problems after this many years.
Let us know if the contractor disagrees with our analysis.
--
Russ Meyers
Originally Posted By: jmyers
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Russell,
I jumped on it (around 210 to 215) and it did not feel soft or spongy so I would have to assume it was ok. Like I said, no damage anywhere. I have seen new floors in much worse shape. Cracks, bowing, splits.....
I am not sure the client will take my advice but I always recommend they ask for the professional opinion just to save my butt.
Thanks for the help. Maybe I really should read some of those darn code books! HA
Joe Myers
Originally Posted By: mpetner
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Joe,
I'm curious why you're even asking that question. Was there something or some existing condition that would cause you to question whether or not that joist was adequate?
In any case, if you want to get into the particulars, maybe you should check with that local township. Not all governing agencies have adopted the 2000 International Residential Code. Alot of municipalities still have their own (although most of it is very similar to what you'll find the the Int. Res. Code). I know that Philadelphia hasn't adopted the 2000 Int. Res. Code. yet.
Was the joist improperly notched or drilled for plumbing or electrical wires? Usually drilling or notching in the middle third is not good. I doubt the concrete block had any cantilever effect to stiffen the beam, but was there atleast 3 inch bearing into the concrete wall? Better even if it had a half inch or so clearance on top and sides at point where it entered the masonry. If any of those conditions weren't met, maybe the integrity of the joist was compromised, making your evaluation easier.
Then again, if it's been there that long, then maybe it's ok, as was previously said ???
Originally Posted By: gbeaumont
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Hi Michael,
welcome to our message boards, I hope that you find us interesting and informative, do you do Home Inspections as part of your PE business ?
It is nice to see a PE here as although we are generalists, we do tend to ask an awful lot of technical questions about what we see on a day to day basis, as you will no doubt see from our posts we are a very information hungry bunch.
Regards
--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466
Inspection Depot Education
gbeaumont@inspectiondepot.com
"Education is a journey, not a destination"
Originally Posted By: jmyers
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Hello Michael,
It was more from a disbelief standpoint. I could not believe with that long of a span I found nothing wrong with any of the joists. It was not possible to know how far they were recessed into the block. They were well placed with no visible room between the joist and the block at all.
There were absolutely no notches, holes or anything else on any of the joists. I was enveous of the job they did on those floor joists. I have not seem workmanship like that in so long I almost forgot what it looked like!
Thanks for helping and welcome to NACHI. It is nice to have a PE onboard. Just watch out, we may question you to death!
Joe Myers
Originally Posted By: mpetner
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Thanks to all for the warm welcome. This is a great website. I?ve spent alot of time on it already. Gerry, I?m not actively performing home inspections yet, but I think that?ll change soon enough. I?m currently in the water/sewer business right now working for the city.
Talk to you all later.
Originally Posted By: jremas
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Michael P, good luck once you get started. I think you can easily target the Phoenixville area as I hear they are in desperate need of quality home inspectors in that area!! Move north!
Sorry Joe M, I just had to bust ya
--
Jeff Remas
REMAS Inspections, Inc.
Northeastern PA & the Poconos
www.NEPAinspector.com
570-362-1598
Originally Posted By: jmyers
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Jeff,
Once I am down in Florida full time you are correct they will need a good inspector around here full time!
Especially up towards to Pocono's! (just ribbing you back)
Joe Myers
Originally Posted By: Ben Gromicko
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Just found this today.
http://www.cwc.ca/design/design_tools/calcs/SpanCalc2002
–
Benjamin John Gromicko
Vice-President,
PEACH Inspections
NACHI & ASHI Member
Originally Posted By: gbeaumont
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Hi Ben
That is a realy good link
Many thanks
Gerry
--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466
Inspection Depot Education
gbeaumont@inspectiondepot.com
"Education is a journey, not a destination"
Originally Posted By: Richard Stanley
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“There was nothing wrong. It wasn’t damaged. twisted. etc. It has been there for 45 years. ‘I recommended further professional inspection’”…You were hired to tell your client what, if anything, is defective about the building/home they are about to buy. If you recommend 'further inspection for something that isn’t defective, what do you do for things that are defective. It would be easier on you to tell the clients on the phone to just send you xx so that you can tell them to hire an engineer, electrician, plumber, HVAC tech., etc. That is the kind of action that will ruin this industry. I realize that most of the hi's just want to fill up their reports with disclaimers and cover your <b>a% statements, but, knowing what you are doing and saying so is a lot easier and saves alot of paper. I doubt that referring this will enhance your reputation. They will tell their friends" he told us to hire someone else and they told us there was no problem". I don’t believe you are required to know what the code was 45 years ago or now.