April 1, 2008 at 11:29 am · Filed under Barter House Framing, Barter House Images
Time and Pressure.
According to Red “Geology is the study of pressure and time. That’s all it takes really, pressure, and time. That, and a big god-damned poster”. Let our wall be the poster. We’re going to plant black bamboo (running - not clumping) in the seating wall which will provide a nice screen from our neighbors and hopefully some protection against stray golf balls. Some say the bamboo will break through the concrete block - others disagree. It took Andy Dufresne less than 20 years - how long will it take the bamboo?
March 31, 2008 at 7:20 pm · Filed under Barter House Framing, Barter House Images
The framers were back last week to implement the modifications proposed by Richard @ Kaydos-Daniels. We had most of the additional TJIs already on-site which saved on additional costs. The cross bracing you see in the pictures are to support the laundry room above. I’m also considering a cork underlayment throughout to help absorb some of the vibration and noise. Does anyone have experience with it?
Enjoy the photos.
March 20, 2008 at 5:39 pm · Filed under Barter House Framing, Barter House Delays
The TJI Certification Letter
March 20, 2008
Vernacular Studio
620 Tower St.
Raleigh, NC 27607
Attn: Brett Hautop, AIA
Re: Structural Review of Framing
Miller Residence
509 Davis Love Dr.
Chapel Hill, NC 27517
Dear Brett:
In reference to the subject project, please be advised that I performed a site visit on March 17, 2008 for the purpose of reviewing the installed framing, and responding to comments by *Firm* Engineering. Please review the following:
1. Double TJI’s at bearing wall locations above first floor Living Room
a. TJI’s to be same size + designation as existing
b. Additional TJI’s to span full length, but are not required to be “sistered” to adjacent TJI, however, 2nd floor decking shall be nailed to new TJI’s
c. Contractor to ensure that new and existing TJI’s are aligned directly under locations listed below
a. Location 1 : below wall separating master bedroom + bathroom
b. Location 2 : below wall separating Laundry Room from Master Closet
c. Location 3 : below wall separating Gina’s Study from Master Bathroom
2. Floor framing under second floor Laundry Room
a. Diagonal bracing at 24” O.C. to be provided at joist bays aligning with laundry room to reduce effect of possible vibrations caused by washing machine spin cycle operation
3. 2nd Floor ceiling framing : add 9 ¼” LVL’s at specified locations
a. Add to one side of existing double 2 x 10 beams
b. Remove ledger + cut ceiling joists to allow for insertion of new LVL beam
c. Use offset nailing pattern w/ 16d nails @ 12” O.C.
d. Re-hang existing joists using approved joist hangers
e. Locations
1. At beam above master bedroom
2. At beam above 2 story entry stairwell
4. Add 6 x 6 PTL columns at (4) corner window locations. See updated 4D/A5.02 (prepared by Vernacular Studio) for updated detail drawing.
Based upon my review of the installed framing, I hereby certify that the structural system, with the above modifications, is satisfactory with respect to the load and serviceability requirements of the NC State Building Code. This includes the 16” TJI 230 I-joists at 16” on center spanning approximately 23’-1”.
Kaydos-Daniels Engineers appreciates the opportunity to provide this Engineering Review and Certification for your use. Please do not hesitate to contact me if you have any questions, or if I may be of further assistance regarding this matter.
Respectfully,
Kaydos-Daniels Engineers, PLLC
March 13, 2008 at 4:05 pm · Filed under Barter House Framing, Barter House Images
Just when you thought it was over - the saga continues. It reminds me of a N.W.A. lyric and N.W.A. is just what I wanted to listen to when the drama of the TJIs returned. In our meeting last Thursday we came up with a plan to double up the TJIs that were supporting walls above them with TJIs or LVLs.
The following morning our builder sent an email explaining that he had his engineer (not the engineer who signed off on the house - here’s the he said/she said part) look at the living room and second floor beams and had some recommendations, but nothing alarming. Here is that recommendation - Does it sound alarming to you?
To Whom It May Concern:
A representative of *Engineering Firm Name* analyzed the following framing items:
1) Observed and analyzed the 16″ TJI 230 floor truss located above the family room.
The following conclusions and recommendations were noted:
1) Based on our observations and analysis, *Firm* recommends the following shall be constructed in general accordance with the attached diagram. (image below)
We appreciate being able to assist you during this phase of the project. If you need further assistance or require additional information please do not hesitate to contact us.
Sincerely,
*Engineering Firm*
The fax also went onto say:
The following items were not address (addressed) in our report. However, *Firm* recommends these items should be address (addressed) immediately (if) possible:
- Door opening (really referring to corner window) located at the rear left corner of the family room.
- Base (Based) on our observation and analysis, *Firm* recommends (the) installation of (1) 6×6 PT post (Note: or columns equivalent to a 6×6 PT post) or provide structural framing below the opening.
- The (1) 9-1/4″ LVL and (2) 2X10 beam(s) located above the 2nd floor room (Note: the room located above the family room).
- Based on observation and analysis, *Firm* recommends replacing the existing beam with (3) 9-1/4″ LVL’s to adequately support the anticipated loading conditions.
- The (3) 2×10 beam(s) located above the 2nd floor room (Note: the room located above the family room)
- Based on observation and analysis, *Firm* recommends replacing the existing beam with (3) 9-1/4″ LVL’s to adequately suppot the anticipated loading conditions.
So - needless to say we scrambled to get opinions from others to see if they felt this suggestions is warranted. The Engineer on the plans does not agree with this *Firm’s* comments, assuming the TJIs were installed per spec. We asked a former neighbor who happens to do commercial work and is a PE to comment on it. Here is what he said:
In the business, this is sounds like a classic case of strength (safety) vs. serviceability (deflection, bounce). As engineers, our primary responsibility is life safety. The information on your blog seems to say that your designer is a PE that has checked and double checked the framing for the design loading. I don’t think you have an issue with that. With serviceability we often get stuck between trying to minimize the owner’s cost and providing a quality product that performs well. Sometimes you just can’t win. Your particular situation could be debated for eternity.
Anyway, the TJI suppliers help the engineer by providing tables with both the strength and deflection information in the same place. Limiting deflection to L/480 is a pretty good limit (the same that I use for office space at 25 to 30 foot spans), but I can’t say it won’t bounce or deflect too much. I know very little about lumber. I can tell you that steel is bouncy and concrete is not.
If your contractor has noticed it, he could have a good point. If you want to “stiffen” the floor, I’m afraid the only real viable solution would be to replace the TJI’s with deeper sections, perhaps the next size up. My advice would be to find out how much that would cost you and then make a decision. I’m not sure I would worry too much about it, but I can’t say for sure how well this system will perform. I don’t think you have grounds to claim the designer engineer made a mistake - he designed to code minimum loads and industry standard deflections.
The blog conversation is very informative. Framing techniques are pretty standard, so I don’t expect there could be an issue with how they are installed.
We’re scheduled to meet on Monday morning with everyone (builder, architect, engineer on the plan) to come up with a safe, cost-effective, reasonable solution. I’ll keep you posted on the outcome.
~Clinton
