• Welcome to The Building Code Forum

    Your premier resource for building code knowledge.

    This forum remains free to the public thanks to the generous support of our Sawhorse Members and Corporate Sponsors. Their contributions help keep this community thriving and accessible.

    Want enhanced access to expert discussions and exclusive features? Learn more about the benefits here.

    Ready to upgrade? Log in and upgrade now.

Search results

  1. D

    Joists and Girder span tables for decks questions (2006IRC)

    Treating lumber does not lower its' strength, incising lumber does but on the east coast and in SYP you don't see incised lumber. Under the same conditions the allowable spans for pt are identical to the allowable spans for untreated lumber. The base design values are reduced for wet service...
  2. D

    Joists and Girder span tables for decks questions (2006IRC)

    I agree. 2006IRC, it should be on a full perimeter foundation or design is required.
  3. D

    Joists and Girder span tables for decks questions (2006IRC)

    That's a good bit of the reason I wrote those calcs, to play "what if". It is a good idea to follow that preliminary design up with rktekt 1's advice. In performing the three checks in my calc, or in any rectangular beam sizing program, the calculations account for the shape of the beam, its'...
  4. D

    Joists and Girder span tables for decks questions (2006IRC)

    Interesting switch, 2@2x10 vs 3@2x8 The moment of inertia used for deflection calcs is bd^3/12 for a 2x10- (1.5"x 9.25" x 9.25" x 9.25")/12= 98.93"^4 ...at 2 ply 198"^4 for a 2x8 moment of inertia is 47.63 ... at 3 ply 143"^4 The 2 ply 2x10 is stiffer, there's more wood in the right place.
  5. D

    Joists and Girder span tables for decks questions (2006IRC)

    The span tables in DCA6 are based on wet service and incised lumber for west coast species. A triple #2 SYP 2x8 girder supporting one end of 12' joists, 1/2 the load, have an allowable span of 8'1". Those tables limit to l/360 deflection. hmm wonder why on a deck?
  6. D

    Joists and Girder span tables for decks questions (2006IRC)

    Thanks Gary, I hadn't read all of this weeks's mail. This was forwarded from the ALSC Thursday. They have the FPL's letter available, but it sounds like dotting I's. One thing to play with in the calc is read Gary's link, change the design values according to what it is saying and notice...
  7. D

    Joists and Girder span tables for decks questions (2006IRC)

    well, what a day for this question. Pine strength values were scheduled for final review yesterday, I haven't heard the details yet but the strength is looking to drop 30%. Also, wet service design, like a deck, should include a 15% strength drop as compared to the design values used in the...
  8. D

    Virginia Uniform Statewide Building Code USBC

    Skip, please consider putting that link in your signature line.
  9. D

    Great Room framing on single family residence

    ...pick apart from afar... I hate it when a good sentence goes bad.
  10. D

    Great Room framing on single family residence

    I've always thought that if you turned a busload of carpenters loose in the Taj Mahal they'd have it thoroughly picked apart in an hour or two. With pics on the net we have the opportunity to pick apart from apart and assume what we will. Opens up more possibilities for discussion. It looks...
  11. D

    Big Brother is Watching

    Yup, she tilled in the old beds today and has been to one of "those" sites again. Strawberries on the big banner. Yeah they look good, no way they're real.
  12. D

    Great Room framing on single family residence

    Now that you mention it :D The rafters appear to be on a flatways 2x~10 plate that is nailed atop the cj's with no rim or perimeter blocking. It's sort of similar to a situation we were discussing a few months ago.
  13. D

    Great Room framing on single family residence

    I assumed that was an lvl at the laundry rim. There is no hinge, not that it's right, that is a row of blocking midway on the tall wall. The rafters sitting on a raising plate are not well tied, the hip area is also untied.
  14. D

    6x14 fir, span

    Thanks Gary, WSDD, I scrambled it up there somewhere... Wood Structural Design Data; Wood Structural Design Data Revisions Just from a quick look, assuming dougfir in #2 heavy timber it would be good for around 450 PLF or ~7000 lbs uniformly distributed.
  15. D

    6x14 fir, span

    On the awc.org website you can download the WCDD manual, there is a good set of instructions near the beginning. It would give an answer as acceptable as using a table in an LVL book.
  16. D

    How does your home measure up?

    No, I experimented on my own. It won't fail structurally, blessed be the unintended load path, but it does show there are some laws you just can't break. The rest is 80's BOCA/CABO and I have no problem with that. I could understand most of it.
  17. D

    Hurricane Ties/Clips

    JAR, were you testing to see if keystone knew his mike was on? :D We liked the heavy banding that engineered items came strapped in.
  18. D

    Hurricane Ties/Clips

    No doubt about it, "engineered" building components have better backup behind them than traditional methods, kind of funny when you think about it. I do use hurricane clips here in a typical dimensional lumber or truss roof, just pointing out that it is not the only way. The code lanuage in the...
  19. D

    Hurricane Ties/Clips

    A nail is a dowel type connector, there is an adjustment factor for toenail configuration. The awc.org connections calc gives the same output as the tables in the NDS for typical generic connectors... nails, screws, lags, smooth dowels, etc. Manufacturers provide tables for proprietary...
  20. D

    foam insulation, no venting

    As I read this I'm reminded of Plato's allegory of the cave. Many of us are describing the shadows on the wall. We really need to focus on science rather than opinions, even when those opinions are coming from those in some position of authority. I do appreciate your following up with the ICC...
  21. D

    New and confusing IRC 1102.2.2 R=30 or greater

    IF the area is less than 500 square feet THEN the insulation level can be reduced to R30. Burning foam can be toxic but I suspect the contents would really be the culprit in that scenario.
  22. D

    Stacked lumber

    Globe trekker, I don't really even care for the 2x2's with osb in between and I prefer trusses made with 8x10's but if it pencil's out it is a viable option. In between chugging a gallon of goLytely today I had lots of time in the reading room and was thumbing through back issues of JLC. The Feb...
  23. D

    foam insulation, no venting

    On the current job concern about wildfire was a big driver but windblown snow and rain are mentioned in one of Lstiburek's articles. In most cut up and cathedral ceilings there is effectively no ventilation to begin with, the space is too small and often blocked. I've gone over the rafters with...
  24. D

    foam insulation, no venting

    Sifu, would you mind writing back for an interp of the '09 and '12 codes on this issue? We have been having open cell foam applied to the underside of the roof sheathing without problems thus far. My Dad was building unvented foam covered plank and beam roof assemblies in the 60's and 70's...
  25. D

    Stacked lumber

    I understand the situation. I strongly suspect you are making the right call, but for the wrong reason. That is what I'm working on. "They stacked lumber thus they need an engineer" is incorrect. They overloaded an inadequate 2x6 joist, or, they tried to create a structural 2x12 out of two 2x6's...
Back
Top