medeek Posted November 28, 2015 Author Report Posted November 28, 2015 Valley Sets are here: Proceed with caution though I just put it together so it is still a bit rough around the edges. Further testing and refinement is necessary but it seems to be working fairly decently. Currently the main roof plane and two points need to be selected rather carefully I'm not sure I can do much about that, if not I will need to document in some detail how to use this function.
Marc Posted November 28, 2015 Report Posted November 28, 2015 The world of trusses is turning out to be a whole lot more complicated than I ever previously imagined. Marc
medeek Posted November 29, 2015 Author Report Posted November 29, 2015 I've addressed a few bugs with the valley set algorithm and tested it in as many configurations and orientations as possible. It it more solid now. I suggest downloading the latest version of 1.1.7 that I just uploaded to the server. Note that the plane of the main roof that is selected needs to be a rectangular shape at the moment to properly register (1st point selected). I usually just select the top face of one of the top chords of the trusses. The second point should be at the centerline of the last truss of the secondary roof line and at the ridge (peak) of this truss, the third point is also at the ridge (peak) but at a point towards the main roof. I really need to put the manual together to document this feature and how to use it, or at least a video. I also updated the geometry algorithm slightly so that it adds additional verts a 48" o/c when the valley trusses get too large. This is keeping in line with standard practice on these types of valley sets. I can also make this an input if someone requests that it be such.
medeek Posted November 29, 2015 Author Report Posted November 29, 2015 The world of trusses is turning out to be a whole lot more complicated than I ever previously imagined. Marc This update was not that complicated (valley sets) other than trying to figure out how to place the set based only on a plane and two points. Obtaining this information and then figuring out the math and code to compute the distance between the bottom of the first valley truss where it rests on the main roof plane and the peak of the secondary roof line was the slightly painful part. The actual geometry of the valley set was surprisingly easy to code. The real challenge will begin when I try to add some hip sets, I may push that out for awhile.
medeek Posted November 29, 2015 Author Report Posted November 29, 2015 Here is an example of a large valley set with a Monopitch Primary Roof and a Common Secondary Roof. Notice the pitch of the monopitch roof is 6:12 while the secondary roof is 12:12. Rather than calculate the overhang for the secondary roof it is just as easy to to trim the truss tails back and adjust the fascia so that it lines up with the fascia of the main roof after the fact. Even with all the automation of certain tasks there is still a good bit of manual editing required when complex roof lines are involved however I find that SketchUp has a very intuitive interface for trimming solids and once the basic geometry is there the rest is usually not too much trouble.
Marc Posted November 30, 2015 Report Posted November 30, 2015 In actual practice, the primary roof is decked out before the secondary roof is placed upon it, correct? Marc
medeek Posted November 30, 2015 Author Report Posted November 30, 2015 In actual practice, the primary roof is decked out before the secondary roof is placed upon it, correct? Marc Correct, that is why I have a sheathing offset (user input) that can be entered if you are selecting a face from the top chord of the truss instead of the sheathing. With the main roof sheathing:
medeek Posted December 7, 2015 Author Report Posted December 7, 2015 Version 1.1.8 - 12.07.2015 - Added Gable Rafter Roof. - Advanced options enabled for gable rafter roofs (sub-fascia, outlookers, sheathing, and rakeboards). - New submenu item and toolbar icon added for rafter roof type. - Plugin divided into multiple files for ease of management. Structural outlookers for this type of a roof are still somewhat of a question. If they are horizontal it makes sense to notch the gable rafter but what if they are vertical?
Jim Katen Posted December 8, 2015 Report Posted December 8, 2015 Structural outlookers for this type of a roof are still somewhat of a question. If they are horizontal it makes sense to notch the gable rafter but what if they are vertical? Either don't use vertical outlookers or drop the gable rafter.
medeek Posted December 9, 2015 Author Report Posted December 9, 2015 Version 1.1.8 - 12.08.2015 - Structural Outlookers enabled for gable rafter roofs (vertical & horizontal). Notice in this case I have left the gable rafter in place but notched clean through it, so essentially it is blocking. However, I have also given the option for removing the gable rafter entirely. You will also notice that the gable rafter is the same depth as the outlookers, when you choose "CUSTOM" for the gable end rafter it allows one to specify the depth of this rafter. When structural outlookers are used in a vertical orientation it is common practice to have them bear directly on the double top plate of the gable wall (balloon framed to roof). If there is some configuration that is standard in your neck of the woods that I am missing please let me know. I am currently providing three different configurations for the gable end rafters. I think I am ready to now attack the gable rafter roof with glulam beam.
Marc Posted December 9, 2015 Report Posted December 9, 2015 I know outlooker only as the horizontal member fastened to the seize (spelling) on one end and the rafter tail on the other. It provides the nailbase needed for the soffit panels. I don't what's meant by vertical outlooker. Marc
Jim Katen Posted December 10, 2015 Report Posted December 10, 2015 I know outlooker only as the horizontal member fastened to the seize (spelling) on one end and the rafter tail on the other. It provides the nailbase needed for the soffit panels. I don't what's meant by vertical outlooker. Marc In this case, outlookers are the boards that support the barge rafters. The outlookers generally start at the first real truss, extend out past the gable-end truss, and project out to support the barge rafter. Where I live, these are generally 2x4s laid flat. I believe that when Nathanial is talking about vertical outlookers, he means that the 2x4s are placed upright instead of flat - to make them stiffer.
medeek Posted December 10, 2015 Author Report Posted December 10, 2015 Version 1.1.9 - 12.10.2015 - Added Gable Rafter Roof with Glulam Beam (all advanced options enabled).
Marc Posted December 10, 2015 Report Posted December 10, 2015 I took a look at your site. Do the plans come with a stamped engineering cert? Marc
medeek Posted December 11, 2015 Author Report Posted December 11, 2015 Here is quick model of the wall framing associated with a gable roof with a glulam beam: Beam Pocket with 6x6 post: Gable wall and eave wall intersection: Overview of Model:
medeek Posted December 11, 2015 Author Report Posted December 11, 2015 I took a look at your site. Do the plans come with a stamped engineering cert? Marc The short answer is, they can. However, I am currently only licensed in Washington and Utah so I can run the engineering for plans in only these states. Other jurisdictions would require a locally licensed engineer to review the plans and stamp them if required by the building department. Typically with my plans I rarely have someone buy them as is, even though I post them on the web site. Usually someone wants to do a garage design or house that is similar to one of the plans but requires modification, from there it becomes a custom job with a new planset and new engineering (site specific).
medeek Posted December 12, 2015 Author Report Posted December 12, 2015 With I-joist roofs don't think I would model in any of the web stiffeners, otherwise the model gets too heavy, same goes for small fasteners and hangers. I haven't even considered the option yet with the rafters resting on top of the beam (dropped ridge). The I-joist manufacturers do not allow notching at the top end and therefore a beveled bearing plate or strip is required with web stiffeners on both sides of the I-joist. Their detail shows a strap across the tops of the I-joists tying them together across the beam, I'm pretty familiar with this detail from some local jobs I've done recently. However, I'm also wondering about the beveled strip on top of the ridge beam, how is it made, thickness at the butt etc... With common sawn rafters how would you typically handle a dropped beam? Would you use a beveled strip or would you apply a birdsmouth cut at the ridge? I think I've seen both details but what is the preferred method if there is one. The problem is I'm not out in the field enough so I never get to see this stuff actually go together very often.
medeek Posted December 13, 2015 Author Report Posted December 13, 2015 Added dropped beam options for Gable Rafter Roof with Glulam Beam: Notched rafter and Bevelled plate.
Jim Katen Posted December 13, 2015 Report Posted December 13, 2015 . . . However, I'm also wondering about the beveled strip on top of the ridge beam, how is it made, thickness at the butt etc... With common sawn rafters how would you typically handle a dropped beam? Would you use a beveled strip or would you apply a birdsmouth cut at the ridge? I think I've seen both details but what is the preferred method if there is one. I've never framed a roof with I-joists myself. Every time I've seen it done, though, the I-joists rest in hangers on the side of the beam. If I had to make a beveled top strip, I'd do it just as I would for sawn rafters, with a table saw. I'd try to leave about 1/8" at the bottom ends of the strip because it's messy to taper down to nothing.
Marc Posted December 13, 2015 Report Posted December 13, 2015 With I-joist roofs don't think I would model in any of the web stiffeners, otherwise the model gets too heavy, same goes for small fasteners and hangers. I haven't even considered the option yet with the rafters resting on top of the beam (dropped ridge). The I-joist manufacturers do not allow notching at the top end and therefore a beveled bearing plate or strip is required with web stiffeners on both sides of the I-joist. Their detail shows a strap across the tops of the I-joists tying them together across the beam, I'm pretty familiar with this detail from some local jobs I've done recently. However, I'm also wondering about the beveled strip on top of the ridge beam, how is it made, thickness at the butt etc... With common sawn rafters how would you typically handle a dropped beam? Would you use a beveled strip or would you apply a birdsmouth cut at the ridge? I think I've seen both details but what is the preferred method if there is one. The problem is I'm not out in the field enough so I never get to see this stuff actually go together very often. Haven't installed any dropped ridge beams before but if I had to, the first thing to come to mind is to simply let a common ridge board sit upon the beam then cut/install the rafters (sawn, I-joist, whatever) on the ridge board as always. Beam takes the load off the ridge board, AHJ sees a compliant rafter/ridge connection...everyone's happy. Marc
medeek Posted December 14, 2015 Author Report Posted December 14, 2015 Version 1.2.0 - 12.13.2015 - Added ceiling joist option for Gable Rafter Roof. Note: In the image shown I have raised the ceiling joist 24", the default is zero, or resting on the top plate of the wall.
medeek Posted December 14, 2015 Author Report Posted December 14, 2015 Haven't installed any dropped ridge beams before but if I had to, the first thing to come to mind is to simply let a common ridge board sit upon the beam then cut/install the rafters (sawn, I-joist, whatever) on the ridge board as always. Beam takes the load off the ridge board, AHJ sees a compliant rafter/ridge connection...everyone's happy. Marc I've seen this done before and there are a few good pictures floating around out there on the internet.
medeek Posted December 14, 2015 Author Report Posted December 14, 2015 I've never framed a roof with I-joists myself. Every time I've seen it done, though, the I-joists rest in hangers on the side of the beam. If I had to make a beveled top strip, I'd do it just as I would for sawn rafters, with a table saw. I'd try to leave about 1/8" at the bottom ends of the strip because it's messy to taper down to nothing. I agree with the taper, it is hard to taper to a knife edge, probably the same reason the truss manufacturers use a standard 1/4" butt cut on trusses. I think I will update the bevel strip in the plugin to a 1/4" butt cut in order to keep things standardized.
medeek Posted December 17, 2015 Author Report Posted December 17, 2015 Version 1.2.1 - 12.16.2015 - Added gable end trusses (ladders) and ribbon boards to the floor truss type (Warren - System 42). - Sheathing option enabled under advanced floor options for floor trusses.
Steven Hockstein Posted December 18, 2015 Report Posted December 18, 2015 In actual practice, the primary roof is decked out before the secondary roof is placed upon it, correct? Marc Correct, that is why I have a sheathing offset (user input) that can be entered if you are selecting a face from the top chord of the truss instead of the sheathing. With the main roof sheathing: Don't forget that there has to be an access into both attic spaces. Assuming there is a fixed ceiling installed below, there has to be an opening between the attics or an access into each attic from the space below. I like to have an opening between the attics to allow for air circulation.
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