medeek Posted February 15, 2016 Author Report Posted February 15, 2016 I am currently investigating the best method to construct the gable end wall and truss with a tail bearing truss. Show below are 3 different possible configurations: 1.) Structural Outlookers (Vertical) 2.) Non-Structural Outlookers (Horizontal) 3.) Structural Outlookers (Horizontal) This is just one possible method of framing the gable end wall into the gable truss with a 2x4 outlooker. Option 3 shown above is somewhat of a question, not sure how that heel joint would come together. View the model here to analyze the different configurations: https://3dwarehouse.sketchup.com/model.html?id=u75c42456-c8e5-4002-bc93-779860f8dc61
Marc Posted February 15, 2016 Report Posted February 15, 2016 I am currently investigating the best method to construct the gable end wall and truss with a tail bearing truss. Show below are 3 different possible configurations: 1.) Structural Outlookers (Vertical) 2.) Non-Structural Outlookers (Horizontal) 3.) Structural Outlookers (Horizontal) This is just one possible method of framing the gable end wall into the gable truss with a 2x4 outlooker. Option 3 shown above is somewhat of a question, not sure how that heel joint would come together. View the model here to analyze the different configurations: https://3dwarehouse.sketchup.com/model.html?id=u75c42456-c8e5-4002-bc93-779860f8dc61 #2 will sag. #1 provides a nail base for the soffit, #3 does not. I vote #1. Marc
medeek Posted February 15, 2016 Author Report Posted February 15, 2016 Alternatively one could balloon frame the wall at the gable ends and attach a ledger for the ceiling: View model here: https://3dwarehouse.sketchup.com/model. ... fd128b5913 In my opinion a partially sloping wall gets complicated to frame. From an engineering standpoint the balloon framed wall is also the strongest option.
medeek Posted February 16, 2016 Author Report Posted February 16, 2016 Version 1.3.1 - 02.15.2016 - Added Triple Fink and Quad Fink common truss types. - Structural outlookers (vert. & horz.) enabled under advanced roof options for Common (Triple & Quad Fink) truss types. Triple Fink @ 70' w/ 2x6 chords Quad Fink @ 80' w/ 2x6 chords View model here: https://3dwarehouse.sketchup.com/model. ... 89940c94b2
medeek Posted February 16, 2016 Author Report Posted February 16, 2016 I've been looking at a number of garage designs recently that employ an attic or storage truss. I'm finding that a lot of them tend to use raised heels to allow for more head room while having a lower roof pitch (ie. 6/12 - 8/12). I'm thinking about adding in raised heels for the attic truss type in the plugin. A quick mock up would look something like this: View model here: https://3dwarehouse.sketchup.com/model. ... 07185fa663 Ignore the unbalance in the panel lengths, in practice and in the plugin they will be properly balanced. What I do have a question on is the use of a top chord splice as shown in the above image so that the overhangs do not have to be as deep as the top chord in the non-triangulated region of the truss. I have never seen a splice used on a attic truss with a raised heel, I don't see why it can't be done but it is always nice to have a confirmation that someone else is doing this sort of thing in practice.
Jim Katen Posted February 16, 2016 Report Posted February 16, 2016 . . . What I do have a question on is the use of a top chord splice as shown in the above image so that the overhangs do not have to be as deep as the top chord in the non-triangulated region of the truss. I have never seen a splice used on a attic truss with a raised heel, I don't see why it can't be done but it is always nice to have a confirmation that someone else is doing this sort of thing in practice. I've never seen it done either. Seems like it would be fine.
medeek Posted February 23, 2016 Author Report Posted February 23, 2016 Version 1.3.2 - 02.23.2016 - Added Dualpitch truss type, configurations: (2/2-3/3). - Metric input enabled for dualpitch truss type. - Advanced options enabled for dualpitch truss type. View model here: https://3dwarehouse.sketchup.com/model. ... a8ffba4c36
medeek Posted March 3, 2016 Author Report Posted March 3, 2016 Version 1.3.4 - 03.02.2016 - Corrected a bug in the metric unit template module.
medeek Posted March 5, 2016 Author Report Posted March 5, 2016 Version 1.3.5 - 03.04.2016 - Added Bow Barrel truss type, configurations: (8/8). - Metric input enabled for bow barrel truss type. - Corrected a bug with the webs of the bowstring truss type. View model here: https://3dwarehouse.sketchup.com/model.html?id=u754b5fc3-c3ea-48cb-9f13-24c92ae39d97 Gable end option is also available (not shown in image above for clarity) for this truss type.
medeek Posted March 13, 2016 Author Report Posted March 13, 2016 Another study of hip roof framing where unequal pitches meet at the hip. The birdsmouth cut is 3.5" for all jack and common rafters. The hip rafter is dropped and off center so that it lines up with the roof planes. The hip roof combines a 12:12 pitch with a 6:12 pitch. View model here: https://3dwarehouse.sketchup.com/model. ... bc73878207
medeek Posted March 16, 2016 Author Report Posted March 16, 2016 Version 1.4.0 - 03.15.2016 - Added LP Solidstart? I-joists: 450, 530, 18, 36, 56. - Rim joist option enabled for LPI floor joists.
medeek Posted March 17, 2016 Author Report Posted March 17, 2016 Version 1.4.1 - 03.16.2016 - Added Soffit Cut within Advanced Options for Gable Roof and Gable Roof w/ GLB.
medeek Posted March 18, 2016 Author Report Posted March 18, 2016 I've been considering transition trusses and what it might take to add them into the plugin. Below is a quick study of this type of roof. I am curious to know if a common trusses is butted up next to a transition truss for sheathing purposes. Also notice the scissor transition, this situation is a little complicated, not exactly sure how to deal with it. View model here: https://3dwarehouse.sketchup.com/model. ... 2e3e134ba3
medeek Posted March 18, 2016 Author Report Posted March 18, 2016 This is a re-visit of the unequal pitch hip roof a few days back. Larry Belk, an experienced architect whose advice I highly regard, has suggested that an alternative way to handle this type of roof is to raise the top plate and thereby allow the overhang to remain constant around the roof: View model here: https://3dwarehouse.sketchup.com/model. ... 25d7ebd795 Compare with hip roof 7: and model: https://3dwarehouse.sketchup.com/model. ... bc73878207 A few things pop out at me here. First the raised top plate method allows the constant overhang with the continuous fascia, overall this is more aesthetically pleasing. Second the hip rafter is no longer at the corner but is jogged in some amount onto the higher wall. Third, the higher wall actually is protruding through the sheathing of the lower pitched roof in the model. Obviously the higher wall needs to be trimmed back some to deal with this. For the plugin I thing I will go with option 1 above initially but at some point it would be good to have a checkbox that allows one to choose either of these two options, the code is going to get ugly.
Marc Posted March 19, 2016 Report Posted March 19, 2016 It makes the location and size of the bird mouth difficult to calculate, not that I've tried it. I just measure and cut. Marc
medeek Posted March 19, 2016 Author Report Posted March 19, 2016 It's hard enough trying to figure these things out mathematically and then have SketchUp draw them. I have no idea how one could actually make some of these crazy double angle miter cuts. If it was up to me to build it I would probably have a huge pile of scrap lumber about 3 ft. deep around the entire perimeter of the house, when I was done.
medeek Posted March 19, 2016 Author Report Posted March 19, 2016 Version 1.4.2 - 03.19.2016 - Added energy/raised heels for attic trusses (1 variant: vertical w/ strut). - Addressed some minor usability issues with the attic truss menu and options. View model here: https://3dwarehouse.sketchup.com/model.html?id=u4f64fd8b-160f-49ce-815d-a66991527cdb I've had quite a few people asking for this update so stayed up most of the night and knocked it out. Note, that the raised heel option is currently limited to attic trusses with a span of 24 ft. or greater. The reason for this is the way my logic currently works with spliced top chords. If this becomes an issue I will spend some more time on it to encompass attic trusses with a lesser span. I still do not have the gable truss, metric input or structural outlookers for this truss type, yet more items for the "todo" list.
medeek Posted March 20, 2016 Author Report Posted March 20, 2016 Thinking about dormers today and attic trusses: View model here: https://3dwarehouse.sketchup.com/model. ... 5691b1c678 2-ply girder trusses on each side of the dormer with ladder framing between. I haven't bothered to show all of the main floor framing geometry (doors, windows, stairs etc...) My question is what would be the best route for the infill framing above the dormers. 1.) Ladder frame perpendicular to trusses. 2.) Install a ridgeboard hangered between the girder trusses and a lower header and install rafters parallel to the trusses? Note that the manual creation of the dormers took about an hour whereas the attic truss main roof and dormer roof were created with the plugin and only took about 5-10 minutes. A dormer routine would be useful.
Jim Katen Posted March 20, 2016 Report Posted March 20, 2016 Thinking about dormers today and attic trusses: View model here: https://3dwarehouse.sketchup.com/model. ... 5691b1c678 2-ply girder trusses on each side of the dormer with ladder framing between. I haven't bothered to show all of the main floor framing geometry (doors, windows, stairs etc...) My question is what would be the best route for the infill framing above the dormers. 1.) Ladder frame perpendicular to trusses. 2.) Install a ridgeboard hangered between the girder trusses and a lower header and install rafters parallel to the trusses? Note that the manual creation of the dormers took about an hour whereas the attic truss main roof and dormer roof were created with the plugin and only took about 5-10 minutes. A dormer routine would be useful. When I designed and built my office, I did something similar except that the dormers were stick framed and vaulted on the inside. I used a ridge board between two sets of girder trusses. It gave me the freedom to vault the interior.
Marc Posted March 20, 2016 Report Posted March 20, 2016 So, a girder truss is just two or more trusses joined together side by side to form a single, stronger truss? Marc
medeek Posted March 20, 2016 Author Report Posted March 20, 2016 So, a girder truss is just two or more trusses joined together side by side to form a single, stronger truss? Marc Correct, you can even join more than two together. If the dormer were to get wider than a triple ply girder would be more appropriate. In typical girder design you will also see the Howe truss used since the panel length is shorter along the bottom chord than a fink truss. The bottom chord is also increase to a 2x6 or 2x8 member to allow for truss/joist hangers.
medeek Posted March 20, 2016 Author Report Posted March 20, 2016 A basic algorithm to convert a common gable truss into a transition truss should not be to much problem. However, to make it handle all cases would become difficult if you include raised energy heels, drop top chords and scissor trusses in the mix. Consider the two examples below:
medeek Posted March 21, 2016 Author Report Posted March 21, 2016 Version 1.4.3 - 03.20.2016 - Added Scissor truss type, configuration: (6/6). - Added energy/raised heels for scissor trusses (2 variants: wedge and vertical w/ strut). - Addressed some minor usability issues with the scissor truss menu and options. View model here: https://3dwarehouse.sketchup.com/model. ... 3de30e3696
medeek Posted March 21, 2016 Author Report Posted March 21, 2016 Polynesian 4/4 truss is working: However, I haven't released this latest update yet, I still need to enable gable end trusses and advanced options for this truss type before it is ready for prime time. The inputs are similar to all other truss types except you have two top chord pitches and a pitch break length measured from the left butt cut of the truss.
medeek Posted March 22, 2016 Author Report Posted March 22, 2016 Version 1.4.4 - 03.21.2016 - Added Polynesian truss type, configurations: (4/4). - Metric input enabled for polynesian truss type. - Added gable end trusses for polynesian truss type. I'm not sure where this type of truss is commonly used but whenever I see one I think of a bus stop or train station: Advanced options are not yet enabled for this truss type yet, so sheathing, fascia, rake will have to come later.
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