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Posted

Its hard to say what requires more effort, double the nails or clinching. I've thought about 6d, 7d or even 8d nails in single shear but to avoid splitting the spacing drives the nails apart and the gussets are going to get too large in my opinion. For now I'm going to start with nails only in double shear but may add in a single shear option later.

I've got the front end working now so you can look at the input options. It doesn't do anything yet (actually defaults to metal plates if you choose the wood option), but it gives an idea of the gusset options.

With wood gussets the web-chord joints are going to be much stiffer than with metal plates so I will probably set up the matrix analysis to consider all joints as rigid instead of pinned. I'm actually still thinking about that and talking to other engineers with regards to pinned, semi-rigid or rigid joints with this type of construction.

I would recommend extra nails because the contractor never gets to the note that requires cinching of the nails.

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Posted

I've uploaded a test L-Shaped structure with a hip roof:

https://3dwarehouse.sketchup.com/model. ... ba849765bb

I've created both hip roof primitives with the plugin, that was the easy part.

I then placed a valley rafter with its centerline (top) inline with both roof planes. I think I've got it right. What I am unsure of however, is the best way to terminate the framing at the intersection of the valley, lower ridge and flying hip. Once I have a handle on how a carpenter would actually construct that junction I think I can proceed to start work on a secondary roof module for both hip and gable rafter roofs.

The secondary roof module will allow one to add secondary roof geometry to a main roof and have it automatically adjust the rafters accordingly.

Posted

Basically, it would start with the larger primitive using 6 commons and the ridge but this particular ridge is too short to install 2 commons on the valley side of it so what I would do is this:

Support the upper ridge in position with a vertical ridge pole on each end. You'll need two guys up there for this feat.Install a common rafter attached to each plumb cut of the ridge.Install all four hips, all cut to full length. Nothing flies as long as both primitives share a wall.To that you can add your valley Now you can install the lower ridge to the hip on one end and with 3 commons on the other.

Everything else is straightforward.

Marc

Posted

One method of framing this roof configuration is to extend the lower ridge past the joint until it meets the next jack rafter, then the flying hip and valley are miter cut to meet the lower ridge.

I've created a version of the model above with this method of framing at the flying hip/valley/ridge joint:

https://3dwarehouse.sketchup.com/model. ... 9fd2b63705

What is the thinking on this method of framing this particular configuration?

My other concern is the way I have the valley rafter miter cut where it meets the fascia and the corner of the building wall (top plate). Is there a more practical way or better way of making those cuts?

Posted

I also like your method where there is no flying hip. I will create a version 3 of the hip roof using the method you've outlined for comparison. The questions is which method is stronger, more practical and perhaps either method is acceptable?

Posted

One method of framing this roof configuration is to extend the lower ridge past the joint until it meets the next jack rafter, then the flying hip and valley are miter cut to meet the lower ridge.

Very awkward to attach the lower ridge to a jack rafter which is attached to a flying hip. I've never even attempt it.

Marc

Posted

I also like your method where there is no flying hip. I will create a version 3 of the hip roof using the method you've outlined for comparison. The questions is which method is stronger, more practical and perhaps either method is acceptable?

The hip is bigger than the jack.

Marc

Posted

One method of framing this roof configuration is to extend the lower ridge past the joint until it meets the next jack rafter, then the flying hip and valley are miter cut to meet the lower ridge.

I've created a version of the model above with this method of framing at the flying hip/valley/ridge joint:

https://3dwarehouse.sketchup.com/model. ... 9fd2b63705

What is the thinking on this method of framing this particular configuration?

My other concern is the way I have the valley rafter miter cut where it meets the fascia and the corner of the building wall (top plate). Is there a more practical way or better way of making those cuts?

Installing jacks on a flying hip/valley is asking for trouble. If you get it wrong, you have to do it over.

Marc

Posted

This version of Hip Roof 4 has the flying hip extending as a full hip to the exterior wall and then the lower ridge framing into it with the valley rafter framed in last.

Posted

Why run one valley to the upper ridge? Two valleys - same length. Even the tails are the same.

I'd likely begin with the smaller primitive, same process as with a simple hip roof but with two hips and two valleys. Support the valley end of the ridge with a ridge pole then erect the larger primitive.

There's another, more common way but it wastes wood.

Marc

Posted

Why run one valley to the upper ridge? Two valleys - same length. Even the tails are the same.

I'd likely begin with the smaller primitive, same process as with a simple hip roof but with two hips and two valleys. Support the valley end of the ridge with a ridge pole then erect the larger primitive.

There's another, more common way but it wastes wood.

Marc

If you don't connect the valleys to either the upper ridge or hip then what is to support that end of the lower ridge?

Posted

The intersection of the supporting valley rafter, valley rafter and lower ridge I had framed incorrectly. The corrected method is shown below:

truss_su59_800.jpg

Also note that the segment of the supporting valley rafter between the upper ridge and lower ridge would need to be beveled or "backed" otherwise it clashes with the sheathing. I noticed this when I originally added the supporting valley rafter but confirmed my suspicion when perusing DeWalt's carpentry and framing handbook this morning. I probably should have pulled this book out before beginning this study but it only confirmed everything I had managed to discover myself once I started examining the model.

Posted

Why run one valley to the upper ridge? Two valleys - same length. Even the tails are the same.

I'd likely begin with the smaller primitive, same process as with a simple hip roof but with two hips and two valleys. Support the valley end of the ridge with a ridge pole then erect the larger primitive.

There's another, more common way but it wastes wood.

Marc

If you don't connect the valleys to either the upper ridge or hip then what is to support that end of the lower ridge?

Ridge pole.

Marc

Posted

Dutch Gable Rev. 3:

Doubled up gable common rafters but the dutch ridge/ledger is sandwiched between them. Found a paper by Larry Haun, Mar. 1995 "Framing a Dutch Roof" that was published in Fine Homebuilding magazine, that describes a very similar method of framing.

DUTCH_GABLE1.jpg

View model here:

https://3dwarehouse.sketchup.com/model. ... 0b6b0852a8

Disregard the common rafter sizes they are undersized but look at the method of sandwiching the dutch ridge/ledger between the last common rafters. I would probably also install some blocking between the double gable common rafters. I'm also not showing all of the ceiling joists and bird blocking etc...

If the roof gets large enough then one could go to a double ply dutch ridge, or even a deeper LVL member, assuming there is no internal support available from internal walls.

Posted

Version 1.2.8 - 02.02.2015

- Added Shed Rafter Roof with Ledger (all advanced options enabled).

- Added ceiling joist option for Shed Rafter Roofs.

- New submenu item and toolbar icon added for secondary (minor) roofs.

truss_su62_800.jpg

View model here:

https://3dwarehouse.sketchup.com/model. ... 7a2db95199

I used this option to create a monitor style roof line but it can also be used for porch roofs, carports etc... I still need to add a standard shed roof with and upper and lower birdsmouth cut.

Posted

Testing the real world application of the Medeek Truss Plugin. This model combines a double fink truss, raised heel fink truss, monopitch truss and shed roof with ledger. While creating the shed roof special attention to the birdsmouth cut was required to ensure that the fascia height of the rafters and trusses lined up. Also note the use of the raised heel type truss on the upper roof portion. Structural outlookers were specified for all gable overhangs.

5:12 pitch roofs with rafters and trusses 24" o/c. I did not apply a level cut to the rafter overhangs but that would probably be a given. Span of the double fink is 48 feet with 2x6 top and bottom chords.

truss_su64_800.jpg

View model here:

https://3dwarehouse.sketchup.com/model. ... aefca9b941

If anyone has some real world applications using the plugin that they are willing to share I would be very interested to see how it is being used and it would also give me some direction for further development and improvements.

Posted

Has anyone else checked out this guy's artwork? Very nice. He's not just about truss.

I also dabble a bit in the native art (Gitxsan), but I haven't done any significant work in a while just a few simple logos and some sketches. All of my free time has been spent on programming calculators and plugins the last three years.

My art is here: http://www.wilkersonart.com

Posted

Has anyone else checked out this guy's artwork? Very nice. He's not just about truss.

I also dabble a bit in the native art (Gitxsan), but I haven't done any significant work in a while just a few simple logos and some sketches. All of my free time has been spent on programming calculators and plugins the last three years.

My art is here: http://www.wilkersonart.com

Cool!

Marc

Posted

Version 1.2.9 - 02.12.2015

- Added Shed Rafter Roof (all advanced options enabled).

- Added ceiling joist option for Shed Rafter Roofs.

- Initial menu now defaults to last picked option of session for that sub-menu item.

A typical application might be a clerestory roof with a upper shed roof and lower shed roof with a ledger board:

truss_su66_800.jpg

View model here:

https://3dwarehouse.sketchup.com/model.html?id=u0b2dd5bc-605d-467c-a6bb-449bb54e76e6

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