Truss Designer 2015 Updates

[medeek]

Using a typical Barrel Vault 8/7+4 or 8/7+2 configuration I come up with the following triangulations. I'm sure there are other methods of configuring these webs but for the purposes of the plugin I think these solutions will suffice for now:

High Resolution PDF copy here:

http://design.medeek.com/resources/trus ... _REVA2.pdf

Based on this matrix I've been able to come up with a simple algorithm for the triangulation of this truss type. I'll admit the barrel vault truss is one handsome devil.

[Marc]

It's interesting I don't see many folks using these cool truss designs.

Marc

[medeek]

A 9:12 barrel vault truss with a 16' wide barrel:

PDF:

http://design.medeek.com/resources/trus ... _REVA3.pdf

[medeek]

You're right you probably won't see many of these on your typical residential job. Mostly high end residential and commercial.

[medeek]

Another look at the cambered truss:

[medeek]

Version 1.4.6 - 03.26.2016

- Added Cambered truss type, configurations: (6/X).

- Metric input enabled for cambered truss type.

- Added gable end trusses for cambered truss type.

Six variants of the (6/X) configuration dependent on the ratio of the camber width to span. Notice that in all cases the top chord has six panels, the bottom chord varies from 4, 5 and 6 panels.

View model here:

https://3dwarehouse.sketchup.com/model. ... 15cf876fdf

[medeek]

Version 1.4.7 - 03.28.2016

- Added Cathedral truss type, configurations: (4/X, 6/X).

- Metric input enabled for cathedral truss type.

- Added gable end trusses for cathedral truss type.

Note, that not all configurations have webs enabled however the top chords, bottom chords, gable end trusses and all advanced options are enabled.

[medeek]

To further clarify the framing details with regards to attic trusses and structural outlookers I've created a sample model with a proposed dropped top chord gable end attic truss:

Please download and review the model here:

https://3dwarehouse.sketchup.com/model. ... 8b1cccd8bc

I've also included the infill wall framing to help put everything into reference (light green).

Is this the appropriate way to frame an attic truss (gable end) with structural outlookers?

[Marc]

The span between the last truss (not the gable truss) and the barge rafter is too great. As we all know, structural roof panels are rated only along the longer dimension and won't span that far.

Maybe install purlins right along the top of the gable truss between the outlookers to cut the span in half. Even then, some AHJ's would be concerned about its structural integrity under condition of high winds. You'd perhaps have to engineer that in.

Marc

[medeek]

There will be solid block installed above the gable end truss between the outlookers which will solve the span issue you have described, I probably should have drawn those in as well.

[medeek]

Six possible end details for a flat truss (Pratt 4 panels), there are probably others but these seem to be the most common:

1.) Mansard w/ Parapet

2.) Parapet

3.) Mansard

4.) Overhang

5.) Cantilever

6.) None

Both Mansard configurations can also have an optional overhang as shown. The Parapet configuration should allow for customizing the thickness of the parapet wall.

View model here:

https://3dwarehouse.sketchup.com/model. ... d2044182ad

This truss type with its many end configurations would work well with an HTML UI, that is the direction I will be going with future user inputs and interfaces since the ability to customize is unlimited.

With the flat trusses I will initially offer both Howe and Pratt with the ability to utilize a low slope or zero slope.

[medeek]

Version 1.4.8 - 04.01.2016

- Added Mod Fan common truss type.

- Structural outlookers (vert. & horz.) enabled under advanced roof options for Common (Mod Fan) truss type.

View model here:

https://3dwarehouse.sketchup.com/model. ... 93296cca33

With the addition of the Mod Fan (Triple Fan) the line up of common trusses is complete. I still need to add in raised heels and structural outlookers for some of the configurations.

Theoretically I could add in additional configurations of the Fink and Howe truss types for extremely large roofs but the largest I've ever seen is a raised heel Quad Fink (10/9). Large spans beyond 70'-80' are probably not practical as far as a single span common truss roof. At that point you pretty much go with large flat roofs with interior columns and girders and all steel construction (think Walmart or Cosco).

[Jim Katen]

. . . With the addition of the Mod Fan (Triple Fan) the line up of common trusses is complete. . . .

Surely not.

When I was in school, we had to design a truss in the shape of the Sinclair Dinosaur using the fewest possible members. I could really have used a program like yours then. (Except there was no internet, no personal computers, and we were required to use slide rules because calculators were too expensive. . . )

[medeek]

Version 1.4.9 - 04.04.2016

- Added Tray truss type, configurations: (AUTO).

- Metric input enabled for tray truss type.

- Added gable end trusses for tray truss type.

[medeek]

. . . With the addition of the Mod Fan (Triple Fan) the line up of common trusses is complete. . . .

Surely not.

When I was in school, we had to design a truss in the shape of the Sinclair Dinosaur using the fewest possible members. I could really have used a program like yours then. (Except there was no internet, no personal computers, and we were required to use slide rules because calculators were too expensive. . . )

Actually you do bring up a very serious point with this comment. It would be very useful if I could develop and interface which allows for any custom truss simply by stretching and pulling the center lines of the members, and the insertion of any member by merely drawing a single line. The program then auto draws the members with the appropriate scarf cuts etc... I will need to give this some further thought.

[medeek]

Some tray truss configurations generated by the plugin, note the auto configuring of the webs depending on span lengths, this should cover most residential trusses up to about 40' in total span:

[Jim Katen]

. . . With the addition of the Mod Fan (Triple Fan) the line up of common trusses is complete. . . .

Surely not.

When I was in school, we had to design a truss in the shape of the Sinclair Dinosaur using the fewest possible members. I could really have used a program like yours then. (Except there was no internet, no personal computers, and we were required to use slide rules because calculators were too expensive. . . )

Actually you do bring up a very serious point with this comment. It would be very useful if I could develop and interface which allows for any custom truss simply by stretching and pulling the center lines of the members, and the insertion of any member by merely drawing a single line. The program then auto draws the members with the appropriate scarf cuts etc... I will need to give this some further thought.

That would be an awesome feature.

[medeek]

Version 1.5.0 - 04.11.2016

- Added Mono Scissor truss type, configurations: (2/2, 3/3).

- Metric input enabled for mono scissor truss type.

- Added gable end trusses for mono scissor truss type.

- Structural outlookers (vert. & horz.) enabled under advanced roof options for Mono Scissor (2/2, 3/3) truss types.

When the raised heel option is selected the pitch of the bottom chord may equal the top chord creating a half vaulted parallel chord truss.

View model here:

https://3dwarehouse.sketchup.com/model. ... c21ec12a3d

[medeek]

Version 1.5.1 - 04.16.2016

- Added Dutch Gable Rafter Roof (all advanced options enabled).

- Added wireframe (temporary) graphics to the roof positioning tool for rafter roofs.

View model here:

https://3dwarehouse.sketchup.com/model. ... 4bc4c1f1e7

I still need to setup ceiling joists for hip and dutch gable roofs.

[medeek]

A nested dutch gable roof created with the plugin. The roof is initially generated by creating three dutch gable primitives and then deleting and trimming certain elements. The most time consuming is the creation of the two valley rafters. I think it might be helpful to have some sort of valley rafter tool if I can figure out a good way of doing that.

View model here:

https://3dwarehouse.sketchup.com/model. ... 208c9d93ef

[medeek]

Per user request:

Version 1.5.2 - 04.18.2016

- Added energy/raised heels for small span attic trusses (less than 24 ft.), 1 variant: vertical w/ strut.

- Added some additional logic to improve the triangulation of the upper attic of attic trusses.

When I get some more time I will add in slider and wedge raised heel options for the attic truss type but at that moment it is low priority since most users seem to favor a fairly tall raised heel when utilizing it with attic trusses.

[medeek]

Version 1.5.3 - 04.20.2016

- Added Mono Cathedral truss type, configurations: (2/2, 4/4).

- Metric input enabled for mono cathedral truss type.

- Added gable end trusses for mono cathedral truss type.

- Structural outlookers (vert. & horz.) enabled under advanced roof options for Mono Cathedral (2/2, 4/4) truss types.

- Added Mono Scissor truss type, configuration: (4/4).

View model here:

https://3dwarehouse.sketchup.com/model. ... 05eb1288f9

I manually modeled this truss type about two months ago and I have been meaning to add it in, finally got it done tonight.

Manually created model here:

https://3dwarehouse.sketchup.com/model. ... bfa780ee7f

[medeek]

Version 1.5.4 - 04.21.2016

- Added a graphical user interface (GUI) for the selection of the truss type in the "Draw Roof Truss" sub-menu.

- GUI can be toggled with previous drop down menu within global settings.

As you can see there is only one global setting at the moment but now that I have the interface and back end properly setup it won't take much to add in a number of other global values. At some point I will probably have enough parameters that I will need to enable some sort of tabbed html front end for the global setting menu.

With html web dialog boxes I am not sure how well they work on a Mac, the whole sync vs. async issue is a real problem for web dialogs and Macs. I only test on a PC so I can't guarantee 100% compatibility on a Mac. So far I haven't had too many complaints.

[medeek]

Here is a preview of the Geometry Input (GUI) menu for the upcoming gambrel attic truss.

Notice the preview pane which gives a basic profile of the truss and attic space. I still need to add some dimensions and some other symbols (pitch, bearing walls, etc...) to the preview graphics but it is mostly there and functioning quite admirably.

The GUI is html with javascript and SVG (scalable vector graphics) for the image. The nice thing is that changing any of the inputs will instantly update the dimensions and preview image allowing one to fine tune the truss geometry before proceeding further. For gambrel roofs this ability to adjust the proportions of the roof relative to each other is very important in my opinion. See my previous gambrel study here:

http://design.medeek.com/resources/trus ... study.html

[medeek]

A reset button would be useful to return the GUI to the default values. There is still a lot of work to be done with the gambrel attic truss type:

- Advanced Options

- Gable Trusses

- Default or Reset Button

- Metric Input

View model here:

https://3dwarehouse.sketchup.com/model. ... a62628ae95