Truss Plugin/Extension


Knocked out the update to the cladding and ridge cap last night. I’ve released 2.1.4d so that everyone can test out the advanced options.

The following advanced options (gambrel attic) must be turned off currently:

  • gutters
  • gypsum
  • heel blocking




Have not implemented a closed soffit yet.


Seems like Truss is going far beyond what one would normally expect from an app with the name “Truss”, Not complaining…just acknowledging.


Initially I started with just the trusses, however it only made sense to start adding other pieces of the puzzle.

Technically the plugin should probably be called a “roof and floor” plugin (ie. Medeek Roof and Floor Plugin) however I like trusses so I’ll stick with the original name for now.

As time goes on I would also like to add in some reporting elements so one can generate a bill of materials and then some cost estimating features.

That is the beauty of plugins and the ability to program, its really open ended, you can take it as far as you want to.


All of the remaining advanced options (gutters, gypsum, heelblocks, outlookers) are now in place for the Gambrel Attic Truss, at least as many as I am going to attempt right now. I still need to figure out structural outlookers for this truss type so that permutation of the outlooker option will be disabled for now.

Also note that for this truss type the heelblocking is only allowed to be vertically oriented, however I am willing to entertain angled heel blocks if someone can provide some form of documentation showing how they would be installed in a non-vertical orientation.

I have a bit more tidying up to do with the new Html menu for this truss type and then I should be able to roll it out tomorrow or this weekend.

View model here:


This morning as I was thinking about what else needs to be done I realized that it wouldn’t be too hard to add in the gable wall framing, especially for the gambrel attic since it is always regular rectangular shape.

To add in windows or doors one would simply right click on the wall group and an HTML menu will pop up that will allow for the creation of multiple windows and doors with an interactive SVG/JavaScript interface.

This menu will also allow for editing and deleting previously added windows or doors.

Once I have this module coded it will drop right into the wall plugin, no point in creating the wheel twice.

A option within this menu will allow for inserting actual doors or windows into the openings, this is going to get complicated but its going to be fun.

My only uncertainty at the moment is how to establish and store the information which tells me which side of the wall is facing the exterior. I will need to know this in order to repeatedly cut and redraw studs and also for proper window and door placement and location.


Version 2.1.5 - 02.16.2018

  • Added floor sheathing and attic gypsum for gambrel attic trusses.
  • Added roof cladding, sheathing and ridge cap for gambrel attic trusses.
  • Created a separate HTML menu for advanced options of gambrel attic trusses.
  • Enabled gable end trusses for gambrel attic trusses.
  • Enabled hurricane ties for gambrel attic trusses.


Well there would be your possible need for rotated bird blocks that you requested previously.




It looks as though the birdblocks in the images are beveled on top. If that’s the case I assumed it was to give support to the sheathing of the steeper plane above the pitch break when the lower plane of the eave would actually need it more than the previous. In colder climates snow is going to shed from this roof and cause some possible deflection at the pitchbreak . Ice is going to tend to form more readily at the upper pitchbreak becasue of the heat loss caused by the reduced insulative values in the area which is a common concern with attic truss construction. I’m sure you know all this.
My thought was perhaps the bird block could be rotated perpendicular to the lower eave pitch to give support where it’s needed and eliminate the bevel which most likely would never happen irl.


You do make some very valid points, especially with the bevel at the top of these heel blocks. The typical pitch will be too steep which will make the bevel impractical IMHO, and would probably not be done in practice.

With larger heel blocks my experience has been that most contractors go with a vertical block not saying that an angled block can’t be used.

The purpose of the heel blocks is not really to provide support for the roof at this point but to prevent truss roll over and and also to provide a continuous load path from the roof diaphragm (sheathing) into the wall below.

I may just eliminate the top bevel on the vertical heelblocks.

I’ll look at adding the angled heel block option back in as well.


Well if you eliminate the bevel you may as well eliminate the holes for air flow becasue most framers would use the nearest size material to come close to filling the space while still leaving an inch or two above the birdblock for air flow which can then be screened off for open soffits. It’s a trade off in labor I realize but in the usual haste to dry in a roof structure, it usually proves more popular.
The hammering of ice dropping from the upper pitch break would indeed be something to address on this style of roof and would have to have some ill affects on the substrates, water proofing and fasteners whether the roof covering is asphalt or metal.
Sorry to divert your thread but you had asked previously for reasons to rotate the blocks.
Nice extension.


The crow’s beak for the gambrel attic roof has been on my todo list for about a year and a half now. Grateful that I was able to somehow find the time to put this one together tonight.

The projection of the crows beak and the length along the rake can both be set by the user.

I will roll this out tomorrow as 2.1.5b once I’ve finished testing it.

View model here:


I’ve added in thumbnails to the sheathing tab of the global settings so the user can preview the wall and roof cladding materials:


Version 2.1.5b - 02/18/2018

  • Added a crow’s beak option for gambrel attic trusses.
  • Added thumbnails for wall and roof materials in the sheathing tab of the global settings.


This barn is very similar to the one we had at our first farm in Terrace B.C. Canada:

Foundation was created with the foundation plugin.

View model here:


The thing I find very interesting with the gambrel roof is the two pitches, whereas with your typical gable roof you only have one pitch and each side of the roof is simply the hypotenuse of half the span and the height of the peak.

With a gambrel roof you have the two legs of the roof and the two pitches and an infinite number of possible combinations and hence a large variety in the shape of the gambrel roof.

Ultimately this led me to create the HTML/SVG preview panel so that the user can play with the various parameters until the desired gambrel shape is achieved. I believe this is where the real power in this plugin in manifest, in situations where an architectural element can be realized by incrementally adjusting parameters within the user interface.

A common truss is much more simpler than the gambrel but a similar preview screen would be helpful in my opinion.


As I was creating the various test models for the gambrel attic truss yesterday I realized that the color I had initially set for the gypsum material was slightly off white, which for my particular case was just fine. However, after giving it second thought I realized that the gypsum color (material) should also be configurable so I added in one additional setting into the sheathing tab.

Then my 13 year old son (Jared) suggested that I implement some sort of color picker since most people don’t equate a hexadecimal RGB value with any particular color (ie. #FF2C9F). I found a simple javascript based color picker and modified it to fit my needs, hopefully this is somewhat helpful.

Under the materials tab I will probably implement similar options where one can modify the color of the lumber and the pressure treated lumber. For now I will probably keep the plywood and the OSB material/texture as default. If someone really wants to modify those it is simply a matter of replacing the .jpg image with their own custom image within the plugin folder.

Since javascript tends to be a bit browser dependent I am curious how well this works on MacOS with the background browser running as Safari, please let me know if there are any issues.

The color boxes at the bottom of the color picker provide some shades of grey as well as the default Medeek colors for: lumber, pressure treated lumber, gypsum.

This minor update is rolled into sub-revision 2.1.5c.


I took a step back today and pulled my head out of the sand, so to speak.

The truss plugin does some pretty cool stuff and its fairly detailed where I’ve fleshed out certain truss and roof types. However, it is missing one major feature or has a major flaw depending on how you want to word it.

Currently the plugin is “fire and forget”, with no ability to edit an existing roof or floor assembly. This needs to change.

I have a mental picture of how I want to handle this but there may be some flaws with my thinking.

I briefly discussed this with a few others at this thread:

My idea is to right click on a roof or floor assembly, then click “Edit Assembly” at which point the plugin will bring up a very concise list of parameters for the assembly. Changing any one of the various parameters or settings will essentially redraw the entire (roof, truss, floor, dormer) assembly. The list will remain open after each edit and only be closed if the user decides to close it.

My original idea was to have the edit process walk the user back through each UI menu but this is too time consuming and probably unnecessary.

Any manual edits made to the assembly will of course be lost but this is the price of having a fully editable assembly.

I think I can implement this fairly easily, the various modules are all utilized the same as when I originally created the assembly, the only difference being the user interface.