Development and Updates for the Medeek Truss Plugin

[Medeek]

I need to be able to select a face from a truss (truss top chord) even when the entire truss set is nested within a group -> component -> group. I'm going to assume this is possible, even though I don't know how to do this yet. If I can do this I can see a path to creating the valley set code which will allow one to insert a valley set behind a given truss set and have it frame over the main roof, conforming to the main pitch of the roof. At this point I'm only going to make it work if the two ridge lines are perpendicular. If they are different than 90 degrees the calculations are going to be a nightmare, I'll put that one on hold for a later time when I feel particularly ambitious.

[Medeek]

Version 1.1.0 - 11.10.2015
Gable end trusses enabled for the Fink truss type and all raised heel variants.

I may need to adjust the vertical studs slightly for the raised heel with slider.  I haven't yet determined the best way to frame that situation out.

[Medeek]

On a slightly different note I'm thinking about creating a plugin for wall framing and other misc. framing related items for residential construction:

- Walls
- Floors
- Stairs
- Dormers
- Foundations
- Posts and Beams
- Square and Round Footings

Any great ideas on names.  Its going to be something like Medeek Framer or Medeek Construction but I just don't want to make it too narrow in scope since I will probably wrap a number of things into it.

I like the housebuilder extension but I think a lot more can be done based on this initial concept.

Items I would like to see are more flexibility in defining openings, double trimmers, double king studs, double window sill plates. 

I would also like to have the ability to create portal frames per the IRC standard.  As well as classify certain wall segments as shearwalls and automatically insert the holdown components (Simpson HDU series) into the wall.

For structural engineers I've got some ideas for a plugin called Medeek Structure which will do lateral load analysis for wind and seismic similar to the Woodworks Shearwall software that I currently use on my local engineering projects.

[Medeek]

I haven't even looked at traditional roof framing, its been all trusses and some floor joists until now.


Hip roof framing is very complicated especially with intersecting roof lines:





and

[Medeek]

Actually let me rephrase that, any roof can get very complicated with intersecting roof lines whether it is framed out with trusses or more traditional rafters and beams.

If I incorporate traditional framing I would like for the user to be able to indicate the perimeter of the ext. walls and for the logic to be smart enough to handle any possible configuration.  Consider the custom home with guest house below:



Just to determine the proper placement of the ridge and valley lines requires some serious algorithms.  The technique I used to do it manually simply involves drawing isolines moving a fixed increment in from the ext. wall line.  These are really no different than contour lines on a topographic map.  The vertexes created by the intersection of these lines indicate the location of hip rafter, flying hip rafters and valley rafters.  When the isolines merge into one line then you have a ridge board.

This process is known as the straight line skeleton:

https://en.wikipedia.org/wiki/Straight_skeleton

[Medeek]

An interesting implementation of a straight line skeleton algorithm is at this link:

[Medeek]

Version 1.1.1 - 11.14.2015
- Gable end trusses enabled for all monopitch truss types.
- Added energy/raised heels for monopitch trusses (3 variants: wedge, slider and vertical w/ strut).


Currently there are only two versions of the monopitch truss available (2/2 and 3/3). 

The truss set below shows a monopitch truss set with gable ends and a 36" raised heel.

[Medeek]

I've also added advanced options for monopitch trusses (sheathing, rake and fascia).

[Medeek]

Version 1.1.2 - 11.16.2015
Metric input enabled for monopitch truss types.

[Medeek]

Given the slopes of the dual pitch truss and the span calculate the distance between the left bearing and the peak:



However, you might notice that we are assuming the buttcut and top chord depth is equivalent for both sides.  If the slopes are different then this will mean that the heel heights will be different.  Should the heel heights be the same?

[Medeek]

Outlookers enabled under advanced roof options for Common, Scissor and Attic truss types.




Not really sure what is the best treatment of the outlookers at the peak of the roof and consequently what is best way to space them.  Measure them from the peak or the eave/fascia?

One thing worth noting here is that structural outlookers are also enabled but I have not yet coded in the dropped top chord gable end trusses that would match structural outlookers, something for another day. Due to the option of vertically or horizontally oriented outlookers the configuration of a dropped top chord gable end truss can take two configurations. For attic trusses this gets even more complicated at the gable end, hence I haven't even attempted the gable end truss option for attic truss types yet.

The hot items on the todo list right now are:

- Tail Bearing Trusses
- Gambrel Attic Trusses
- Dual Pitch Trusses
- Rafter Roof (Gable and Hip)
- Valley Truss Set
- Hip Truss Sets

If you feel like something should take precedence over these items please advise.

[Medeek]

Version 1.1.3 - 11.21.2015
Outlookers enabled under advanced roof options for Common, Scissor and Attic truss types.
Gable end trusses enabled for (2/2, 4/4) scissor truss types.

[Medeek]

Outlookers get a little complicated depending on whether they are structural or not.  Typically around here we see them at 24" on center and they are usually structural.  The top chord of the truss is dropped either 1.5" or 3.5" depending on if they are oriented horizontally or vertically.  With structural lookouts the first lookout from the eave is usually non-structural since the dropped top chord truss will have a special slider attached to top chord to achieve the overhang. See image below:



Usually the sheeting goes on starting at the bottom so based on that the lookouts would be measured from the bottom edge of the sheeting so that they line up with the seams every 48".

I've seen a single vertical placed the ridge when the outlookers are vertical however what is common practice when the outlookers are horizontal?

Notice the different configuration of the top chord when the drop is only 1.5" (oriented flat).



If the overhang is zero then this slider or splice goes away.

[Medeek]

A dropped top chord with flat orientation might look something like this:





Without an overhang the gable end truss becomes:





Note that the outlookers would probably be spaced from the bottom at 24" on center.

[Medeek]

Vertical structural outlookers with 12" overhang and 16" gable overhang: