Truss Design

[mbshop]

My bil is a civil engineer. He works independently and checks architects drawings. He does school and federal designs. He worked a looong time for a truss co. I will ask him what he uses.

 

[Medeek]

Looking through some old plans I've managed to dig up I came upon a couple of designs by another engineering firm.

Typically when I've dealt with truss designs I always seen a scarf cut on the bottom chord with the top chord remaining un-notched. In this other example the bottom chord is kept intact and the top chord is scarf cut or notched, while still allowing a continuous section to extend for the overhang with a depth equal to at least 1/2 the top chord depth. I think the picture below explains this far better than I can with words:

For MPC trusses I am used to seeing a 1/4" **** cut, however for timber trusses what is more appropriate?

Which method above would go with (arch. and structural reasons)?

View model here:

https://3dwarehouse.sketchup.com/model.html?id=6d3633a4-3b5c-4b9f-9780-23be5230c66d

 

[mbshop]

sooo, i talked to my bil. he said there are already a lot of co out there with the capability of designing trusses and other stuff. even a truss builder will design a truss for you based on your measurements. but there are programs out there that engineers and architects use. one of several he uses is called enercalc. its a paid program. so anyway, hope that helps.

 

[prostreetamx]

Currently building a 38x30' garage with the trusses going the 38' way. I had to pay 10 percent of the final bill for the trusses just for the engineering. Even though I had already paid $2000 for engineered plans for the garage that also included basic truss design and layout but not engineering. After the trusses were speced out and I had wet stamped drawings for them, I had to resubmit them back to the original engineer for his additional stamp before the building department would even look at my plans. I can see where having a program yourself might give you more insight to the building process, there still will be no long term benefit once you hit the building department. When I predrew my original specs and plans to submit to the architect, I knew they were just guidelines of my desires and needs and I gave them the option of changing stuff as needed to fit the local building codes.I have a whole new understanding about sheer panel I will never need again. I had planned all along to use an engineered roof truss and drew them in based on the knowledge that the final design could vary, it didn't change the design at all.

 

[Medeek]

Version 1.7.4 - 12.20.2016
- Enabled metal plate connectors for gambrel attic trusses.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=5297dc32-fe7a-4bdc-bab2-ccadba5e5147

 

[Medeek]

Currently building a 38x30' garage with the trusses going the 38' way. I had to pay 10 percent of the final bill for the trusses just for the engineering. Even though I had already paid $2000 for engineered plans for the garage that also included basic truss design and layout but not engineering. After the trusses were speced out and I had wet stamped drawings for them, I had to resubmit them back to the original engineer for his additional stamp before the building department would even look at my plans. I can see where having a program yourself might give you more insight to the building process, there still will be no long term benefit once you hit the building department. When I predrew my original specs and plans to submit to the architect, I knew they were just guidelines of my desires and needs and I gave them the option of changing stuff as needed to fit the local building codes.I have a whole new understanding about sheer panel I will never need again. I had planned all along to use an engineered roof truss and drew them in based on the knowledge that the final design could vary, it didn't change the design at all.

If you don't mind I wouldn't mind looking at your truss set, mostly for educational reasons but mostly my own curiosity.

 

[Medeek]

Version 1.7.5 - 12.24.2016
- Enabled metal plate connectors for valley truss sets.
- Enabled materials and custom layers for valley truss sets.

Merry Christmas to all.

 

[Medeek]

Version 1.7.7 - 12.31.2016
- Enabled materials and custom layers for gable, hip, shed, TJI and dutch gable rafter roofs.

 

[Medeek]

Version 1.7.8 - 01.02.2017
- Enabled materials and custom layers for gable dormers.
- Added advanced options for gable dormers, enabled exterior wall sheathing option.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=5b255dad-4823-450d-a7d9-153d983e73a5

 

[Medeek]

This is an example of custom layers and materials implemented in the Medeek Truss Plugin and Medeek Foundation Plugin and used in one model:

View model here:

https://3dwarehouse.sketchup.com/model.html?id=5ff9d1dc-7384-4c7f-bc8a-915c2cd3fc6c

Turn off the sheathing layers first to reveal all of the structural framing etc...

Regular walls were created with the Housebuilder plugin.

The trim tool in the Truss Plugin was used quite successfully to manually trim back the dormer roof framing and sheathing.

 

[Medeek]

Raised/Energy heels add another level of complexity to the equation. Below you can see that various heights of a raised heel on a simple King Post truss requires different configurations and hence separate plating routines:

This also affects the gable trusses as well, below is a fink truss with its gable counterpart:

View models here:

https://3dwarehouse.sketchup.com/model.html?id=91d8d78a-8e6c-4dab-9839-4d689c84c297
https://3dwarehouse.sketchup.com/model.html?id=89739563-049f-4277-bfca-75663724967e

I'm still house cleaning. I've now got the King Post and Fink truss fully cleaned up with connector plates enabled for all possible configurations (raised heel, non-raised heel, structural, non-structural). I've only got 10 more common truss types to work through, see list below:

Queen Post
Howe
Fan
Mod Queen
Double Fink
Double Howe
Mod Fan
Triple Fink
Triple Howe
Quad Fink

 

[Medeek]

Version 1.7.9 - 01.15.2017
- Enabled metal plate connectors, materials and custom layers for the common king post and howe trusses.
- Added energy/raised heels for howe truss (3 variants: wedge, slider and vertical w/ strut).
- Metal plate connectors now enabled for king post, fink and howe raised heel/energy trusses.

 

[Medeek]

I'm still investigating "real world" applications of the plugin to determine where the weakness and deficiencies are. Here is an example combining a dutch gable rafter roof with some raised heel trusses. Now that the raised heel feature is fully active for many of the common trusses it is actually quite easy to measure and then match the heel height of the rafters.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=461e63b6-4965-4697-b864-a9fbe464d53a

I am interested in how others are actually using the plugin and where it is falling down for you, please feel free to send me models or post on the forum with your "real world" design issues with regards to the plugin. This will help drive future development and prioritize the more important items on the todo list.

 

[Medeek]

Another item I have been putting off is the heel blocking. I'm planning on offering two variants (vertical and angled), with the option to draw in the ventilation holes (typically 2" in diameter in my region, with 3 holes per 24" o/c spacing) if desired:

Obviously this is not a hot item since no one has bugged me about it but I have not forgotten it, just put it aside up until now.

With raised heels this may become a bit more complicated requiring more options, (ie. a V-cut instead of the typical bird holes). More input from builders would be useful in this regard.

 

[Medeek]

I've got the plywood material working quite well in the plugin, and the ability to toggle between it and OSB in the global settings. I have a few more other features and edits and then maybe I will role a revision tomorrow or Sunday.

I actually like the plywood look much better than the OSB.

 

[Medeek]

OSB or Plywood will now be an option for the floor sheathing:

The new sheathing tab in the global settings:

As time goes on I will probably add in more options for wall cladding and interior wall cladding (ie. gypsum) as well as the ceiling logic I discussed in a previous post.

I'm now working on the gable end wall sheathing option and the roof cladding option.

There are also two new options in the "General" tab which allow one to toggle the default setting for gable end trusses and advanced options (roof, floor etc...).

 

[Medeek]

Version 1.8.0- 01.22.2017
- Enabled roof cladding for common trusses.
- Added nine "IKO Cambridge" architectural shingle colors into the roof cladding material library.
- Added "plywood" material for roof and floor sheathing.
- Added a "Sheathing" tab into the global settings.
- Added entries in the "General" tab of the global settings to toggle default settings for gable end trusses and advanced options.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=408cd4f0-26b0-416f-bcd0-c14e5565c97a

Initially I was just going to texture the exterior face of the sheathing for the roof cladding but then I realized that there may be cases where there is roof cladding but not sheathing or vice versa. In the end I went with a separate layer, material and extrusion for the roof cladding, this allows one to get more granular with the structure and in my mind closer to reality.

 

[Medeek]

Trying to find a good wood shake or shingle roof texture, this one is pretty good except for a bit of banding:

Slipped in a wood shingle roof texture and a few metal ones in to Version 1.8.0.

 

[Medeek]

Thinking about sheathing and cladding advanced option for the valley truss set. Typically the valley truss set is placed on top of the main roof sheathing:

View model here:

https://3dwarehouse.sketchup.com/model.html?id=c8b9995c-1649-4f2a-a769-9fdb685d0913

If I create the sheathing and cladding just right then it will be easy for the user to manually trim the secondary roof sheathing and cladding with my trim tool and then optionally union them up with the built in Union tool. I may need to make a video showing exactly how to perform this task.

 

[Medeek]

Version 1.8.1 - 01.29.2017
- Enabled gable wall cladding for common trusses.
- Added four "HARDIPLANK Cedarmill" siding colors into the wall cladding material library.
- Enabled sheathing and cladding for valley truss sets.

 

[Medeek]

The 18.5' highbay/garage only needs to be 16' in height and the 2nd floor of the office space needs 9 ft ceilings:

https://3dwarehouse.sketchup.com/model.html?id=cb53d8ed-8174-4cb1-a4cb-f2cff60679ff

Note the valley truss set, and how I was able to easily tie these two roofs together. For simple roof lines I'm pretty happy with what the plugin can do.

 

[Medeek]

In response to a recent request about gable ends of the roof assembly I have created an additional option in the "Gable End Trusses" option when creating common trusses. The new "Front" option only creates the gable end truss and gable end geometry on one side of the truss assembly and leaves the other side open as shown below:

This should come in handy when creating roof assemblies that **** up against walls and other complex configurations (ie. T-shaped buildings requiring Valley Sets etc...)

I've also been slowly working away at bringing all of the common truss types up to speed. The Modified Qeen Truss (Mod Queen) now has plates, raised heels, structural outlookers, layers and materials:

Most of the non-common truss types still need me to go through and integrate plates, layers, raised heels and materials, the amount of work needing to be done is staggering. This plugin is far from a polished, finished product, even after more than a year's worth of time and effort.

 

[Medeek]

The common fan truss now has raised heels, plates, materials and layers:

I apologize for the slow progress. I've had some 12 hour work days last week so I didn't have much left in the tank once I got home, usually just eat and then went straight to bed.

 

[Medeek]

Version 1.8.3 - 02.12.2017
- Enabled metal plate connectors, materials and custom layers for Fan trusses.
- Added energy/raised heels for Fan truss (3 variants: wedge, slider and vertical w/ strut).
- Roof slope can be toggled between Pitch or Degrees (input) for common trusses in the global settings.

Currently the metric template forces the roof slope to degrees however in the imperial templates (inches, feet) the user can select between Pitch or Angle for common truss types. I will need to update all of the truss types with this global setting option.

 

[Medeek]

To create this roof was not an entirely automated process but I'm slowly getting there. The trim tool comes in really handy for creating valley and jack rafters but ultimately it would be nice to auto create L-Shaped, T-Shaped and U-Shaped roofs.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=28c0e0f9-a245-4ff9-a923-f8c268bc9828

 

[Medeek]

 

[Medeek]

Version 1.8.5 - 02.18.2017
- Enabled roof cladding for dutch gable and TJI rafter roofs.
- Added TJI rafter roofs with dual glulam beams.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=82a033b2-acc6-4216-a04c-f3707c68a49e

First new roof type in added in quite a while. Lately I have been focusing most of my effort on cleaning things up and making sure all the options are working correctly for each roof type and configuration.

 

[Medeek]

Trying out the Rayelectron Rendering plugin, I'm fairly impressed.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=3cbb85a2-7f92-426c-995e-65262991accc

 

[Medeek]

An example dormer created with the dormer tool and the gable roof created with the common truss tool. Note that I have enabled all of the cladding, sheathing and GWB in the global settings.

View model here:

https://3dwarehouse.sketchup.com/model.html?id=2ff7c406-7fe4-44af-b6ed-c4c817122285

When you select "YES" for the gypsum ceiling in the advanced options of common trusses and additional dialog is presented which then allows for manually adjusting the GWB thickness, ext. wall inset, and ceiling battens (size, spacing).

You will notice that in the global settings within the "Sheathing" tab a couple of new items have been added for Gypsum Sheathing.

Now I just need to enable ceiling sheathing for vaulted truss and rafter roofs, yet another large task added to the todo list.

Attic and Gambrel attic trusses will require not only ceiling GWB but also the attic GWB on walls and flat and sloping ceilings.

With the addition of all the interior and exterior cladding, the plugin can now generate the majority of the structural features of a roof.

 

[Medeek]

Raised heel fink truss roof with 1.5"x1.5" ceiling battens and 5/8" GWB at a 5.5" wall inset.

 

[Medeek]

I've been giving some though to the soffit and fascia and I realized that in many cases the design may call for a closed soffit:

I've seen soffits constructed with plywood and also metal (aluminum, vented).

Also the fascia I am creating currently should be more properly labeled the sub-fascia since in many cases the true fascia board is a thinner 5/4 or 1x material. If metal is used then the sub-fascia is covered over with a fascia cover:

Then of course we get into the whole boxed soffit at the corners:

I would like to get some input in what you would like to see with closed soffits and fascia. I am thinking it might be useful to have a completely separate section in the global settings that deals specifically with closed soffits, fascia and corner treatment (ie. boxed corners vs. non-boxed)

 

[Medeek]

Medeek Truss vs. MS Physics:

Pretty clear the house didn't have a chance.

I'm actually very impressed with the collision detection of MS Physics, an amazing extension.

 

[Medeek]

I've been reviewing my Todo list lately and it really hasn't shrunk much, if anything it has grown a bit as I've added some new features in the last month and more catching up needs to be done with various truss types.

I only work on this project part time and on the weekends as much as possible, so my progress since September of 2016 has been quite slow (took a new job with the City of Ocean Shores).

Currently the Truss Plugin has seen the most development but I am also spread between the other separate plugins as well:

Medeek Wall Plugin
Medeek Structural Plugin
Medeek Foundation Plugin
Medeek Deck Plugin

The structural and wall plugins will be just as complex and involved as the Truss Plugin and will require a couple years of my full time attention to get where they need to go.

When I step back and look at everything I want to accomplish there is just no way, given my current situation, that I can achieve it. It would be nice to also be able to hire some help in knocking out some of the coding, realistically there is only so many hours in a day and only so much one person can do.

I would really like to work full time on all of this as I see it has some serious potential and I'm also very excited about it but my previous attempt at using KickStarter to raise some working capital did not amount to much.

I was watching Shark Tank last night and I was thinking would this type of business even have a chance in that setting? Anyhow, I am open to any ideas you might have in how to really blow this thing up and get it going.

 

[Medeek]

Version 1.0.9 - 03.25.2017
- Added slab foundation type (rectangular outline only).
- Enabled full and partial width interior thickened slab footings.

 

[Orionrising]

ever played with an open gambrel truss?
similar this in concept
http://www.kelleytruss.com/wp-content/uploads/2015/01/Open-Gam.png
I am debating if the floor truss is functioning as a rafter tie or not ( have a garage roofed by some made by a now defunct company)... that they did not leave a floor opening for a stair.... easy solution is to cut out two spans of the floor truss... probably not the correct solution though...

 

[Medeek]

Version 1.8.8 - 04.28.2017
- Added energy/raised heels for mod fan truss (3 variant: wedge, slider and vertical w/ strut).
- Metal plate connectors now enabled for mod fan trusses.

 

[Medeek]

**Fun with Roofs - Episode 1**

My 9 year old son took one look at this roof and then said "Don't build this in Florida, you'll create a sink hole".

View model here:

https://3dwarehouse.sketchup.com/model/2032fed3-cb9b-40c4-80b1-be1009b3f022/Residence-8

 

[Medeek]

Version 1.8.9 - 05.01.2017
- Added energy/raised heels for triple fink truss (3 variant: wedge, slider and vertical w/ strut).
- Metal plate connectors now enabled for triple fink trusses.

 

[Medeek]

I've got to fix my wife's computer today so that will probably stop me from getting any real meaningful work done on the plugins but at least I've been able to throw together a first draft for the office I want to build. Any thoughts on improving the design, sometimes once you get an idea in your head it is hard to see outside the box.

I haven't shown the doors or the front porch which will probably be quite small and pressure treated lumber.

- 32'x24'
- 5:12 or 6:12 roof with asphalt shingles
- two rooms
- 9' ceilings
- stemwall foundation with crawlspace
- carpet throughout
- 5/8" wallboard
- 3068 doors, (1) 4040XO, (3) 5040XO
- 11-7/8" I-Joists at 16" o/c
- studs DF No. 2, 2x6 @ 16" o/c
- sheathing will probably be 1/2" plywood, I don't like OSB in our climate.
- Siding Hardiplank or cedar siding, my budget may call for T11 though.
- Electric wall cadet heaters
- 50 AMP sub-panel from house
- 16" overhangs at eaves and gables with gutters and downspouts and 4" drain lines away from building.

 

[Medeek]

All the end details are working. This is an example of a Mansard Parapet truss with 5 panels and different overhangs:

Now I just need to work on the plates and advanced options.