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Messages - Medeek

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When the plugin is loaded in a metric template it will now utilize a web dialog with metric sizes for glulam beams.  The menu and glulam beam sizes are currently listed at the following link:

I probably don't list every combination possible or manufactured in each respective country or jurisdiction but hopefully I list the most common sizes.  So far I have entered in data for the United Kingdom (Great Britain), South Africa, and Australia (and New Zealand). 

I can enter in more countries if provided the data (width, depth, locale name and ply thickness).  Now that I have the web dialogs and html files setup it is not a big deal to add more entries.

When the plugin is loaded in inches or feet then the US sizes or AWC NDS tables are loaded.  So far I have only found one country that still uses the old units.

With I-joist roofs don't think I would model in any of the web stiffeners, otherwise the model gets too heavy, same goes for small fasteners and hangers. 

I haven't even considered the option yet with the rafters resting on top of the beam (dropped ridge).  The I-joist manufacturers do not allow notching at the top end and therefore a beveled bearing plate or strip is required with web stiffeners on both sides of the I-joist.  Their detail shows a strap across the tops of the I-joists tying them together across the beam, I'm pretty familiar with this detail from some local jobs I've done recently. However, I'm also wondering about the beveled strip on top of the ridge beam, how is it made, thickness at the butt etc...

With common sawn rafters how would you typically handle a dropped beam?  Would you use a beveled strip or would you apply a  birdsmouth cut at the ridge?  I think I've seen both details but what is the preferred method if there is one.

The problem is I'm not out in the field enough so I never get to see this stuff actually go together very often.


I remember a few years back when I was in college and working a side job as a construction laborer we framed up a roof similar to this.  The rafters were large I-Joists (TJI 560 equiv.) and were hangered from the glulam beam.  The beam was probably almost 2 feet deep.  I just remember I was glad I was cutting the blocking on the miter saw and not the one at the peak of the roof setting the rafters into the hangers. 

With that being said I am wondering how often I-Joists are used in this type of application versus common lumber.  I can probably add in an option to use them instead of common lumber.  One question I have though is what to do at the other end, where they bear at the wall.  I would need to study this further.


I've added an extra input for the beam which allows ones to specify the overhang of the beam from the outside of the wall.  With zero overhang the beam will be flush with the wall framing and not exposed.  If the beam overhang is less than the gable overhang, the fly will be as shown below (up to the roof peak).  If the beam overhang is greater than the gable overhang it will project past and the fly will adjust accordingly.  The beam overhang is not restricted in any manner.

Here is quick model of the wall framing associated with a gable roof with a glulam beam:

Beam Pocket with 6x6 post:

Gable wall and eave wall intersection:

Overview of Model:

Version 1.1.9 - 12.10.2015
- Added Gable Rafter Roof with Glulam Beam (all advanced options enabled).

I'm wondering with my rafter roof if I should provide an option to draw ceiling joists?

With regards to the configuration of the outlooker near the outside corner of the roof, to be perfectly honest I've actually never given it too much thought other than I've always seen it framed that way.  I suppose one could frame a diagonal outlooker to fully catch the corner but in that case then the other two would be cut short.  My theory is two fold:

1.)  The weight of the gutter and rainwater make the eave more heavily loaded.
2.)  The sub-fascia is being supported by the rafter tails which is turn is holding up the lower end of the barge board.  As such I would think one would want to provide support for the sub-fascia as close to the corner as possible.

The corner could probably be framed out either way, one of the boards ends up getting cut and does not provide much bending resistance.

Another thing worth noting is the rafter tails (with large rafters as shown) are usually trimmed to the bottom of the fascia or slightly higher and then a closed soffit is attached.  Since the rafters are components it is very easy to go in and make this trim cut to all the rafters so I leave it to the user to make this modification instead of another option.

On the same token the ridgeboard would probably be trimmed as well.  I need to look at that a little closer.

Admittedly the user interface is still very rough around the edges.  One thing I've started working on is making the default values assume the last values inputted by the user.  The code is fairly simple but updating all of the different menus is tedious because I have quite a few truss types now.  This should make creating multiple truss sets in a document even quicker since parameters like roof pitch, overhangs and heel heights are typically the same for a given structure.

To test this functionality currently, download the latest version 1.1.8 and test the common truss types (Imperial Units).  I will be updating all menus so that this functionality is present.

Version 1.1.8 - 12.08.2015
- Structural Outlookers enabled for gable rafter roofs (vertical & horizontal).

Notice in this case I have left the gable rafter in place but notched clean through it, so essentially it is blocking.  However, I have also given the option for removing the gable rafter entirely.  You will also notice that the gable rafter is the same depth as the outlookers, when you choose "CUSTOM" for the gable end rafter it allows one to specify the depth of this rafter. 

When structural outlookers are used in a vertical orientation it is common practice to have them bear directly on the double top plate of the gable wall (balloon framed to roof).  If there is some configuration that is standard in your neck of the woods that I am missing please let me know.  I am currently providing three different configurations for the gable end rafters.

I think I am ready to now attack the gable rafter roof with glulam beam.

Version 1.1.8 - 12.07.2015
- Added Gable Rafter Roof.
- Advanced options enabled for gable rafter roofs (sub-fascia, outlookers, sheathing, and rakeboards).
- New submenu item and toolbar icon added for rafter roof type.
- Plugin divided into multiple files for ease of management.

Structural outlookers for this type of a roof are still somewhat of a question.  If they are horizontal it makes sense to notch the gable rafter but what if they are vertical?

With the main roof sheathing:

Here is an example of a large valley set with a Monopitch Primary Roof and a Common Secondary Roof.  Notice the pitch of the monopitch roof is 6:12 while the secondary roof is 12:12.

Rather than calculate the overhang for the secondary roof it is just as easy to to trim the truss tails back and adjust the fascia so that it lines up with the fascia of the main roof after the fact.

Even with all the automation of certain tasks there is still a good bit of manual editing required when complex roof lines are involved however I find that SketchUp has a very intuitive interface for trimming solids and once the basic geometry is there the rest is usually not too much trouble.

This update was not that complicated (valley sets) other than trying to figure out how to place the set based only on a plane and two points. Obtaining this information and then figuring out the math and code to compute the vertical distance between the bottom of the first valley truss where it rests on the main roof plane and the peak of the secondary roof line was the slightly painful part. The actual geometry of the valley set was surprisingly easy to code.

The real challenge will begin when I try to add some hip sets, I may push that out for awhile.

I've addressed a few bugs with the valley set algorithm and tested it in as many configurations and orientations as possible.  It it more solid now.  I suggest downloading the latest version of 1.1.7 that I just uploaded to the server.

Note that the plane of the main roof that is selected needs to be a rectangular shape at the moment to properly register (1st point selected).  I usually just select the top face of one of the top chords of the trusses.  The second point should be at the centerline of the last truss of the secondary roof line and at the ridge (peak) of this truss, the third point is also at the ridge (peak) but at a point towards the main roof.  I really need to put the manual together to document this feature and how to use it, or at least a video. 

I also updated the geometry algorithm slightly so that it adds additional verts a 48" o/c when the valley trusses get too large.  This is keeping in line with standard practice on these types of valley sets.  I can also make this an input if someone requests that it be such.

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