Author Topic: Truss Calculators  (Read 376850 times)

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Offline Medeek

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Re: Truss Calculators
« Reply #775 on: February 20, 2018, 08:30:25 AM »
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.

Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #776 on: February 20, 2018, 11:57:44 AM »
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:

https://forums.sketchup.com/t/right-click-menu-items/54916

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.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #777 on: February 26, 2018, 07:46:48 AM »
Making some good progress on the "edit" function.  I will initially start with the common trusses and then once I am satisfied that those trusses are running stable I will begin to make this feature available for all other truss, rafter and floor assemblies. 

I'm a little bogged down with the advanced options (there are too many) but it is just a matter of putting in the time and slogging through all of the data entry and HTML and javascript.  Probably by the end of the week I should have something ready to go and I will roll a release so everyone can begin testing it.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #778 on: February 26, 2018, 11:06:30 AM »
Has anyone had much experience with SIP walls?  I've been looking at the product offering of Eco Panel:

https://www.eco-panels.com/

and I am fairly curious about this product.
Nathaniel P. Wilkerson, P.E.
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Offline Don_P

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Re: Truss Calculators
« Reply #779 on: February 27, 2018, 03:10:25 AM »
A little, not these and a decade ago so this is just fodder. Things learned; check and double check rough openings, nothing worse than walking up to an opening with the window in hand and it won't fit. I then had to go back through engineering to modify the panels. Homeowner wanted to add some outlets after the fact, same issue. When I opened up the panels I found voids in the insulation, these were third party inspected, well so much for that. I decided I would want thermal imaging proof if I used them again. The panels were not truly flat, the curing process had left them thicker around the edges than in the field, noticeable on the roof and longer walls. We had to stop in high wind and then bring the crane back out, ka-ching. I'm not in love with hanging siding or anything on just osb. Inside we had a dropped ceiling in one area, there is no framing in the SIP to attach something like that to. At a quick look it appears there are no opening bucks in these, what is door/window attachment, people hammer doors. When you lose a skin to decay you have lost the integrity of that section, greater disturbance of the home vs resheathing and residing over a frame. I do really like the concept but it does require good foresight in the detailing.


Offline Medeek

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Re: Truss Calculators
« Reply #780 on: March 01, 2018, 11:15:12 PM »
Looks like I have the soffit cut function working for the hip rafter roof:



I will roll this out on the next release.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #781 on: March 01, 2018, 11:16:57 PM »
These SIPs sound like they are more trouble than they are worth.  I just really don't like the idea of there not being a "skeleton" to the structure. Your right if the OSB or plywood is damaged then there is really nothing solid holding your house up, it doesn't sit well with me.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #782 on: March 02, 2018, 05:31:26 AM »
Version 2.1.6 - 03.02.2018
- Added Soffit Cut within Advanced Options for Hip Rafter Roofs.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #783 on: March 03, 2018, 01:59:43 PM »
Version 2.1.6b - 03.03.2018
- Added Soffit Cut within Advanced Options for all Shed type Rafter Roofs.
- Added gutters for all Shed type Rafter Roofs.

Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #784 on: March 05, 2018, 07:22:54 AM »
The edit feature is slowly coming to fruition.  I've added so many advanced options to the common truss type that it is quite an ordeal to even put together the HTML form that fully encompasses all of this information and does it in an organized and neat manner.  There is a possibility of 72 unique (user entered) parameters for a common truss assembly.  Some of these are dependent on others, its an interesting web of dependencies (spaghetti) that must be taken into account for the edit feature to work properly.  I've probably got another week just in debugging before I am ready to release the first version of this feature.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #785 on: March 06, 2018, 09:59:39 PM »
Version 2.1.7 - 03.06.2018
- Enabled the "Edit Truss Assembly" function for all common roof trusses (imperial units only).

To edit a roof truss assembly just right click on the assembly and select the "Edit Truss Assembly" option. 

Note, that this function is only available for common trusses with imperial units (template).  Metric will be next.

It seems to be working fairly robustly but I'm sure there will be some minor bugs that pop up considering the complexity of the code and the sheer numbers of variables that I am working with.

Please report any errors by using the ruby console to record the error and email it to me.

Once this feature has been out for a while as I know it is running fairly stable I will then work on updating all rafter and truss assemblies so that the user can edit them.  I can already see that this will be a very useful upgrade to the plugin.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #786 on: March 07, 2018, 05:43:33 PM »

Below is a screenshot of the edit panel:

Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #787 on: March 10, 2018, 08:24:00 PM »
Tutorial 7, Edit Function and some changes to the global settings:

https://youtu.be/RWoyZJg6RcQ
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #788 on: March 11, 2018, 09:12:33 AM »
Version 2.1.7c - 03.11.2018
- Added ceiling gypsum and ceiling battens to cathedral trusses.





View model here:

https://3dwarehouse.sketchup.com/model/b689837e-5378-4b28-adaf-12367154ba2c/Cathedral-Truss-with-Ceiling-Battens
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #789 on: March 11, 2018, 06:59:12 PM »
I've been giving some thought to framed openings in floors, see image below:



Generally, at least from what I've seen most holes in floors are either rectangular, L-shaped or U-shaped, but I guess any outline is possible.

What I've shown in the image above is LSL or LVL framing out the opening however the actual framing might be significantly different depending on what is supporting the floor below.

In some cases the rectangular opening might not be supported by bearing walls from below, in that case the two LSL boards running parallel to the joists would probably be larger beams and the headers would be hangered from these beams and would also probably be more substantial.

The point is how to make this feature flexible enough to accommodate most framed openings but at the same time keeping it as simple as possible so the user is not overwhelmed with parameters.

View model here:

https://3dwarehouse.sketchup.com/model/a879f0c7-0900-47f5-9caf-acc1c3a53f25/Framed-Opening-TJI-Floor

Any ideas would be greatly appreciated.

P.S. I am also going to make this feature editable so that the actual hole can be altered after the fact.  This should be an interesting programming challenge.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #790 on: March 12, 2018, 09:26:40 AM »
Alternatively that same opening could be framed as below:



For the size of the opening one would probably use some PSL or LVL Beams rather than a couple of I-Joists but the concept is the same, compare with the previous example where the opening would probably be supported from below by bearing walls.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #791 on: March 15, 2018, 06:25:40 AM »
Version 3.1.7d - 03.14.2017
 - Addresses a minor bug with the UI menu for common trusses.  The overhang of the truss could be rounded to an integer value upon recreation of another truss set.

I wonder why no one else has noticed the overhang rounding issue.  I just realized it is an artifact from when I had it setup to use a integer value for the overhang, which I eventually changed but I must have forgot to update the rounding function (or remove it) so that non integer values could be input.

It appears this bug only affected common trusses but I will need to go through and check each truss type to make sure the same issue was not replicated elsewhere.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #792 on: March 16, 2018, 06:21:29 PM »
Two different ways to truss out a dutch gable roof:





The first method involves a wailing plate attached to the side of the girder truss.  This appears to be the preferred method of construction in Australia.

The second method employs vertical studs on the gable end portion (upper half) of the girder truss.  What is not entirely clear to me is how the joint comes together at the top chord where the horizontal member (at the top of the jacks) meets the vertical and diagonal web of the girder truss.

I could really use a shop drawing (2D) of this particular configuration.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #793 on: March 18, 2018, 09:18:42 AM »
Version 2.1.8 - 03.18.2018
- Enabled the "Edit Floor Assembly" function for all I-Joist floors (imperial and metric units): TJI, BCI, LPI, Red-I, PKI.



Now I just need to get the floor framed opening feature working and then this module might actually be useful.

Realize that any manual edits made to the floor assembly are blown away when you use the edit function.  It is essentially re-drawing the entire floor assembly, the same goes for the roof truss assembly edit feature.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #794 on: March 19, 2018, 08:19:43 AM »
Spending some time the last couple of days thinking about the floor module (floor trusses, I-joists, solid sawn joists).

The obvious 800 lbs gorilla is the ability to easily add openings into these floors. The other missing element is the ability to create a polygon shaped floor (something beyond a rectangle outline). 

With regards to polygon shaped geometry I've already done the heavy lifting when I programmed the foundation plugin to generate polygon shaped layouts (slab and stemwall).  The details in trimming the joists is also mostly figured out since my rebar and mesh routine for slabs utilizes a function that will form the basis for this function.  It is really just a matter of finding the time and then digging into the code deep for a solid 12+ hour period (uninterrupted).

These two issues are my main focus the next week or two. If I can address both as well have the edit function work seamlessly with both then I will have created an actual functional floor module.
Nathaniel P. Wilkerson, P.E.
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Offline Medeek

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Re: Truss Calculators
« Reply #795 on: March 22, 2018, 04:30:35 PM »
I've been looking at adding in the ability to handle dual pitch hip roofs:



View model here:

https://3dwarehouse.sketchup.com/model/745938a9-71cf-4fef-8db1-e9ebc305f839/Hip-Roof-Dual-Pitch

The first thing that jumps out at me is the jack rafters do not line up when the pitches are different.  Also if the overhang is the same and the fascia is the same height then the top plate will be a different height for the different pitches.
Nathaniel P. Wilkerson, P.E.
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Re: Truss Calculators
« Reply #796 on: March 23, 2018, 03:59:21 PM »
With dual pitch hip roofs technically one could have a different pitch for all four sides (the most general case).  I should probably try to code this most general case then all the rest simply fall out of it.



View model here:

https://3dwarehouse.sketchup.com/model/6acf80ad-85ed-4096-b51e-4f55646aabac/General-Hip-Roof

I'm not sure why one would want to construct a roof in this manner but I guess I should probably allow for the possibility.
Nathaniel P. Wilkerson, P.E.
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Offline Don_P

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Re: Truss Calculators
« Reply #797 on: March 23, 2018, 05:09:36 PM »
It's been quite awhile but I've done 3 sides of that wrapping a porch around a house at different pitches. The lack of alignment of jacks, they don't "shake hands", is one reason I like to double the hip. You can often maintain plate height and overhang by moving the hip around the corner, drawing from the fascia back.

Offline Medeek

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Re: Truss Calculators
« Reply #798 on: March 24, 2018, 01:57:20 AM »
It is certainly an interesting puzzle.  Calculating the commons, jacks and hip rafters is not a problem, I can figure that out.  The one item that has me though is the fact that if each pitch is different and assuming the same overhang all the way around and the same birdsmouth cut then the top plate of each wall will need to be slightly different.  Again I can make that adjustment for each side of the roof for the commons and the jacks.  The real question then is what to do with the birdsmouth cut of the hip rafters?  Which wall height does one use?
Nathaniel P. Wilkerson, P.E.
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Offline Don_P

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Re: Truss Calculators
« Reply #799 on: March 25, 2018, 11:46:13 AM »
I try not to change the wall heights, I play with the HAP first, adjust the birdsmouths, the heel height. This is a quickie 8/12 and 4/12, 2' overhangs, same level plates. Drawn from the gutter line. The hip drifts out of the wall corner to the steep side, that answers one question I think. Notice my 4/12 is notched well beyond code. It is iterative when it does work. In the hip I've often ended up with a dragon beam sitting on the wall across the corner diagonally that the hip rests on or against with hangers, then continue with a smaller section out over the wall to the fascia.



A dragon beam, This avoids a long birdsmouth inboard of the bearing. The hip got a double hanger prior to buttoning up the ceiling;


« Last Edit: March 25, 2018, 01:16:08 PM by Don_P »