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Modeling
About Archicad's design tools, element connections, modeling concepts, etc.

Roofmaker issues

I recently submitted an issue I was having with the Trusssmaker tool to which Karl O was nice enough to provide some feedback. So instead of a truss I decided why not just use rafters of a necessary size and optimal spacing. After reading through all of the instructions on creating a rafter(s) I did the following. I first selected the roof in the layout mode. Next I selected "Design, Roof extras, Roofmaker, Create a rafter) and the rafter details window pops up. I set all of the options to what I need and finally click on OK. I am now requested to select a point anywhere inside the area of the roof to place the rafter which I do. I next opened the 3D view and to my surprise the rafter is in the spot selected but instead of following the underside of the roof it is horizontal to the ground. Can't understand the result as I did everything as stated in the AC help documentation. Don't know what I did wrong. All help appreciated. Regards

4 REPLIES 4

I was wondering if my problem has to do with my roof selection was "Generic 10" : R01" which presents as a slab in 3D. It got me thinking that there should be more options to choose, such as rafters, shingle, outside surface (3/4" plywood) etc when creating a roof. The current "options" on what type of roof to use seems very limited. regards

Karl Ottenstein
Moderator

I can't see any issues with Roofmaker as you described and wonder if you're sure that just the roof was selected, and not perhaps a ceiling that was modeled with the roof tool?

 

I magic wand-ed a hipped roof around an L shaped slab, selected the roof, used the Roofmaker Wizard with default settings, and everything was created as it should be.

 

I should let you know that Roofmaker has also not received a huge amount of development in the past 20 some years, similar to Trussmaker.  It does recognize multiplane roofs now, which is great, but the biggest improvement I see today is that if you use the editable hotspots (fuschia diamonds) for rafters to increase the length... they actually work.  In years past, making a beam longer changed its pitch, which was crazy.  I have no idea when that was fixed as I haven't touched RM in years.

 

I'm not sure what you mean by 'more option' such as 'shingle, outside surface' etc.   Anything to do with sheathing and shingles is part of the roof plane.  Roofmaker only creates structural members... see the options in the Wizard.  Or are you referring to the Roof Tool itself needing more options?  The options are unlimited...create your own composite with whatever you need.  If you really need to model down to the level of shingles (ovelapping drip edge/faschia) for example vs structural sheathing/weatherproofing, then you'll need two roofs on top of each other - one structural, the other for the finish.

One of the forum moderators
AC 27 USA and earlier   •   macOS Ventura 13.6.6, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB

Hello Karl:

To make it easier for you to understand what I am doing I have included a picture of the steps I took and the end result. Please note that the roof was created using the roof tool. In figure 1 you will see the back side of the building (halfway house on a golf course), the roof is blue and you will see that there aren't any rafters under the roof. Figure 2 shows the selection of only the roof in plan view. Figure 3 shows the steps taken to get to the "create multiple rafters" tool/window. Figure 4 shows the selections I made for my application. Figure 5 shows the rafters in the plan view. Finally figure 6 shows a picture of the back of the building (3D view) and the result which shows the rafters place horizontally and not along the underside of the roof. It's like AC thinks the roof is flat which it isn't.

rafters example.jpg

It doesn't appear that I did anything wrong.

 

As for the extra options I didn't know that the roof structure and "skin" were 2 separate functions. Most roofs I create are for large flat roofs which only requires a slab for presentations. As for me I think complete roof results when using the "Roofmaker" tool, it makes the whole roof not just the structural elements but the "skins" (Tar paper, rubber underlayment, shingles (tar, steel or clay), and so on. So in order to do that it would be nice if a window popped up with several tabs like the roof wizard where the user could select the appropriate tab then select all of the desired needs. As an example, One tab could be "shingles" where the user can select the type and sizes of individual tiles. In actuality, the rafters wizard would make a great starting point to which more tabs could be added. And instead having the typical properties window open when the tool is double clicked a window like the one used by the roof wizard. The user can then select all the properties if the roof and then select the co-ordinates of the roof's perimeter and click OK. The wizard would create the roof in full with all the details that would allow the user to generate a BOM for the roof's required materials. That's my way of thinking. If you have a wizard then it should do everything.  Anyway,

regarding the first part, can you see where I went wrong? Thanks and regards.

I can't reproduce what you show.  (I can't read everything that you posted due to low res - but good enough.  Thanks for making such detailed screenshots.  In future, drag each one individually - no limit to quantity - into your message so that they can be full res/readable.)

 

Beams run with the slope of a roof, so it is odd to see your beams run parallel to the slope... although they aren't sloping, which is the issue.

 

Again, I find the Roof Wizard  works fine on this - but get the same result with the Create Multiple Rafters.  Of course, RM falls down on understanding the parts of the roof that overhang the structural/supporting walls - as it will generate rafters that just hang in space. There would have to be lookouts for the north/south edges penetrating well into the building where a joining rafter would have to be doubled up or even beefier.  And either the rafters would have to be beefy, or there would have to be an intermediary beam for the long room on the bottom right of your plan view.  RM doesn't understand structural loads - just tries to give a starting point for preliminary design visualization pending the engineer's plan.

 

One of the forum moderators
AC 27 USA and earlier   •   macOS Ventura 13.6.6, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB
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