wall and roof structure modeling

[Anonymous]

I'm working through my first full project (residential) with AC and so far it's gone pretty well and I'm thrilled with AC over my previous software -Arch. Desktop.

I've got a plan in mind for building the model, but wanted to run it by the more expert minds here and get some feedback if possible.

I'm using composite walls with core fills and outer fills representing drywall and exterior sheathing. On top of that, I'm was planning to use the cadimage accessories tool to add exterior finish materials - clapboard, stucco, etc. To follow the way it's built, I plan to have the floor slabs follow the perimeter of the core and then add thin walls to the exterior faces of then to create a continuous sheathing plane.

I think that this is going to work, but can't figure out what to do at gable ends.

Here's why - Following what I've read in other threads, I'm planning to use the roof tool to create the structural part of the roof and then the cadimage accessories and/or complex profiles, beams, roofs, etc. to create the soffits, eaves, moldings, etc.

So right now I've got a composite wall with set to trim to the roof above and that roof is set back in line with the core of the wall. Like the slabs, I need to face it with sheathing but I'm not sure how since it appears that wall can angle the bottom edge. I can use beams, but it seems that when I go to face all the sheathing with the cadimage wall accessory, that the beam won't work. Does anyone know if that's the case? Unfortunately my cadimage demo period ran out before I got to this point and I want to make sure I have a workable plan before paying for it.

So first question is does this approach makes sense or is it overly complicated and asking for trouble? (For construction drawings, I really don't need this much section detail but it seems needed for 3D, for nice elevations, and having full thicknesses is good for interior planning as well.)

And second question is how to make it work at those gable ends? The only other think I can think of is using the same sheathing-width walls as on the slabs and then using SEO to cut the top and bottom but I hate to think of what I'd have to do each time the pitch changes.

Obviously it would be really nice if the roof tool integrated eave and soffit details and the walls trimmed accordingly but I guess that will have to wait for another day.....

Any help and thoughts are much appreciated! Thanks, Chris

(hopefully when I get a little further along, I'll be able to answer more and ask less but I'm working on it!)

[__archiben]

Chris wrote:
Well, I'm almost talking about the barge-board, but in this case the eave and bargeboard are of a smaller dimension than the roof structure. Since I'm planning on using the cadimage accessories to add clapboards to the walls, I therefore need a wall object in front of the roof (where the sheathing will be in reality) so that I can attach the clapboard wall object up to the bottom of the barge board.

not really - just set the wall builder to 'follow...' the top of the wall and offset it down by a negative amount. the wall cladding will then extend upwards from the actual top of wall. (in reality it's going to slide underneath the barge flashing anyway right?). and then configure the barge flashing to extend out over the cladding.

Since I am planning to use the cadimage accessories for eaves and soffit - how do you find them? Any giant hits or misses with the tool?

i find them far more satisfying than working solely with the archicad toolset. there's something a bit more 'BIM' about working with them: there's little fudging - you have to solve the details.

but like all add-ons - especially the ones that rely on graphisoft's own accessories framework - they are quirky and take some patience to master. you often have to do a little sideways thinking to get the best out of them (like the negative offset down above) . . .

good luck . . .

~/archiben

[Anonymous]

Thanks for all the input and advice - thought I'd share a method I just worked out that seems to work (at least so far....)

1. Composite wall with core (2x6's) and 3/4" outer sheathing section
2. Roof representing the structural members only, lined up with the wall core.
3. Another roof representing the roof sheathing directly on top and overhanging as needed for the eaves and rakes.
4. Use SEO subtraction with upward extrusion (wall as target, roofs as operators). The first roof, trims off the core portion of the roof leaving the sheathing to continue past and be trimmed by the second roof.
5. Use cadimage accessories to apply outer wall and roof sheathing and other details (once I get the hang of the eave, barge, rake, etc. functions that is...)

This might be what was described the earlier responses, but I was so focused on my little path walls of sheathing to be applied to the face of slabs and roofs that it all didn't click until just now.

[__archiben]

Chris wrote:
This might be what was described the earlier responses, but I was so focused on my little path walls of sheathing to be applied to the face of slabs and roofs that it all didn't click until just now.

you've got it!

a wise man once said, "Build it like they build it except when you can’t."

~/archiben