topic Re: Eaves depth in Modeling

Eaves depth

Anonymous — Tue, 23 May 2023 12:19:14 GMT

Hi!

If I have an insulated roof, at say 300mm deep, when it gets beyond the external wall I need it to be shallower so that I don't have a massively deep fascia.

What is the cleanest most efficient way of doing this?

Re: Eaves depth

gpowless — Sat, 17 Dec 2016 12:39:29 GMT

For cathedral ceilings like that I model the roof & the sloped ceiling separately. This allows the rafter tails to extend beyond the walls & keeps the ceiling inside of the conditioned space.

Re: Eaves depth

Anonymous — Sat, 17 Dec 2016 13:10:48 GMT

Cool thanks.

So would you then effectively have 2 roofs one on top of the other?

Re: Eaves depth

Richard Morrison — Sat, 17 Dec 2016 18:53:04 GMT

You might also look at Eric Bobrow's approach which uses SEOs and gives you more flexibility. https://youtu.be/lmgGoPhvl_Q

Re: Eaves depth

Anonymous — Sat, 17 Dec 2016 19:19:53 GMT

Richard wrote:
You might also look at Eric Bobrow's approach which uses SEOs and gives you more flexibility. https://youtu.be/lmgGoPhvl_Q

That's awesome, thank you!

Re: Eaves depth

gpowless — Sun, 18 Dec 2016 12:51:33 GMT

zak1607 wrote:
Cool thanks.

So would you then effectively have 2 roofs one on top of the other?

Yes. The ceiling pivot is placed at the inside of the wall and the roof pivot line is placed on the outside. This also works with scissor trusses or coffered ceilings where the interior ceiling is at a different pitch than the roof pitch. The ceiling of course consists of the ceiling finish and insulation. The roof composite contains the shingles, sheathing and top chord of truss / rafter. I also have a composite that I use for the minimum ventilation / thickness at the eaves and then SEO the ceiling insulation.

Re: Eaves depth

Anonymous — Tue, 20 Dec 2016 11:56:02 GMT

Brill thanks

Re: Eaves depth

Steve Jepson — Tue, 21 Feb 2017 04:51:34 GMT

Re: Eaves depth

Steve Jepson — Tue, 21 Feb 2017 05:40:02 GMT

Model your roof just like it will be constructed.

Re: Eaves depth

Anonymous — Tue, 21 Feb 2017 17:19:52 GMT

Thanks Steve,

Though that's probably more effort than I'd want to put in for planning drawings, that's definitely what I'd do for regs/construction drawings.

Re: Eaves depth

Stress Co_ — Tue, 21 Feb 2017 19:25:05 GMT

Steve wrote:
Model your roof just like it will be constructed.

Nice work Steve. Must make sections a breeze.

But...Looks incomplete.
You didn't model all the nails.

Re: Eaves depth

Steve Jepson — Tue, 21 Feb 2017 20:20:17 GMT

zak1607 wrote:
Thanks Steve,

Though that's probably more effort than I'd want to put in for planning drawings, that's definitely what I'd do for regs/construction drawings.

I know what you mean.

Re: Eaves depth

Steve Jepson — Tue, 21 Feb 2017 22:05:37 GMT

Stress wrote:
Steve wrote:
Model your roof just like it will be constructed.
Nice work Steve. Must make sections a breeze.

But...Looks incomplete.
You didn't model all the nails.

Of course I did. Sort of

I optimize the layout start points for everything too. As you can see in this drawing even the scrap is accounted for. This drawing was revised to use ring shank nails and the order and the schedule was in nail clips rather than pounds.

Re: Eaves depth

Richard Morrison — Wed, 22 Feb 2017 00:29:00 GMT

And just when I was starting to feel good about my ArchiCAD skills....

Re: Eaves depth

Erwin Edel — Wed, 22 Feb 2017 08:49:30 GMT

You can merge two roofs, so you can have two composites of different structure for the part that extends outside. Select both roofs, right click, connect > merge elements.

Since the top layers of your composites will be the same, you will not see any lines in plan view. Elevation/section will look fine too, but ussually just having the same surfaces will solve this.

The problem with SEO is that you end up cutting away bits of the composite that you do not want to lose, generally.

This also works with shells.

Re: Eaves depth

Steve Jepson — Wed, 22 Feb 2017 19:01:13 GMT

Richard wrote:
And just when I was starting to feel good about my ArchiCAD skills....

If there was a place on this Forum for showing off I have some interesting stuff I would post there.

Here is link to a video of a lumber take-off I did for an unusual house with double wall framing at the exterior. I should say that there are no lines here. Everything is modeled. If I need a line to show up somewhere in a drawing I use a morph. I try to use no lines anywhere in the project.

https://www.screencast.com/t/U4O0m34Dri

Re: Eaves depth

Richard Morrison — Wed, 22 Feb 2017 19:13:03 GMT

Steve,
I can get worn out just LOOKING at your stuff.

Re: Eaves depth

Steve Jepson — Thu, 23 Feb 2017 01:28:22 GMT

Richard wrote:
Steve,
I can get worn out just LOOKING at your stuff.

And for what right? The truck from the lumberyard comes by on Thursdays to take back what you didn't use for a credit, and bring more if it was not enough.
Construction costs are not based on the material cost anyway. They are based square foot pricing or what ever the houses next to it was appraised for. Why worry about knowing exactly what the actual quantities will be?

Besides, the lumber yard has some very good take-off software and they will be happy to do the take-off for you and give you a firm price for the entire project, based on the volume of the project materials, and perhaps on the volume of other projects you have brought to them in the past.

I know, I have built many homes that way.

And I have also built many homes using my own hyper-detailed Plans and Material lists. For me, there is a significant value in what I am doing.

But for the builder who does not have a crew that could follow the plans anyway, they are useless. Actually offensive, because nobody likes to be told how to build every tiny detail.

I see it this way - every project is different. What is appropriate and useful for one project is a total waste of time for another.

But modeling the framing in detail ( for those rare times when it is useful) is not really as much work as it may look like. I work with premade assemblies of things that are just tweaked a little for each new situation.

Those wall framing plans for example are mostly from another project. You show the elevation as Trace behind the wall framing parts and slide the door and/or window assemblies (headers parts, king studs, trimmers, cripples, sill...) to the new location. Then move the sill to the new height, shorten the cripples. It really only takes 10 minuets or less so to model the framing in a wall. And the schedules are all automatically populated. There are ArchiCAD tools that can frame the walls automatically, but they take longer to configure than it does to model it. Also, the automatic framing is never quite right. Just like the Stair Tool. Never quite right, and modeling it out of some other stair is probably faster and produces shop drawing details and schedules.

To model the whole house framing like I do would be a heroic task. But I am doing this with the benefit of hundreds of completed ArchiCAD projects as a source for the assemblies.
I almost never model anything new. It is just a matter of tweaking something I have already done to fit the new situation.
This saves me so much time that I can afford to keep adding a little more detail, and a few more schedules to every project. Every project now is very detailed and with less time and effort on every job than the last one.

Re: Eaves depth

Anonymous — Thu, 23 Feb 2017 11:50:42 GMT

Even still, the level of detail you've got there is glorious and gives me hope that one day I might be able to get more finesse in my models rather than the ham fisted bodges I resort to now!!!!

Re: Eaves depth

Steve Jepson — Thu, 23 Feb 2017 17:48:37 GMT

zak1607 wrote:
Even still, the level of detail you've got there is glorious and gives me hope that one day I might be able to get more finesse in my models rather than the ham fisted bodges I resort to now!!!!

Here is a tip. The trusses profiles are all made with one click The magic wand! I use the MiTek truss profiles from the manufacture to make them.
The reason is that I like to make sure they all fit as expected. Not all of the truss manufacture technicians are as careful as they should be.