topic Re: Plumb wooden Rafters in Revit Architecture Forum

Plumb wooden Rafters

Marie.j03 — Wed, 15 Jan 2020 22:51:54 GMT

I am working on a landscape project where originally the design was approved and issued for construction. Today the client's representative requested some amendments one of which is to change rafters on 12 gazebos to plumb (previously they were overhanging 70cm)

I changed 1 and sent it earlier in the afternoon for their review before we go ahead and unfortunately they liked it and now I have to change all 32 😕 they are circular and elliptical in shape (mostly circular), the rafters are wooden beams (arrayed) each has 16 rafters

I am trying to find a way to make them plumb cut without having to redo everything from scratch rafters, lattices, alignment, annotations and tagging. Something not so time consuming would be awesome.

Thanks

Re: Plumb wooden Rafters

ToanDN — Wed, 15 Jan 2020 22:55:02 GMT

Can you cut them with reference planes?

Re: Plumb wooden Rafters

RDAOU — Wed, 15 Jan 2020 23:01:03 GMT

Last minute changes are always annoying... I can think of several options/potential solutions for your case (not sure which is the most practical though:

Edit the rafter's family and add an angle/parameter to the extrusion then re-load and overwrite those in the model. Pretty much fast you will be done roughly in 5mins.
In conceptual mass environment model a mass (a hollow cylinder with Radius instance parameter to adjust if you have structures of diameter) >> load into the project and cut the rafters. You would need to ungroup the elements of the array which shouldn't be a problem if the structural design for the gazebo is done and you are not adding more rafters later
Use Dynamo (a similar solution to option 2 but faster)
Try what seemed to be a suitable solution for the OP on this link HERE (Edit: forgot to add the link - fixed)

If you need help with any feel free to ask

Good luck

Re: Plumb wooden Rafters

Marie.j03 — Wed, 15 Jan 2020 23:06:05 GMT

@ToanDN hi and thank you for the reply

No! I know how to cut rafters with reference planes and I really want to avoid it. It is lots of work because they are all radial and elliptical of various dimensions so I cannot even move and reuse the planes and because it cut them straight ... @RDAOU seem to have some ideas with potential I think I will try one of those and see how it works on one

Re: Plumb wooden Rafters

Marie.j03 — Wed, 15 Jan 2020 23:16:29 GMT

@RDAOU hi and thank you too for your reply

I already saw that link earlier today and I was using planes to do the first sample which I sent to the client. It is really not an option as I told @ToanDN doing with reference planes would too much, frustrating and doesnt cut the rafters properly to the circular form.

I think I will try the mass option first and test it on one gazebo, it seems easy and quick...I will let you know how it goes and thanks for your help

Re: Plumb wooden Rafters

ToanDN — Wed, 15 Jan 2020 23:22:33 GMT

You can also create thick circular or elliptical wall scoping the new perimeter, then use join geometry the walls and the rafters and hide the walls when done.

Re: Plumb wooden Rafters

Marie.j03 — Wed, 15 Jan 2020 23:37:49 GMT

@ToanDN I did think of this method. I saw it on a revit blog but I really don't want to add walls that we don't need. We are alread having a problem with 146 artist/feature walls across the park which I will explain in a different question once I finish this.

To be honest I don't want also to do something which can later on haunt me. It is the first project we do in Revit. We started switch all the projects to Revit 2 months ago only we used to work with Allplan and Archicad but now everyone wants Revit

Re: Plumb wooden Rafters

ToanDN — Wed, 15 Jan 2020 23:39:18 GMT

Understood. I think using a mass contain of donuts to cut the rafters is the best approach.

Re: Plumb wooden Rafters

Marie.j03 — Wed, 15 Jan 2020 23:42:59 GMT

It is bagels we don't eat donuts 《: o p

Re: Plumb wooden Rafters

barthbradley — Thu, 16 Jan 2020 00:29:40 GMT

If you arrayed -- and did not ungroup after array -- then the revision ought to be painless. Just edit one instance of the group. No?

Re: Plumb wooden Rafters

Anonymous — Thu, 16 Jan 2020 07:16:22 GMT

Are there two types of roofs - circular and elliptical, or are they all different sizes?

I would consider creating a rafter family with instance parameters to control their length and slope (if this differs), with two legs (I'm assuming that each rafter has a corresponding opposite rafter). The Create each roof (with a blend for ellipses, or revolve for circular) and support as a family with the rafters nested in. Bring the families into the project.

Re: Plumb wooden Rafters

Marie.j03 — Thu, 16 Jan 2020 10:45:21 GMT

@Anonymous thank you for the reply...your prediction yesterday came true 《: o p

When you say slope is it same like same like option 1 above adding and angle parameter or is this something else?

Re: Plumb wooden Rafters

Anonymous — Thu, 16 Jan 2020 10:50:36 GMT

Yes, if the roof is an ellipse then the slopes will probably be different. Then you can add an angle parameter to the rafters.

Re: Plumb wooden Rafters

Marie.j03 — Thu, 16 Jan 2020 10:56:55 GMT

Hi,

I didn't work on this much yesterday because it was getting too late. But today I am and I have a question. I have been trying to make this mass in conceptual as you said but it wouldn't let and Revit prompts with an error Cannot create form from elements. Any idea what that might be? It did work when I sliced a 1/4 of the circle out but I'm not sure how to stretch it to cover the full circumference of the gazebo.

Re: Plumb wooden Rafters

RDAOU — Thu, 16 Jan 2020 11:04:09 GMT

You can use 2x Half Circles … do the first void with half and then do the second with another half 🙂 … personally I would construct it as per the images below. I will upload a screencast for you in a few

Re: Plumb wooden Rafters

Marie.j03 — Thu, 16 Jan 2020 11:12:10 GMT

@barthbradley hi,

I did say up that reference planes will not work! did you try to make the array then managed to cut with the plane?

On my pc it does not work as you described.. when cut 1 rafter I have to edit group and when I finish editing not all are cut just one! And when I do the same with the next rafter and finish editing the first rafter is uncut!

Re: Plumb wooden Rafters

RDAOU — Thu, 16 Jan 2020 11:44:55 GMT

You are not missing out on anything, what he stated doesn't work in your case.

Anyhow, check out the screencast below...as said earlier, that' my pref. you can still do that with 2x 1/2 circles

Re: Plumb wooden Rafters

Marie.j03 — Thu, 16 Jan 2020 15:52:03 GMT

Thank you so much. This worked perfectly and was done quicker than expected. I will mark all the solutions but I would still like to know how to build what you and @Anonymous suggested with a rotation angle. I will try and see how this go and I hope you wont mind me asking again if I need some clarificatios

Re: Plumb wooden Rafters

Anonymous — Fri, 17 Jan 2020 09:39:10 GMT

Try this family. It has two rafters with a space for the central post. The length and height can be adjusted.

Re: Plumb wooden Rafters

orsgeorgerobinson844 — Tue, 25 Feb 2025 19:46:40 GMT

To adjust the rafters to a plumb cut without redoing the entire structure, there are a few steps you can follow to minimize time and effort. If you're working in a 3D environment like Revit, AutoCAD, or SketchUp, start by selecting all the rafters and grouping or filtering them for easy manipulation. You can then use the “align” or “rotate” function in the software to adjust the pitch of the rafters so they are perfectly vertical. It’s important to ensure the base of each rafter remains fixed, with only the overhanging end being adjusted. By applying the rotation or alignment change uniformly to all the rafters, you avoid having to make individual adjustments.

In case you are using parametric modeling, such as families in Revit, modifying the length of the rafter or adjusting the tilt parameter to make the ends plumb will allow you to update all identical rafters without disturbing their alignment, tags, or annotations. This method is efficient because the changes will propagate through all rafters automatically.

If you’re working with physical drawings or manual methods, the process is a bit more hands-on. Start by identifying a plumb line. Draw a vertical line from the outer edge of each rafter down to where it would intersect the ground or the rafter's base. Manually adjust the overhanging end of each rafter to match this plumb line. You’ll also need to update the annotations or tags to reflect the change, ensuring the base of the rafters remains fixed in place.