Modeling
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Roof ridge join problem

Anonymous
Not applicable
When I create a polyroof over a set of walls the ridge lines don't actually join along the main ridge and two hips, effectively dividing the roof in half with about a 0.05mm gap! This is normally un-noticed in plans and elevations and is near impossible to measure but when I edit the roof to make a Dutch gable and trim a wall object to the roof for the gable infill using SEO, there is a narrow strip of wall poking up through the gap! I have to then zoom right in and shift the nodes of the roof so they meet and it is fixed.

Am I doing something wrong in creating the roof or is this a bug?

All construction grids etc are square and all walls have been placed square, then the roof is placed over the walls using the Magic Wand, SO WHERE IS THE "OUT OF SQUARE-NESS" COMING FROM??

Roof Join Problem.JPG
14 REPLIES 14
Ctrl-click.

In 3D, Select the roof with the highest ridge - press Ctrl and then right click on the low ridge.

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Anonymous
Not applicable
Thankyou
Steve wrote:
Ctrl-click.

In 3D, Select the roof with the highest ridge - press Ctrl and then right click on the low ridge.
For some reason, after much trying, this actually did fix the problem this time! I have searched this forum before and come up with this fix but it has never worked. What took the time was trying to get the select tool to select either edge while zoomed in (so close together!) and then trying to figure out which was the higher edge to get the lower to meet! See attached drawings for more problem detail.

This is a fix but can anyone explain why the program can't make a simple roof properly?
Does anyone else have this problem?
Roof Join Problem 2.JPG
Anonymous
Not applicable
I noticed elsewhere here that you can't attach more than one image...
Section 1.jpg
Anonymous
Not applicable
...
Anonymous
Not applicable
Notice the zoom on these. It is very hard to work out what is wrong, why it won't work. In the case of the Ctrl-Click tool, it is hard to see which edge is highest!
Anonymous
Not applicable
Section view at the ridge.
Section 2.jpg
Anonymous
Not applicable
Ridge section detail showing small gap.
Karl Ottenstein
Moderator
It is very often easiest to join the roof edges if you pull them back first, so that each edge is very clearly visible. THEN, select (click) one roof plane and ctrl-click the edge of the roof that you want to join to. Then do vice versa.

In particular, if you are joining a shed or gable dormer to the parent roof, this seems to be the most foolproof and fastest way to do so to me. (Note that the ctrl-click join process will not cause an over-extended roof edge to pull back... so you must be sure that the edges are a fair distance from where you expect the joint to be.)

Work in 3D and rotate through the model. Hidden line mode (internal engine) or wireframe can sometimes be helpful. Attached image shows pet palette in 3D to adjust the roof edge prior to the ctrl-click operation.

There may be a better way of course...

Karl
roof join.gif
One of the forum moderators
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Ben Odonnell
Contributor
Colin wrote:
Section view at the ridge.
I think you may have found a consistency problem. If you have a look at the image I have attached, you will see that you can choose to have all of the joins, edges vertical.

I know that when you create a polyroof you also get the opportunity to have vertical joins, edges. It seems to work but you don't get nice clean joins at your ridges, you need to CRTL click the ridge to get a clean join.

This to me, seems irrational. It should work the same regaless of the geometry method.

When you created your polyroof did you use the magicwand or did you draw out the footprint of the roof by following the wall line?

Cheers.
Ben
Ben O'Donnell
Architect and CTO at BIMobject®
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