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roof framing #2 - purlins


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is it because i'm in

the southern hemisphere?

the roof framing tool puts things

together in a very weird way.

the purlins are correctly shown

underneath the roof surface, but

the rafters, hips, ties etc are

all ABOVE the purlins...

this wouldn't be too bad if you could

just lift the purlins + roof above the

rafters, but then the rafters are too

"long" for the roof, which then involves

a rafter editing festival.

do they really make roofs this way

in the northern hemisphere?

or am i totally misusing the tool?

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Gideon, in this instance purlin = under purlin.

In stick roofing the purlins are usually called (roof) battens which the Roof Framer doesn't model.

We use a similar convention here in Australia:

- Where the members are spanning a long distance between widely spaced rafters (and are therefore large) they are called purlins.

- Where the members are spanning short distances between closely spaced rafters (and are therefore small) they are called battens.

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Regretfully, the roof framing command took a dive with v12. You might also have learned that it sometimes doesn't pitch the rafters correctly. Used to work pretty close to real-world, now it's not very close. This has been discussed several times here and I believe entered as a wish-list item if not a bug.

The work-around is just that: work around or have an editing festival (what a metaphor!) One shortcut during that festival is to pick a view that facilitates selecting all the rafters at once (and any other members "out-of-plane") and move them all together.

We use the Framing Member tool on a daily basis and would possibly use the Roof Framing command more IF it worked properly.

Sorry I don't have better news!

Good luck,

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Travis - The rafter pitch problem was rectified in VW 12.5.1.

Are you still having the problem?

If so, please send a file and I'll submit it as a quality report.

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Katie,

You're right. I'd grown so accustomed to simply drawing all my roof components, that I hadn't run the Frame Roof command since updating. Thanks for noting this.

BTW, if the Framing Member Tool was ever to come up for review, I'd love to offer some input.

Best,

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Same her in RSA Mike

Especially in the steel structural side = Purlines

Residential = more frequently it is battens.

Roof framing tool is actually a waste here - want the battens ontop and where is the trusses ?

Why insert a half finished tool - rather leave it out. If you do something please do it very well or leave it.

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There is a real need to add a genuine truss capability to Architect. The lighting truss tool in Spotlight demonstrates that the programming capability exists within NNA. I can't understand why it hasn't been used to creating a useable floor and roof truss capability in Architect.

The other big omission in Architect is portal frames.

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We are building brick and mortar house here but we do the same roofing structures - for the people who does framing - VW must be a waste too. Any cheap skate program can do what have to be done any way manually.

Think it is a disgrace - NNA should not even mention this "capability". Will never be able to understand that they do not, as it seems, feel ashamed of themselves. They drop their users trust in the deep side.

Again - do it right or leave it and tell your users straight up that you do not have the capabilities to it properly. Otherwise straighten up in getting the standard as it should be.

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The way the tool works at the moment reflects the way we build timber roofs here in the UK, in that the purlins go under the rafters. However, if I were designing a steel portal framed building (a portal frame tool would be nice) then the purlins would go above the rafter. So we could do with a setting which allows us to specify the purlin location.

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