Roof framing plan from hell

[GeorgeCF99]

I am currently using AutoCAD 2009 and have a plan that either needs someone who knows what they're doing when it comes to designing a roof framing plan or someone who knows how to rework the roof design into a more buildable structure. The current roof plan just has one section where I can't make sense of how it would be constructed (lots of hips, valleys, and slope changes).

I will be building under NC code, and need help bad!

[Dadgad]

Welcome to the forum.

Sorry to hear it, are you able to post the drawing?

Barring that it will be hard to get any help.

Strip out any nonessentials or proprietary content.

I am not a roofer, but a carpenter of many years, lots of smart

forum members, don't despair, somebody will

be able to help you figure it out.

Above all, a good roof.

[GeorgeCF99]

Dadgad, Thanks for the encouragement. Here's a snap shot of the section where it's a problem. First, the 2:12 slope will pose problems. Second, it's way too complicated...

[sevdo2000]

It's a very strange roof. If it has to be made, I see many problems and the least of them is flooding under it. The minimum of roof lines, guarantee minimum problems! It's look like a roof generate from some 3D proggram (REVIT or Architecture), without any man made correction.

[Dadgad]

Hellacious is I believe the term that would best describe this.

Hard to believe that it needs to be this difficult.

 

Where's Taylor when we need him?

 

It would be a lot easier to understand as a .dwg than just a screenshot.

Difficult without getting information which would clarify elevations and such, and an overview of the roof as a whole.

 

I am guessing that it has not been modeled in 3D yet?

I find myself wondering what Bucky Fuller would do in a case like this?

The answer? Something a lot easier than this.

[GeorgeCF99]

I'll try to get a the .dwg line drawing loaded tomorrow without any proprietary info, and nope, this hasn't been modeled in 3D. I have somewhat of a solution, but am not gifted enough in the ways of CAD to get it right, especially with absolute slopes.

[James_SMI]

Dadgad, Thanks for the encouragement. Here's a snap shot of the section where it's a problem. First, the 2:12 slope will pose problems. Second, it's way too complicated...

That doesn't look buildable if you ask me. I would start with the walls and then start adding roof lines.

[Dana W]

2:12 slopes are against code in most US areas without flat roof rainwater & snow load management. A lot of counties in the northern states won't even let you build conventional truss/rafter roofs flatter than 5:12.

 

To figure this one out in 2D would make me want to set up my drawing so I could use orthographic projection just as if I were using paper and pencil. There obviously are many changes in exterior wall height that MUST be accounted for.

 

Just looking at it makes me want to chase the architect round the parking lot with a lit torch and pitchfork.

 

Turn some of the wall jogs into covered areas and reduce the number of separate planes in that roof.

 

One time, I had a fairly complicated roof to figure out the framing for. Turns out, if built, two of the smaller roof sections would have ended up fully enclosed in the attic. The longer slopes just completely covered them up. The archi-monster (you know who you are) had not drawn the roof nor wall heights to scale (not even close) in the conceptual phase.

[James_SMI]

You might get away with a 3:12 using ice guard or something, hard to predict what the building department might work around. By NC code you mean North Carolina? I lived there for 20 years, no telling what you'll run into depending on where it's at there.

 

In the absence of a 3D program I would make a scale model using file folder cardboard, crude but easy. Cut peices to size and leave tabs to glue together. You don't mention whether you are using part or all engineered rafters or it's just pure stick frame. A lot of times framers figure out how to build something on the fly, since architects always know what they are doing (cough). Even with over 20 years in construction including building new custom homes, I wouldn't tackle that without some way of seeing it 3D, way too much going on.

[GeorgeCF99]

I haven't had a chance to go to the office and get the CAD file, but I did get to build a scale model. Now, the model doesn't have extremely accurate slopes, but they're close enough to get the idea. The problem is, I don't have the knowledge or skill to create this complicated roof in 3D. Basically I made it work with this section only having 2 hips, but I do t know what slope I would need on each to have them all come together.

With all that said, North Carolina code has a rated snow load factor of 15 lbs but we try to go with 20 lbs. If I were to actually attempt this current plan, I would use a standing seam roof on the 2:12 portion. The roof will be stick built, but as a GC and my brother as an experienced structural engineer, I'm a bit puzzled on where to start.

[James_SMI]

I haven't had a chance to go to the office and get the CAD file, but I did get to build a scale model. Now, the model doesn't have extremely accurate slopes, but they're close enough to get the idea. The problem is, I don't have the knowledge or skill to create this complicated roof in 3D. Basically I made it work with this section only having 2 hips, but I do t know what slope I would need on each to have them all come together.

With all that said, North Carolina code has a rated snow load factor of 15 lbs but we try to go with 20 lbs. If I were to actually attempt this current plan, I would use a standing seam roof on the 2:12 portion. The roof will be stick built, but as a GC and my brother as an experienced structural engineer, I'm a bit puzzled on where to start.

That things so bad even Bob Villa would be scratching his head If you were stick framing it you would start with you ridge beams, figuring out how to hold those in place. Then you would put your valleys in, then rafters right? So it's a matter of taking each step at a time.

[samchums26]

it will not be even possible to build that roof plan in 3d. it is not complicated, it's just wrong.

[eldon]

Until the OP posts a drawing or a legible screen shot, one cannot say that the roof is impossible to build.

 

Impracticable and unconventional, but with a bit of devious thinking, it might be possible.

[pendean]

Do you have Elevations that go with that plan?I can't imagine anyone with an ounce of sense drawing a roof plan that detailed without elevations: they might reveal the "intent" and make corrections or redesign easier.

And a walls floor plan too please.

[Currahee]

Hellacious is I believe the term that would best describe this.

Hard to believe that it needs to be this difficult.

 

Where's Taylor when we need him?

 

It would be a lot easier to understand as a .dwg than just a screenshot.

Difficult without getting information which would clarify elevations and such, and an overview of the roof as a whole.

 

I am guessing that it has not been modeled in 3D yet?

I find myself wondering what Bucky Fuller would do in a case like this?

The answer? Something a lot easier than this.

 

I know...I just read it...

 

Let me read everyones post then I will post if I am still needed:D

[Currahee]

A 10 or 12:12 roof is probably what they wanted...no way a 2:12....hell that's flat. Get me the floor dimensions and the overhang and I will fix it for you.