Help with auto roof plane


BeeoHat
 Share

Go to solution Solved by Rich_Winsor,

Recommended Posts

I'm modelling my son's home for a reno. The attached photo shows the roof planes of the deck over the kitchen alcove. My other plan image shows the auto roof generation. I've tried all kinds of manual roof plane manipulation, with no success. It seems to me I would need a gable wall on the house side to generate the desired roof, but of course there's no wall there.

 

Is there some simple setting I'm missing, or does this require some fancy roof plane manipulation?? ^_^

post-567-0-97248200-1398955289_thumb.jpg

post-567-0-82558900-1398955371_thumb.jpg

Link to comment
Share on other sites

If there is no wall I'd have to do it manually. I would have used a railing wall ( post to beam) so you could have a wall to change if you wanted to do it that way. Post the plan so we could see exactly what's going on there.

Link to comment
Share on other sites

If that is a level ridge coming out from the house, centered on the bay feature bump within the porch, there must be a cricket in there that we cannot see.

 

There is snow and shadow in the way.

 

Your Chief model only shows us what you tried to do to duplicate it.  We need better photos of the as-built.  Are you able to better examine all those elements of the porch roof, and measure pitch of each?

 

Is there something like this going on?

post-55-0-86591800-1398960305_thumb.png

Link to comment
Share on other sites

Gene, I have no better photos at the moment, but yes, that is a level ridge coming out, exactly as you said. It is that ridge I'm trying to emulate. Sorry about the picture quality. There is in fact two crickets there, one right under that snow patch, which has the diverter at the bottom. And another matching cricket on the opposing side (not in view).

 

Hope this helps.

Link to comment
Share on other sites

Gene, sorry I missed the diagram in your previous post. In your diagram, there are two crickets showing, on either side of that triangular roof plane.  In the subject house, there is only one cricket on each side of the ridge line. This cricket runs straight down from the wall to the gutter. There is no additional triangular roof plane as shown in your diagram.

Link to comment
Share on other sites

That could be a roof that can not be built easily in CA.

 

 I like Gene's solution,  but I do not ;think that is the way it is and the op said there were not the crickets that Gene showed.  

 

I like Jim's guess more......  

 

If the op would sketch the roof  plan,  I am sure somebody can figure it out.  The op needs to show a roof plan of hips,  valleys and ridge.  

 

if it is the way I think it is, (without crickets and a horizontal ridge) the rafters of the angle roof plane do not have a consistent pitch.  Tough to build the in CA.

Link to comment
Share on other sites

No, this is not a hip. There are two hips which come off the ridge, only one of which is evident in this photo. These hips form one plane. I've drawn up an illustration in Sketchup to give you a better idea. Image attached. Does this help?

post-567-0-70991600-1398968507_thumb.jpg

Link to comment
Share on other sites

No, this is not a hip. There are two hips which come off the ridge, only one of which is evident in this photo. These hips form one plane. I've drawn up an illustration in Sketchup to give you a better idea. Image attached. Does this help?

Yep,  that is what I thought it might be.  It is not what Gene said ( a solution but not the best),  it is not    Jim's solution,  (I think Jim's is the best),  but it was my solution,  the toughest to build.

 

You must think about how that roof plane is built.  

-Note that the fascia is parallel (horizontal) to the ground.

-Note that the ridge is parallel (horizontal) to the ground.

-Now imagine each one of those rafters that will create the roof plane.  The top and the bottom of each rafter is the same height above the ground,  yet each rafter is longer than the next.  Therefore,  each rafter has a different slope.  

 

Very tough to build a ROOF PLANE with CA to meet this criteria.  Glenn could probably do it.  The roof plane would probably need to be on an angle.

Link to comment
Share on other sites

My apologies to Jim. On closer inspection,  Jim is quite right is suggesting the extra hips. When I think about it, it HAS to be a separate roof plane!! A single plane cannot bend around that hip!!. An updated image is attached. I still need help with it, though.

post-567-0-90536200-1398972110_thumb.jpg

Link to comment
Share on other sites

Not automatically.  You will need to learn how to manually draw roofs.  It is a very worthwhile exercise.  Chief gives you total control.

 

This one has the pitch at 4:12, except for the ones that make the level ridge.

post-55-0-60302300-1398976779_thumb.png

Link to comment
Share on other sites

  • Solution

Close but no cigar.  Your hips should be at angles of deck.

 

Not even a Tiparillo? :)  Hey, I was just whipping up a concept

sketch based on the roof plane configuration BeeoHat posted

from SletchUp. I get what you are doing by refining the concept

and positioning the hip rafters over appropriate structural members.

However, I am not sold on the idea that the "doglegs" in the hips

and valleys in your plan roof are present in the "as built" structure.

I could be wrong as the only pic is murky at best but my guess is

that all the hips and valleys are straight from ridges to eaves as

in the OP's sketch. That's why I just sort of split the difference

as to where the hip rafters would cross the upper railing beams

and let the roof overhangs fall where they may. No big deal,

I enjoyed the vids.

Link to comment
Share on other sites

BeeoHat ,what you are calling a cricketin your Sketchup Posts , (no#2 is correct by the look of the photo) is just a valley, a Cricket is a small roof that usually sits behind Roof Penetrations such as chimneys to divert water around it. a quick google got this to show you :

http://www.mcgarryandmadsen.com/inspection/Blog/Entries/2013/2/25_What_is_a_roof_cricket.html

and ps the small white "hip" in the photo,someone mentioned ,at the gutter ,below the snow is a water diverter because of the valley I believe.

Your No#2 Sketchup image looks right to me Beeohat without better photos (ie 5 planes not 7)... ,it would be more typical if the ridge hit the wall at the porch roof line but the photo does suggest what you have "sketched"

M.

Link to comment
Share on other sites

I'm modelling my son's home for a reno. The attached photo shows the roof planes of the deck over the kitchen alcove. My other plan image shows the auto roof generation. I've tried all kinds of manual roof plane manipulation, with no success. It seems to me I would need a gable wall on the house side to generate the desired roof, but of course there's no wall there.

 

Is there some simple setting I'm missing, or does this require some fancy roof plane manipulation?? ^_^

Break the roof and add the other planes manually. 

Link to comment
Share on other sites

Crickets are also used for the situation shown here.  I x-scrubbed away the roof above and some soffit so you can see it.  Any little roof doodle that is done, usually atop a roof already sheathed, to get the water away and not cause problems, is a cricket.

 

Wonder where the term originated.

post-55-0-16339300-1399055075_thumb.png

Link to comment
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
 Share