Looking for any tips or techniques on framing a bay roof read all the articles online but looking for other options than drawingit out on plywood being as roof is too large any input would be appreciated
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Greetings crazyfalker, snork*
As a first time poster Welcome to Breaktime.
This post, in response to your question, will bump the thread through the 'recent discussion' listing again which will increase it's viewing.
Perhaps it will catch someone's attention that can help you with advice.
Cheers
every court needs a jester
Thanks for the bump as a 1st timer any help is appreciated will definitely have to work on wording/explaining myself with my discussions again thanks for the help.
Is it a Bay Roof off the back of a wall or is it a bay roof that needs to be framed into another roof with true valleys.Here are a couple drawings.Joe Carola
It is a bay roof that is framed into a wall I was able to accomplish what your drawing is showing with the old school method of stringlines and running my sub fascia first. I cut my commonsand ran my ledger on the wall wild until I had determined where the bastard hip would land. My confusion on these roofs is how to determine that point without having to figure it by trial and error. Also shouldn't the hip against the wall also be at a 5/13 pitch rather than a 5/17 and if not is that how you determine the point where the bastard hip goes? Any more advice or input would be appreciated, thanks for the visual aids and response.
Edited 3/19/2007 12:04 am ET by crazyfalker
It is a 5/17 because it is a hip on a 90 deg. corner. But you only see it in plan as a hip on a 45 deg. corner.
try sketching it out at one of the corners by bringing the 45 deg wall to the hip intersection then creating a 90 there and you will see what is happening and why it is a 5/17 hip not a 5/13 or octagon hip.
thanks for the replys appreciate any insight or advice from skilled tradesman look forward to more advice in the future
Another way is to come in the same distance from the outside corner of the bay on each side the same length as the short side walls.The bay roof that I drew was a 2' projection with a 3' front wall giving you a 2' 9-15/16" side walls and a total width of 7'.2'9-15/16 x 2= 5'7-7/8"7' - 5'7-7/8" = 1'4-1/8"Joe Carola
With a construction master would it work, if by now understanding that the hips against the wall are true 5/17 hips, would you not be able to get the bastard hip point by just entering your rise and known pitch and hitting the hip/valley function to give you the length of the 5/17 hip which would give you the point where the ledger would stop. Not sure if that is correct, just trying to simplify it as much as possible.
>> With a construction master would it work, if by now understanding that the hips against the wall are true 5/17 hips, would you not be able to get the bastard hip point by just entering your rise and known pitch and hitting the hip/valley function to give you the length of the 5/17 hip which would give you the point where the ledger would stop. <<Sorry for not responding to you sooner.Yes you can get the hip point by doing that if you wanted too. As you know that the hip point is the same distance in from the corner as the width of the side walls are.My example with a 5/12 pitch and a 2' projection, you can also just punch in 5/12 pitch with a 2' run and hit the [Hip/Val] button and that's your hip length.Don't forget that once you set the two hips in and ridge in you loose an 1-1/2" on the common and bastard hip run. The H.A.P. cut on the hip where it hits the plate on the 45° wall coming in 1-1/2" has to be the same size as the common H.A.P. cut so the tops plane in.You'll see in the drawing that I just modified where you have the 2'x 2'triangle and the hip diagonal length for the run in plan view takes place to the center point of the bastard hip.Joe Carola
Hi Joe,
I read your post regarding the framing of a roof over a bay off a wall. (Ragnar refered me to it) THANK YOU! It has helped me immensely. I have a few questions. Would it make a difference in layout if the outside corners were 34 degrees instead of 45? Mine are. The house is one hundred years old and the builders seemed to build on a whim, without much consistency. Also how difficult is the learning curve on the construction master? Are the instructions fairly detailed? Again, your generous gift of expertise is greatly appreciated.
>> Would it make a difference in layout if the outside corners were 34 degrees instead of 45? << Glad that I could help so far.It wouldn't make a difference, you would still come in the same distance as the side wall from the point where the side wall hits the house. That will be the center of the hip.Are you sure it's running at 34°? What is the exact measurements of the projection and the length of the side wall?Let's say that your projection is 24" out from the from the existing framing, theat means that the side wall should measure, 3'6-15/16".As far as the Construction Master is concerned, it's really how much you know as far as cutting rafters and how you view them and what you put into the calculator. When you view things in plan view it helps put everything in perspective as far as I'm concerned.If you tell me what the projection and the length of the side wall is,, I'll be able to tell you if your wall is really 34°. What size overhang will you have? Also what size is the front wall and do you have the total length of the wall and are both side walls the same length?Joe Carola
Edited 3/25/2007 8:41 am ET by Framer
Hey Joe,
I've checked the angles of the bay with a starret miter gauge and I get 34 degrees. The bay is 25" deep, inside the house against the sheetrock the outer wall corner to corner is 54". The left angled wall is 41 1/8" and the right is 41 1/4". The measurement corner to corner where the bay begins is ten feet. The soffit will be 6-8 inches wide. I haven't had time to draw it out on plywood yet as some suggested but I don't see why your method wouldn't work with the 34 degree corners. I'm going to try drawing it tomorrow night as I would like to demo the disaster that is up there now and frame it correctly this weekend. Any additional advice you feel might be helpful would be greatly appreciated.
>> Also shouldn't the hip against the wall also be at a 5/13 pitch rather than a 5/17 and if not is that how you determine the point where the bastard hip goes? <<No, it's 5/17 because it's running at 45° from the short side wall exactly like a regular hip roof. Just look at the picture and look at the side marked 5/12, that's the common rafter and the hip runs at 45°. The Bastard hip runs at 67.5° exactly like an Octagon Roof with a 5/13 pitch. To get where those points are can be done many ways that are easy once you visualize it it in plan view.Are you using a Construction Master Calculator or Scientific Calculator or Framing Square? What way would you like to know and feel comfortable with?Joe Carola
Using a construction master calculator after using and rationalizing yours and dovetails feedback it makes much more sense thanks a million for the tips look forward to hearing from you in the future
p.s feel free to give your const. master method as I am sure I will run into this situation again
If you have the Construction Master Trig, you can do this to figure out how far to come in off each end of the front wall.24/67.5 [Tan] = 9-15/16"Joe Carola
In my drawing the front wall for example is 3' and the bay projection is 2'.One way using the Construction Master would be like this in plan view and you will see the small triangle it creates:24 [Inch] [Rise]67.5 [Pitch][Diagonal] = 2'2"[Run] = 9-15/16"That 9-15/16" is what you would come in and take off each side of the front 3' wall and what's left over will be your center points of where the hips would be up against the wall.9-15/15 x 2= 19-7/8"3' - 19-7/8" = 1'4-1/8"Or just come in from the front 3' wall square and make a 3' mark on the wall and come in 9-15/16" from each side.Here's the drawing that I changed a little. Hope it's clear.Joe Carola
Edited 3/19/2007 11:46 pm ET by Framer
Yep, a lot of experienced folk here on BT.
Glad to have you around. View Image
every court needs a jester
Done it to scale several times. Pick a scale that fits the plywood sheet you are using for the drawing.
I use the 12th. scale on the framing square if need be.
Carefully done it will give you everything you need.
I wanted to do something a little different on my house so I framed a shed over my bay window. Framing the sidewalls under the eaves was a little difficult but the overall curb appeal was good.
Joe seems to have you on the right track with the math but I wanted to add a little something here.
A couple of tips to help skip some of the math. Sometimes I find it easier to layout just a section of the roof on ply and get all my units right from the layout. For me, it is sometimes faster than working through all the calcs on a small roof like your bay.
If you pull an equal distance from the 45 degree corner in both directions along the plate and make a mark. Then swing an arc from that mark toward the hip travel area from both sides. Find where the two arcs intersect. Connect from the 45 degree corner through that mark and you will find the end of your ridge and this line is also your hip travel. Then you can use rise/run to find your pitch and rafter length.
Its important to remember that most of these bays are just segments of an Octagon. Getting my head around that made these things go from a PIA to a walk in the park.
Brian,Read post #13
http://forums.taunton.com/tp-breaktime/messages?msg=87201.13The point where the hip hits the wall is the same length coming in level in plan view as the the 45° side walls top plate measuring in from the point of the side wall where it hit's the house.Just measure in that same distance and make a plumb line up and that's the center of your hip and whatever pitch you use your rise will hit there. Check out the drawing in that post. You'll see the 2' 9-15/16" top plate and you'll see the 2' 9-15/16" measurement coming in from the 45° corner.Joe Carola
Edited 3/24/2007 5:32 pm ET by Framer
Wow, I never knew that before Joe. You just saved me even more time on these things. I don't know if I ever would have picked up on that if you didn't point it out. Where do I send the check to? :)View Image
>> Wow, I never knew that before Joe. You just saved me even more time on these things. I don't know if I ever would have picked up on that if you didn't point it out. Where do I send the check to? <<Brian,You would've picked it up once you seen it drawn on a deck in plan view.No checks necessary. Maybe some day I take ride up by you and you can give my son a ride on your forklift.Joe Carola
You know, I bet I've snapped out a couple dozen bays in plan view lately and still never picked up on that. Recently I've been doing a ton of snapping out in plan view because I keep running into bastard octogon rooms for some reason. I enjoy cutting them and love watching them go together, but every little short cut helps.
And don't tell anyone, but I'd let Joey drive the forklift if he wanted. :) Ha Ha Ha! (I'm sure that'll send someone through the roof here!)View Image
>>You know, I bet I've snapped out a couple dozen bays in plan view lately and still never picked up on that.<<Brian,Next time measure the length coming in from the outside corner and you'll see. I used to set my speedsquare at 22.5° on the outside corner on the deck and then just continue the line in until it hits the wall and that would be the center of the hip. Or you can just punch in 22.5 [Pitch] and 24" [Run] and hit [Rise] and get 9-15/16" and that how far you come in from each corner of the front wall and transfer that mark at the house and that's your hip center. There are many ways to do it.>> And don't tell anyone, but I'd let Joey drive the forklift if he wanted. :) Ha Ha Ha! (I'm sure that'll send someone through the roof here!)<<Yes, we would be in big trouble.Joe Carola