I have searched the archives on the subject of how to make the facia match up on irregular hip roof pitches. Either I am not searching right or the info I want is not there. What is the best method of doing this? The formula we have been using is to take the difference between the rises and make the heel height of the lower pitch that much less. This allows the overhang to be the same and the facia to match up.
Aiso, how do you guys handle irregular hips without getting into a guessing game. For example, we just did a 1412 meets a 1012. How do you determine what the heel height ought to be and much off center it needs to swing?
James Hart
Replies
One way of doing this that is relatively easy is to draw a full scale model of the eave area of your roof, along with the TOW area. Use your square to get the exact slope. Fill in the details. Then superimpose another roof drawing of a different slope on that one. It will be apparent that the roof with the steepest pitch determines how far the soffit area extends out from the wall, say one foot, for example. The lower pitch roof will protrude further out from the wall. The scale drawing will show exactly how much further.
If the lower pitched roof goes out an aesthetically unacceptable distance, you can build up the top plate or the wall height enough to meet your requirements. When everything is is place, you should not be able to see any difference from below. You get the benefit of a higher ceiling in the lower-pitched room, with just a little extra construction cost.
I see what you are saying and I have done the layout on paper before. The problem comes when we cannot have a ceiling height difference.
When the plates have to be the same height then there has to be some juggling of the HAPs between the two pitches.
If I make the steeper rise the maximum heel height then that leaves me room to cut more out of the lesser rise birdmouth.
I think the architect needs to make his drawings accommodate the difference in plate heights. That is probably my biggest problem. I am trying to make something work that was not drawn right.
James Hart
Having the ceiling height the same in both areas is a constraint you did not mention initially; however, it does not change anything. You start out with the choice, once you have figured out your approach, of whether to have the overhang different or matching. If it is ok to have different overhangs, you can leave the wall heights the same. If the overhang must be the same aroung the entire house, you will have to raise the wall heights.
Paper drawings are fine for figuring this stuff out; however, a scale drawing on the subfloor may give a better understanding.
If you have to raise the height of the walls in one section of the house, and the ceiling heights must be the same height, you are committed to building a ceiling below the wall height. This is not much different from a coffered ceiling. It may be a couple hundred bucks for additional lumber, and maybe two hours of work. I don't think this is much of a brain teaser. Start with your requirements and constraints. Meet them. Then adjust the result to the needs of your customer.Les Barrett Quality Construction
"If you have to raise the height of the walls in one section of the house, and the ceiling heights must be the same height, you are committed to building a ceiling below the wall height."Les,I frame the walls at the same height and put the ceiling beams on top of the walls at the same height what I do different then what I think your saying is that I will add the plate height difference in between the ceiling beams. If the plate height difference on the steep side to keep the overhangs the same is 3" I will cut 2 blocks and nail them into the top plate in between the ceiling beams and then nail the blocks to the ceiling beams and then sit my rafters on top of the blocks.This way there's no additional lumber and added time to create a new ceiling.Joe Carola
Joe,
That is a very good point, and exactly what I would actually do. I was addressing the broader case where that would not be architecturally feasible due to restrictions on having the soffit look the same on all exterior walls, the ceiling height the same, and the roof pitch radically different in two roof sections. Otherwise, my first suggestion would be to just make the overhang a bit wider where necessary as it is the least likely element to be noticed for a minor difference, say from 12" to 16". The next solution would be to do as you suggested.Les Barrett Quality Construction
James,
Happy Thanksgiving. There's a lot of answers to your questions but first off how do you figure your rafters do you use a Scientific Calculator, Framing Square, Construction Master or strictly the Rafterman?
There's a lot of ways to figure theses roofs but which way do you do it and I can give you answers. The Construction Master Calculator is the fastest for most of these "Bastard Hips". The plate height difference, H.A.P. cut/Heel Height and many other things are easily figured with this calculator.
Joe, my daddy's birthday is on Thankgiving and the whole family went to his house yesterday for dinner. Had a great time.
I use the Swanson Blue book most of the time. I recently downloaded a trial version of Rafterman because the roof we were on was a 1412 and the blue book does not go up that far for the span we had.
I have never bought a calculater but have looked at them many times. Is that something I should really get?
James Hart
"I have never bought a calculater but have looked at them many times. Is that something I should really get?"It's up to you. I think it's worth it. It will give you all the information you need for Irregular Roofs once you know what to put into it. It's definitely the fastest way to figure any angle on a roof Irregular or Regular for example your 10/12 and 14/12 combination without any ridge deduction with a 16' run which includes a 12" overhang on the 10/12 side to keep the same overhangs and flush the Fascia's.10 [Inch] [Pitch]16 [Feet] [Run]Press [Diag] Returns - 20'9-15/16" (10/12 Common Rafter Length)Press [Rise] Returns - 13'4" (Rise)Press [M+] (for Memory to store the Rise Measurement)14 [Inch] [Conv] [Hip/Val] Returns - 23'9-1/6" (Hip Length)Press [Hip/Val] Returns - 34.14° (Hip Plumbcut Angle)Press [Hip/Val] Returns - 55.86° (Hip Level Cut Angle)Press [Hip/Val] Returns - 35.54° (Angle Hip Runs 14/12 side & Cheek Cut)Press [Hip/Val] Returns - 54.46° (Angle Hip runs 10/12 side & Cheek Cut)Press [Rcl][Rcl] (for recalling Rise Measurement) Returns - 13'4"Press [=] [Rise] Returns - 13'4"14 [Inch] [Pitch]Press [Run] Returns - 11'5-1/8" (14/12 Common Run)Press [Diag] Returns - 17'6-3/4" (14/12 Common Length)35.54 [Pitch]12 [Inch] [Rise]Press [Run] Returns - 16-13/16"16-13/16" - 12" = 4-13/16" (Hip Offset Towards the 14/12 side)With a 10/12 and 14/12 combination you already know that you would subtract the 10 from the 14 and get 4" which would be your plate height difference on the 14/12 side keeping the H.A.P cut/Heel cut but I wouldn't add 4" . I would just add 3" two top plates and add 1" to the H.A.P. cut on the 14/12 side. So if you H.A.P cut on the 10/12 Common is 6" I would make the H.A.P. cut on the 14/12 side 7".If you have a 16" overhang you can do this.14 - 10 = 4
4 x 16 = 64
64/12 = 5.33" or 5-5/16" (Plate Height Difference)Using the Construction Master.14 [Inch] [Pitch]
16 [Inch] [Run]
Press [Rise] Returns - 18-11/16"10 [Inch] [Pitch]
16 [Inch] [Run]
Press [Rise] Returns - 13-5/16" 18-11/16" - 13-5/16" = 5-3/8" (Plate Height Difference)This way takes to long but I'm just showing you how you can play around with the calculator to understand how it works.Joe Carola
OK. WELL NOW. I need to learn to use a calculator. This dog needs to learn some new tricks.
I can certainly see where using a calculator would make our work easier and faster. Is there one you especially like?
Again, thanks for the info and I hope I can ask more questions in the future.
James Hart
James,I use the Construction Master Pro Trig Plus 111. It's the best one because of the trig. It has all the functions of a Scientific Calculator you need plus all the other functions for Irregular Pitched Roofs. It definitely makes things a lot faster to figure out for these types of roofs once you know what to put in them.Why not try to get the answers faster and save time when cutting a roof. The Roof Framers Bible has a lot of information about Irregular Pitched Roofs but it doesn't tell you when you have for example a 6-5/8/12 pitch roof with an 8-1/4/12 pitch roof combination. Now that I've figured out what to put into this calculator those two pitch combinations are easy. You will see. Ask all the questions you want and if I can answer them I will if not I will try to figure out a way.I would order this calculator if I were you it is money well spent.https://www.calculatorwarehouse.com/cgi-bin/shopper.exe?preadd=action&key=4075Joe Carola
Linking this thread to others. This is the kind of material FHB should be publishing. This is so cool. Think if this was coupled with resulting line drawings and images of the calculators being used.....
Joe, I bought the book "Roof Framing" and I must admit that I have to read the explanation several times before I can begin to understand what he is saying.
I have looked at the other book you mentioned and was gunshy about buying it but I'm going to go ahead and get it.
I'm sure the questions I'm asking have been discussed before but I'm new to the forum as far as posting and asking questions and searching the archives is sometimes helpful but sometimes confusing.
Thanks again for everyone's help. WE have 4 big houses coming up and I just might need some input.
James Hart
James,You can use just about any scientific type calculator to get the angles and lengths to frame roofs. The Construction Master Series are excellent though you really don’t need one. They will help you in the sense that you input information as units of feet and inches and the output is also in feet and inches. Using a $10.00 scientific calculator will provide the same information just in decimal form.Hacknhope,There have been guys putting up this type information on this site for about eight years (that’s how long I’ve been here) that I know of. At one point this place was cutting edge. . . .
Try http://www.easyrafters.com
I have been using a CM 4 and CM Pro for along time, but easyrafters will take the cake with its ease of use.
The biggest down fall is that you have to use it on a computer, so unless you want to be make fun of by bringing a laptop to work, then you have to bring the span home and plug it in.
Go try the demo.
All you have to do is type in the span and the pitches and it will tell you all the rest, including the H.A.P. and all of the jack lengths. Plus it automatically subtracts for the ridge and hips so the numbers are exact. Then you can print the info out and use it the next day.
I can do it on the CM but easyrafters saves alot of time.
Thanks Kyle. THat program must be like Rafterman. My son has a laptop and we thought about loading the program onto it. I like getting the printout at home.
Does easyrafter deal with mixed pitches?
YOur right. The computer program does make it fast and easy and we found that Rafterman was right on with the dimensions.
James Hart
Does easyrafter deal with mixed pitches?
If you mean Bastard Roofs then the answer is yes.
It will tell you the jacks on both sides, how far to offset the hip from the corner, how much higher the end wall has to be for the steeper rafters to sit on, and how much to drop the hip.
I checked the numbers and they where spot on. I using its cut list for the first time monday. I'll let you know how it goes, but I don't expect and problems.
I downloaded the 30 day trial version of easyrafter. Seems like a great tool.
My son has a laptop and if we like the program after 30 days we might put it on the laptop.
Thanks for the tip.
James Hart
Try http://www.josephfusco.org/phpbb/index.php as well for some roof framing advice. I've gotten more there (from Joe and Joe) than I would have anywhere else.
Also, copy down everything that Joe and Joe post because seeing both of their styles will help you understand the concepts better, and I highly recommend Joe Fusco's article in JLC. The graphics are excellent.
Joe,
I went to the calculater site and found the one you were talking about for a good price. Thanks.
Another question I have is this: Let's say that you have a main roof that is a 1010. You have 3 gable roofs on the front coming into the main roof at 90 degrees. On the back you have a large hip coming into the main roof. There is no place to set a main roof common in order to set the ridge. It is difficult to ascertain the span of the main roof because it is broken up by valleys. How do you determine where the main ridge goes?
There have been times when I have had to pull several different strings from different directions in order to arrive at a point to place a ridge. Does that sound crazy?
I don't know if I have made myself clear. Sometimes I get my scaled ruler out and take my best shot. So far I've been fortunate. I think there must be a better way.
James Hart
James,Is there any way you can draw the roof that your talking about. I don't really understand what your saying. You have 3 gables that face the front of the house with a 10/12 main roof pitch?Joe Carola
You have forced me to confess. I don't know how or where to go on my computer to do the drawings. I have seen the ones who send out but have no idea how you do that.
Is it a software program? Sorry, I wish I could draw that roof I'm talking about. It's a dandy.
James Hart
We have already started framing the roof on this house and the best I can do is send you a picture. We finally figured it out but we had to set some temporary commons in order to set the main ridge correctly. Of course that meant setting some temporary beams and rafter plates that had to be removed later. All that takes time and time is money.
James Hart
James,I use paint for all the drawings that I do. I'm not sure but I think most computers already have it. Try this.Click on Start.Click on Programs.Click on Accessories.Click on Paint."We finally figured it out but we had to set some temporary commons in order to set the main ridge correctly. Of course that meant setting some temporary beams and rafter plates that had to be removed later."James, There's nothing wrong with doing that at all I do it all the time when you have a big house with 35' - 40' hips or valleys setting up a temporary King Common is a great thing to do because it helps you set everything in place and holds everything up. It doesn't take that long to nail a 2x up and set a temporary King common and it gives you something to hold that big hip and ridge in place.Yes it can all be figured out mathematically but if and when you do that and you precut your ridge and hips or valleys what's going to hold them up once you get up there.I know time is money but with these sometimes big houses using temporary rafters to set everything in place gives you all your accurate points locations for all your major hips and valleys to be installed first as I do and then I fill in and once everything is held up in place as I get closer to the temporary rafter I just take it out and use it. So as far as the time I think it's a wash because now everything is set comfortably in place and you can all work like gentlemen without struggling 35' feet up in the air. Can you give me the dimensions of the house so I can understand the roof lines?Joe Carola
Edited 11/28/2004 8:29 am ET by Framer
James Hart,
I suspect that the reason you couldn’t find the info on lining up fascias on irregular roofs with your search is because no one bothers to get perfectly precise with this issue. They either use the overhang dimensions to solve the task or they use the soffit material dimension (My preference). In both cases they have cheated the steeper pitch a little to simplify the problem. Also, there are so many different soffit and cornice details to consider that no one formula is going to be perfect for every scenario. (For instance, grooved fascia or sub-fascia w/fascia, sheathing thickness, drip edge, etc.) Too much micro math! I usually make/plane the lesser pitch overhang perfect and this will make the steep side plane in to the fascia a little tighter. Not a big deal as I still pop the sheathing lines the same dim from the fascia’s or drip edge’s edge. This will swoop the steep sides sheathing at the fascia slightly but never enough to notice. It just fits much tighter on that side. See the attached drawings.
This method of fascia placement for irregular hip roofs allows you to use your simple basic calculations for the precut solutions. For equal overhangs, it works for finding the irregular plate rise and run offsets using simple math. The irregular hips can be easily figured and cut based on the length of the offset irregular plate. For the Hard math like finding the length of the Irregular Hip, do as Joe Carola advises and get a CM Pro Calculator. The w/Trig models are even better. They are the best tools for onsite calculations I have found.
You might find more info on the subject over at the JLC’s “Rough Framing” Forum. Search for “Equal overhangs, Irregular pitches”
Happy Holidays All! Richard
Edited 11/29/2004 12:54 am ET by Mr Jalapeno
Nice picture Richard. I'm saving that one. I hope you don't mind. :-) Glad you are posting on this forum.
Thanks for the drawings and the JLC link. I did not know there was a rough framing forum associated with JLC.. Learn something everyday.
I own some old rough framing books but they are obsolete for what we are framing today.
James Hart
joe carola
hi joe this is my first time on this site an in reference to using the Cm for #'s the hip is offset an plate is raised is there a simple method of knowing how much to extend the ridge from the original run# thx
Nextlevel,
You can either use a calculator,layout or a framing square to find the info to cut your irregular hips to get equal overhangs.
The attached graphics will illustrate the process.
I really appreciate the info. I'm feeling a little overwhelmed. It takes me a while to grasp the concepts. But I eventually get there. We have framed for years and even though it turns out right I have known that there are better ways to arrive at the conclusions I need.
I don't know anyone around here who uses a calculator but I suppose it is time I learned.
James Hart
James,Don’t feel overwhelmed, a lot of guys frame for a lifetime and never need to know any of this stuff. The use of a calculator is just the process of using another tool. Some guys like them others don’t.I wrote a pretty decent article in the April 2003 issue of the JLC on laying out irregular hips using just a framing square. You can download the article at their site if you are interested. I think it costs about $3 bucks.
Edited 11/26/2004 10:16 pm ET by Flash
I have been studying your graphics and was wondering if you got those out of a book I could buy.
I have looked at all kinds of framing books and have never seen explanations that clear and concise.
I must admit I'm self taught. I have always loved math and took some drafting classes years ago at the local community college. I read books and ask questions. WE frame lots of houses and I'm constantly learning new techniques but mostly from trial and error.
We are held in high esteem as framers around here and are in much demand. WE get the job done and done right but I always have the nagging feeling that we could have done something better or faster than the way we did it.
Thanks for the help and I'm going to get that article form JLC. I have just recieved my first issue of JLC. I KNOW. I KNOW. WHERE HAVE I BEEN. I used to suscribe to Fine Home Building years ago but it got to where it wasn't doing me any good.
Thanks again for answering my questions.
James Hart
James,I’m sorry, no books they are all original works by me ;-). I have many many more most of them used to be posted here. If you need a graphic to help explain something feel free to ask.
Joe,
Good to see you around :-) I really hope you and the family are doing well. I haven't forgotten to call you, it's just been crazy around here since about last March and it isn't going to stop for awhile (which is good). I hope to get a couple of days of snow and have nothing to do, so I can call you and see how you are doing.
Thanks for the tip. I have looked at that book many times.
How about 7 days of rain nonstop. Too much time off. We workd Friday building the curved roof on the front dormer of that house with the large curved rafters.
STarted raining again Saturday morning so we packed up.
This forum is tremendous when it comes to helpful advice. I amazed at how willing everyone is to share their experience and knowledge.
My two oldest sons work with me(25 and 20 years old) and I'm always telling them to never stop improving your skills and finding smarter and faster ways to do your work. You are never to old to learn and change the way you do things.
James Hart
nextlevel,
Using a CM4 calculator you can use these steps. I first posted them on this forum in 1999. Its been awhile. . .
The example uses a 10/12 12/12 roof combo but you can just replace your roof pitches in the equations.
Using the CM4 for Calculating a Split Pitch Roof.
By Joseph Fusco
Plan Angles:
Press [on/c] [on/c]
Enter [10] [Inch] [Rise] main roof rise
Enter [12] [Inch] [Run]
Press [Pitch] Returns 39.81° or 10"
Enter [90] [-] [Pitch] = 50.19°
This returns the plan angle of 39.81° which is for the 12 pitch rise side of the roof.
Subtracting that angle from 90° returns 50.19° which is the plan angle for the 10 rise side
To get the hip unit run do as follows:
With 39.81° still showing in the calculator.
Press [Diag] gives 15-5/8" if you then Press [Conv] [Inch] it reads 15.6205 the unit run of this hip/valley rafter
Then to get the hip angle
Press [=] [Run]
Press [Pitch] it returns 7-11/16" [Pitch] it returns 32.63° This is the hip pitch angle.
Then to get the hip unit length
Press [Diag] it returns the unit length of 18.55 this hip/valley rafter.
Then with 18.55 still displayed you can get the back bevel
Press [=] [Run]
Enter [12] [Inch] [Rise]
Press [Pitch] this gives 32.90° This is the backing bevel and the plywood bevel cut.
Then to get the hip drop for the 12 rise side
Enter [on/c] [on/c]
Enter [39.81] [Pitch]
Enter [.75] [Inch] [Rise]
Press [Run] Returns .899
Press [=] [Run]
Enter [32.63] [Pitch]
Press [Rise] Returns ... 576
Press [Conv] [Inch] returns 9/16"
The Other Side
Press [on/c] [on/c]
Enter [12] [Inch] [Rise]
Enter [10] [Inch] [Run]
Press [Pitch] This returns the plan angle of 50.19°
To get the hip unit run do as follows:
With 50.19° still showing in the calculator
Press [=] [Pitch]
Enter [12] [Inch] [Run]
Press [Diag] gives 18-3/4" if you then Press [Conv] [Inch] it reads 18.744 the unit run of this hip/valley rafter
Then to get the hip angle
Press [=] [Run]
Enter [12] [Inch] [Rise]
Press [Pitch] it returns 32.63° This is the hip pitch angle.
Then to get the hip unit length
Press [Diag] it returns the unit length of 22.255 this hip/valley rafter.
Then with 22.255 still displayed you can get the back bevel
Press [=] [Run]
Enter [10][Inch] [Rise]
Press [Pitch] this gives 24.19° This is the backing bevel and the plywood bevel cut.
Then to get the hip drop for the 10 pitch side
Enter [on/c] [on/c]
Enter [50.19] [Pitch]
Enter [.75] [Inch] [Rise]
Press [Run] Returns ..625
Press [=] [Run]
Enter [32.63] [Pitch]
Press [Rise] Returns .40
Press [Conv] [Inch] returns 13/32"
Common Rafter lengths:
Enter [14] [Feet] [5] [Inch] [1/4] [Run] Effective run main roof.
Enter [10] [Inch] [Pitch]
Press [Rise] Returns 12' 0-3/8" Effective run 12 side.
Press [Diag] Returns 18' 9-1/2" King Common 10 side.
Press [Rise] [=] [Run]
Enter [12] [Inch] [Pitch]
Press [Diag] Returns 17' 0-3/16" King Common 12 side.
Plywood angles:
To determine the plywood angle on the 12 pitch side.
Press [on/c] [on/c]
Enter [10] [Inch] [Rise]
Enter [12] [Inch] [Run]
Press [Diag] Returns 15-5/8" Unit Hip Run
Press [Pitch] Returns the angle 39.81° Press [Pitch] again to Return the measurement of 10"
Enter [=] [Run]
Enter [12] [Inch] [Pitch]
Press [Diag] Returns 14-5/32"
Enter [=] [Pitch]
Press [Pitch] Returns 49.68° To get the jack side cut angle just subtract 49.68 from 90° which is 40.°
Enter [15] [Inch] [5/8] [Rise] Unit hip run
Press [Pitch] Returns 57.37° To get the jack side cut angle just subtract 57.37° from 90̊ which is 32.62°
Jack Rafter Common Difference:
To determine the common difference on the 10 pitch side.
Press [on/c] [on/c]
Enter [57.37][Pitch]
Enter [24] [Inch] [Run] On Center measurement.
Press [Rise] Returns 37-1/2"
To determine the common difference on the 12 pitch side.
Press [on/c] [on/c]
Enter [49.68][Pitch]
Enter [24] [Inch] [Run] On Center measurement.
Press [Rise] Returns 28-9/32"
Jack Rafter Offsets:
To determine the jack rafter offset on the 10 pitch side.
Press [on/c] [on/c]
Enter [32.63] [Pitch] This is the jack side cut angle for the 10 side.
Enter [3.5] [Inch] [Run] This is the Total Thickness of the hip.
Press [Diag] Returns 4.156
Enter [=] [Run]
Enter [57.37] [Pitch] This is the plywood angle for the 10 side.
Press [Rise] Returns 6.49
Enter [÷] [2] [=] 3.245 This is the length of a line measured from the center of the ridge to the long point of the jack rafter.
Press [on/c] [on/c]
Enter [.75] [Run] This is half the thickness of the King Common.
Enter [57.37] [Pitch]
Press [Rise] Returns 1.171
Press [Conv] [Inch] Returns 1-3/16"
Enter [3.245] [-] [1.171] [-] [.75] [=] 1.325
Press [Conv] [Inch] Returns 1-5/16"
Enter [+] [37] [Inch] ½ [=] Returns 38-13/16". 37-1/2 is the common difference for the 10 side.
Enter [18] [Feet] [9] [Inch] [½] [-] [38] [Inch] [13/16] [=] 15' 6-11/16.
To determine the jack rafter offset on the 12 pitch side.
Press [on/c] [on/c]
Enter [40.32] [Pitch] This is the jack side cut angle for the 12 side.
Enter [3.5] [Inch] [Run] This is the Total Thickness of the hip.
Press [Diag] Returns 4.59
Enter [=] [Run]
Enter [49.68] [Pitch] This is the plywood angle for the 10 side.
Press [Rise] Returns 5.41
Enter [÷] [2] [=] 2.704 This is the length of a line measured from the center of the ridge to the long point of the jack rafter.
Press [on/c] [on/c]
Enter [.75] [Run] This is half the thickness of the King Common.
Enter [49.68] [Pitch]
Press [Rise] Returns .883
Press [Conv] [Inch] Returns 7/8"
Enter [2.704] [-] [.883] [-] [.75] [=] 1.071
Press [Conv] [Inch] Returns 1-1/16"
Enter [+] [28] [Inch] [9/32] [=] Returns 29-11/32". 28-9/32" is the common difference for the 12 side.
Enter [17] [Feet] [0] [Inch] [3/16] [-] [29] [Inch] [11/32] [=] 14' 6-13/16".
Using the Conv Hip/V Function.
Plan Angles:
Press [on/c] [on/c]
Enter [10] [Inch] [Rise] main roof rise
Enter [12] [Inch] [Run]
Press [Pitch] Returns 39.81° or 10"
Enter [90] [-] [Pitch] = 50.19°
Effective runs:
14' 5-1/4" 10 pitch side.
Enter [10] [÷] [12] [x] [14][Feet] [5] [Inch] [1/4] [=] 12' 0-3/8"
Enter [on/c] [on/c]
Enter [1.5] [Inch] [Run] Thickness of common rafter
Enter [50.19] [Pitch] Plan angle 10 pitch side.
Press [Rise] Returns 1.80 or 1-13/16
Enter [on/c] [on/c]
Enter [1.5] [Inch] [Run] Thickness of common rafter
Enter [39.81] [Pitch] Plan angle 12 pitch side.
Press [Rise] Returns 1.25 or 1-1/4"
Enter [on/c] [on/c]
Enter [1.75] [Inch] [Run] ½ Thickness of hip rafter
Enter [50.19] [Pitch] Plan angle 10 pitch side.
Press [Diag] Returns 2.73 or 2-23/32"
Enter [on/c] [on/c]
Enter [1.75] [Inch] [Run] ½ Thickness of hip rafter
Enter [39.81] [Pitch] Plan angle 12 pitch side.
Press [Diag] Returns 2.28 or 2-9/32"
Enter (2-3/4 - 1-13/16) - (14' 5-1/4) = 14' 4-5/16" 10 side.
Enter (2-9/32 - 1-1/4) - (12' 0-3/8) = 11' 11-11/32" 12 side.
Enter [on/c] [on/c]
Enter [10] [Inch] [Pitch] Main Pitch
Enter [14] [Feet] [4] [Inch] [5/16] [Run]
Enter [12] [Inch] [Conv] [Hip/V] Other Pitch
Enter [24] [Inch] [Jack] On Center spacing.
Press [Jack] Returns 15' 6-13/16" Press until zero.
Enter [on/c] [on/c]
Enter [12] [Inch] [Pitch] Main Pitch
Enter [11] [Feet] [11] [Inch] [11/32] [Run]
Enter [10] [Inch] [Conv] [Hip/V] Other Pitch
Enter [24] [Inch] [Jack] On Center spacing.
Press [Jack] Returns 14' 6-7/16" Press until zero.
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