Replies

1. 
   Guest_ | Oct 30, 1999 05:04pm | #1

   *
   Mark,

   Question 1: Do you plan to put the hip rafters directly over the corners ( which will result in more overhang on the 10/12 sides than the 14/12 sides), or are you attempting to keep the overhangs equal around the perimiter of the building? ( which would require that you offset the hip rafters from the corners and move them completely onto the 14/12 plates. You would also have to raise the plate heights from hip to hip on the 14/12 plates to accomplish this). I would recommend option 1.

   Question 2: What is the measurement from the last 14/12 common rafter to the corner of the building, in other words, what is the RUN for the 10/12 common rafters?

   Question 3: Do you normally use a framing square with stair gauges to cut rafters, or do you use an "angle square" ( speed square )?

2. 
   Mark_S._Lovelace | Oct 30, 1999 07:12pm | #2

   *
   The plans do not specify a length for the common rafters of the 10/12 gable. They scale (which I do not normally do) aprox. 4' which of course requires building a 14/12 pitched gable wall up to these rafters. The wall then levels out to effectively create a higher end wall that the 10/12 hip is built upon. Figuring the hight of this wall based on the run of 4ft. (or whatever) is straight forward enough, but figuring out how long the top plate should be relative to where the hip locates is a problem. The hip rafters do not frame in at 45deg. from the commons since the other requirement of this style roof is for them to plane in with the 14/12 commons. At this point we used trial and error with straight-edges to swing the hips in an arc to find where they planed in with the 14/12 commons. What you eventually wind up with is a part hip/part gable roof, the topmost 1/4 or so of the roof is hip the other 3/4 is gable.

   I always use a framing square and stair guages to cut rafters.

3. 
   Guest_ | Oct 30, 1999 08:47pm | #3

   *
   Mark,

   If I am reading your last post correctly, it sounds to me that the roof style that you describe is not a dutch hip, but rather, a "tudor hip". True?

   If so, you can determine the length of the the plate in the following way

   4' x 10/14 = 2' 10 5/16"

   Then double it

   2 x 2' 10 5/16" = 5' 8 5/8"

   Put the hips out on the corners.

   The bevel for cutting the 10/12 jacks is 54 1/2 degrees, and 35 1/2 degrees for the 14/12 jacks. The hips will cross the plate at these same angles ( not 45 degrees )

   Since the hips are so small, I'd consider cutting backing bevels on them to get them to truly plane in properly. Otherwise you'll have to fake it a little, as you would with any double pitch roof hip.

   On the 14/12 side of the hip, measure down 9/16 square to the hip and scribe a line the entire length on this side. Set the saw bevel at 38 degrees and cut. On the 10/12 side, measure down 5/16 and cut at 22 degrees.

   The plumb cut for the hip using a framing square is 10 3/16" on the tongue, and 15" on the body or blade. This is the same as 34 degrees using an angle square.

1. 
   Guest_ | Oct 30, 1999 09:17pm | #4

   *Mark,

   For openers, why are there two different "slopes" to each of the roof sections? In a standard "Dutch" roof they would be the same. The "height" of the Gable end or the "length" of the hipped section is "controlled" by the location of the "last common rafter" on the Gable end wall. The closer you move it to the "front" edge of the building, the more of a Gable end you'd get. The further back from the edge of the building the more "hip" you'd get. Did you "scale" these slopes or were they called off on the plan?

   Joseph FuscoView Image"The price of apathy towards public affairs is to be ruled by evil men." -- Plato

4. 
   Mark_S._Lovelace | Oct 31, 1999 03:42pm | #5

   *
   Dear Joe,
   The architect specified the different slopes. We have three different slopes on the roof 8/12,10/12, and 14/12. And yes you are right about the size of the hip being determined by the location of the last common rafter. That location was not spelled out specifically. As for the name of the hip type, not having encountered it here in the San Francisco area before, someone told me that it was called that. I really don't know what it is. Sorry.
   Sincerely, Mark

1. 
   Mark_S._Lovelace | Oct 31, 1999 03:52pm | #6

   *Dear Ken,Thanks so much. The numbers look right compared to what we came up with in our "trial and error" method. We just didn't have the math. Would you care to comment further on how you arrived at your calculations? Dutch hip, tudor hip, honestly I haven't a clue. Someone said it was a dutch hip and I took their word for it. I've seen it on houses in books and magazines etc. but never heard a name for it, nor have I ever built one before.

5. 
   Guest_ | Oct 31, 1999 04:43pm | #7

   *
   Mark,

   I'd like to provide you with a little more information about how to frame the "tudor hip".

   After all of the 14/12 common rafters are in place, you'll have the last one at the end of the ridgeboard. There also will be a 10/12 common rafter that butts to the end of the ridge board and is then nailed to the center of the "tudor plate". ( this rafter is sometimes referred to as the "king" rafter ) Based on a run of 48" we've already seen that the length of the tudor plate is 5' 8 5/8". The center of the tudor plate will be at 2' 10 5/16", which becomes the layout for the center of the 10/12 king rafter.

   Now, how about the layout for the very last 14/12 rafter at the end of the ridge board?

   Normally, if both roof pitches were the same, you would put the CENTER of this last 14/12 rafter at 48" from the corner of the building. But, because you are working with a 14/12 in combination with a 10/12, this "framing point" is no longer on the center line of the last 14/12 rafter.

   Make a square line on the plate at 48". Measure 1 1/16" towards the corner and make a second square line. This is the layout for the last 14/12 common rafter at the end of the ridge board. In other words, the measurement from the corner to this rafter is 46 15/16". It also is the RUN of the 10/12 king rafter, since the ridge board will end 46 15/16" from the tudor plate.

   So, to find the length of the 10/12 king rafter, use 46 15/16 as the run. By my calculations, the length of the rafter would be 61 1/8".

   I'll finish by making a few comments about the correct height of the tudor plate.

   First, when you cut the birdsmouth for 10/12 king rafter and the 10/12 jacks, make sure that the plumb measurement above the "heel" cut of the birdsmouth ( the HAP ) is the same as it is on the 14/12 rafters. ( I'll assume that you are using 2x6 rafters and that this measurement is 4 1/4" in the discussion below)

   Now let's calculate how far below the top of the main ridgeboard that the tudor plate would be.

   46 15/16" run at 10/12 pitch = 39 1/8" RISE

   ADD the HAP, which we are assuming to be 4 1/4" to it.

   39 1/8" + 4 1/4" = 43 3/8". So the tudor plate is 43 3/8" below the top of the ridge board.

   Good luck Mark. Hope some of this is helful to you, and others.

1. 
   Guest_ | Oct 31, 1999 07:17pm | #8

   *Mark,

   For the sake of correctness, I just would like to know what your roof looks like, A or B?

   A) B) Joseph FuscoView Image"The price of apathy towards public affairs is to be ruled by evil men." -- Plato

6. 
   Mark_S._Lovelace | Nov 01, 1999 04:04am | #9

   *
   Joe,

   The roof looks like B.

   Mark

1. 
   Mark_S._Lovelace | Nov 01, 1999 04:15am | #10

   *Ken,Thank you again for your very precise instructions. They will be invaluable to me.I would like to know how the calculation for the lenth of the plate was made. Specifically where did the formula "4'x 10/14=2'10 5/16" come from? I see both of the pitches involved here, but how do they relate in the formula. Maybe I'm getting in over my head, but it intrigues me. Is there a text you could recommend that explains this type of framing calculations? Thanks again,Mark

7. 
   Guest_ | Nov 01, 1999 06:07am | #11

   *
   Mark,

   I'm glad that you found my comments helpful.

   I really can't recommend a text book to you to study the fine points of this type of framing. I became frustrated reading material about this type of construction a long time ago, so I set out to understand it on my own. With a lot of hard work and determination, I learned that I could find all of the answers to my questions, regardless of the complexity of the situation. I have a strong background in mathematics, which made it easier to find my way. I hope to publish something on the subject in the near future. Positive feedback from people like yourself, encourage me to do so. Thanks for the boost.

   In the meantime, I enjoy helping out folks like yourself that run into these type of problems. I watch for posts that deal with roof framing problems and other mathematically challenging problems, and make an effort to respond. There are others here at Breaktime that also make such an effort and contribute very good information.

   So when you ask me, " specifically, where did the formula,
   4' x 10/14 = 2' 10 5/16" come from" I can only say that it came from my head. It's just the way things work out in these situations. If you run into this problem again Mark, just remember to multuply the run ( to the framing point ) of the end rafter by the ratio of the roof pitches, whatever they are, to find 1/2 the length of the "tudor plate". Then just double the result to find the length of the plate.

   Look forward to more conversation with you in the future.

1. 
   Guest_ | Nov 01, 1999 08:05am | #12

   * Mark,

   Your reply was to the "point" to say the least. Now that I'm sure of the roof your building/built, I can feel more confident about my reply.

   To answer your last questions in reverse order. Marshall Gross's book from the Craftsman Press will help you out, also The Roof Framers Bible (Ken recommends it) is said to be a good book even though I've never read it.Upon rereading your post (2) it appears to me that the location of the end of your ridge might be incorrectly placed. The working angle of the hips should be 54.462. Working from pure numbers and not taking in to account any thickness's or HAP measurements, if your Hip end is a 10/12 slope the ridge should be set back 36" from the outside edge of Gable end wall. If you follow this, this will produce three units of run. Since the unit length of a 10/12 slope is 15-5/8" this will give the length of a common rafter at 3' 10-7/8". This is almost exactly what you called for. Knowing this you can now figure the length of the hip rafters to 4'-5 7/16", how to figure the hip is self explanatory. With all this information I come up with a length of 4'-3 7/16" to the framing points for the Tudor Plate?How you figure the length of the Tudor Plate is as follows, using the common rafter length 3' 10-7/8" as the rise and the hip rafter length 4'-5 7/16" as the hypothenuse of the right triangle they form, the "run" is equal to 2' 2-23/32". Since this triangle is half of the larger Isosceles triangle that is formed by this hip roof, adding them together gives you the length of the Tudor Plate.

   P.S. it's been along day. . .

   Joseph Fusco <img

1. 
   Guest_ | Nov 01, 1999 02:33pm | #13

   *Joe,The reason that I used 4' as the run of the common rafter to the framing point instead of 3', as you suggest, is that Mark said that's what the run of the common rafter scaled out to be, not the length of the tudor plate. ( See his second post in this thread )

1. 
   Guest_ | Nov 01, 1999 02:59pm | #14

   *Ken,

   He states in his second post(2) the LENGTH (not the run) of the COMMON rafter is Approx. 4' for the 10/12 hip roof.

   Joseph FuscoView Image"The price of apathy towards public affairs is to be ruled by evil men." -- Plato

1. 
   Guest_ | Nov 01, 1999 05:23pm | #15

   *Joe,I was referring to sentence 4 of his post "figuring the height of this wall based on the run of 4 ft"I realize that in sentence 2 he says that the common rafters scale at 4 feet, but I just assumed that since he was scaling, that measurement would represent the run. Apparently he did also, and he clarifies that in sentence 4 (above)

2. 
   Guest_ | Nov 02, 1999 01:08am | #16

   * Ken,

   All I can say in your defense is you should have picked up the contradiction. You could only have a common rafter length of 4' with a run of 4' if the roof were flat (level) but, in this case it's a 10/12, very far form flat.

   Joseph Fusco View Image

8. 
   Mark_S._Lovelace | Nov 02, 1999 05:31am | #17

   *
   Dear Ken,
   I could only assume that the run to ratio of the roof pitches formula would work in any similar situation, glad you clarified that for me.

   Write your book. I know I'd buy it.

   My appologies to Joe for the confusion in my messages.

   Glad I ran into you. I'll let you know how they come out. We just finished spreading the trusses on the rest of the house. They had to be shipped in two sections because of the hight. The top trianguler sections, yet to be installed, are a little over 8' high. We have a small crane coming to set those one by one.

   Sincerely, Mark

9. 
   Guest_ | Nov 02, 1999 05:43am | #18

   *

   Mark,

   Theres no need for apologies to me. I found nothing confusing in your threads. I just like to wait to all the facts are in before making any remarks. If you are interested you might read this.

   Joseph Fusco

   View Image

1. 
   Guest_ | Nov 02, 1999 03:45pm | #19

   *Joe,In one of your posts in this thread, you demonstrated how to find the length of the tudor plate using right triangles, based on a situation where the ridge board stopped exactly 3' from the outside of the tudor plate.You concluded that the length of the tudor plate is 4' 3 7/16". This measurement is 1 1/2" short. Let me explain why.The triangle that you used to calculate 1/2 the length of the tudor plate lies completely on one side of the 10/12 "king" rafter that runs to the tudor plate. When you double your result, you must then add to it the thickness of the common rafter, or 1 1/2". So the correct length of the tudor plate using your method would be4' 3 7/16" + 1 1/2" = 4' 4 15/16"Notice that if you find the length of the tudor plate using the method that I described to Mark earlier in this thread, that you arrive at the same result. The run of the 10/12 common rafter to the framing point is 3' 1 1/16". If you multiply this by the ratio of the roof pitches and then double it, you'll get the length of the tudor plate3' 1 1/16" x 10/14 x 2 = 4' 4 15/16"To find the measurement that the framing point lies beyond the end of the common rafter plumb cut, 3/4" x 14/10 = 1 1/16"

1. 
   Guest_ | Nov 03, 1999 12:51am | #20

   *Ken,

   Let me explain why I don't give a shit what you say. You can't read, its that simple. I stated the length was in terms of "pure" numbers. In the future save your words and hieroglyphics for others, I'm unimpressed.

   Joseph FuscoView Image"Whenever, therefore, people are deceived and form opinions wide of the truth, it is clear that the error has slid into their minds through the medium of certain resemblances to that truth." Socrates

1. 
   Guest_ | Nov 03, 1999 01:45am | #21

   *Ken,

   I just can't help myself. . . You know what they say, once you get them drunk, mug em!

   Let's see now about this "wrong" business. . .You stated in post (3.). . . "If so, you can determine the length of the the plate in the following way 4' x 10/14 = 2' 10 5/16" Then double it 2 x 2' 10 5/16" = 5' 8 5/8" " You make "no" adjustments or modifications to this number in your post.Now, lets see . . .using your equation. . .3' x 10/14 = 2' 1 23/32"Then double it2 x 2' 1 23/32" = 4' 3 7/16" Holy shit, look at that, I guess your number is really wrong.I think you better "QUIT" while your "BEHIND" or this could get ugly.

   Joseph FuscoView Image"Whenever, therefore, people are deceived and form opinions wide of the truth, it is clear that the error has slid into their minds through the medium of certain resemblance's to that truth." Socrates

1. 
   Guest_ | Nov 03, 1999 04:17am | #22

   *Hi Joe,Just got home from a hard day at work. I'm right in the middle of cutting a split pitch 7/12-9/12 hip/valley roof.When I walked into my home, my dog jumped up and gave me a big lick on my face, and my girfriend gave me a big kiss. Felt good. Then I read your 2 posts.I'm not going to take time out from my life this evening to respond to your nasty comments, but I will when I have some free time, perhaps later in the week, or on the weekend. By the way, I'm not going to take your advice when I do, which was, "QUIT while your BEHIND, or this could get ugly.", as you stated in your last post.If it does get ugly, it's only going to be from your side, not mine.In the meantime, I know you own a copy of "ROOF FRAMING" by Marshall Gross. Would you please reread his discussion on "framing points", and notice, when you do, that you allowed the run of your 3' common 10/12 rafter to be a full 3', where I allowed the run of my 4' common rafter to be only 3' 10 15/16", because I was taking the framing point into account?

2. 
   Guest_ | Nov 03, 1999 04:23am | #23

   *Ken,

   Book sales will suffer. Your dead now, roll over.

   Joseph FuscoView Image"Whenever, therefore, people are deceived and form opinions wide of the truth, it is clear that the error has slid into their minds through the medium of certain resemblance's to that truth." Socrates

3. 
   Guest_ | Nov 03, 1999 07:43am | #24

   *Joe, The problem that you are having with this is in your calculations based upon what you refer to as "pure numbers", in one of your previous posts."pure numbers", as you call them, are not 1 1/2" wide.If you want to use one of the "legs" of a right triangle to determine 1/2 the length of the tudor plate, then you must have this line SPLIT THE CENTERLINE of the 10/12 common rafter to the the tudor plate. In other words, you must find its length to the "framing point", the point where the center lines of the hip rafters intersect.If the ridge board stops exactly 3' from the outside of the tudor plate, as in the example that you gave, then the run to this framing point is 3' 1 1/16". ( 3' + 14/10 x 3/4" ) If you now proceed with your method, finding the length of the common rafter and a hip rafter to this point, you would find that the "line length" of the common rafter would be 4' 0 1/4" (rounded) and that the "line length" of the hip would be 4'7" (rounded) If you now use the pathagorean theorem to find 1/2 the length of the tudor plate using 4' 0 1/4" as one of the legs, and 4' 7" as the hypotenuse, you would find that 1/2 the length of the third side when doubled would be 4'4 13/16", the slight difference in the length as I described in an earlier post ( 4' 4 15/16" ) due to rounding.But once again, why go through all of these uneccessary calculations and solving right triangles, when all you need to know is the RUN of the common rafter to the framing point, 3" + 14/10 x 3/4" = 3' 1 1/16".Multiply by 10/14 and doubled it = 4' 4 15/16"Why go into 3-D, to solve a problem that can be solved in 2-D ?

4. 
   Guest_ | Nov 03, 1999 03:01pm | #25

   * Ken,

   The problem your having is your failing to cloud the issue with the VOLUME of words and hieroglyphs that you set forth. Now your becoming a bad politician. My suggestion is that you email your remarks to yourself, it appears that your the one in need of them. I will also suggests that you reread the thread to save yourself any further embarrassment.

   Joseph Fusco View Image

5. 
   Guest_ | Nov 04, 1999 06:08am | #26

   *Joe,Embarrassment? For passing on ACCURATE information in an effort to help others? I don't think so.I demonstrated 3 different ways to find the length of the tudor plate, (two of them based upon your method), and showed that the end result was the same using any of the three methods. How about doing all of us ( and especially yourself ) a big favor, Joe? Make one of your CAD drawings, showing the 10/12 common ( king ) rafter, the ridge board, the 14/12 common rafters at the end of the ridge board, the tudor plate, and the hip rafters, of the situation that you describe, the ridge board ending exactly 3' before the outside of the tudor plate, and demonstrate that the correct length of the tudor plate in this situation is, as you say, 4' 3 7/16", instead of the correct measurement of 4' 4 15/16".

6. 
   Guest_ | Nov 04, 1999 07:16am | #28

   * Ken,

   No, for being a person who has made an error and not being able to admit it.

   As far as anything else. . . Refer to post (15.1).

   Joseph Fusco View Image

10. 
    Mark_S._Lovelace | Nov 04, 1999 07:16am | #27

    *
    We are building a home with a 14 in 12 pitch roof that is designed to have a dutch gable at each end with a 10 in 12 pitch. How do I lay out the 10 in 12 hip so that it planes with the 14 in 12 pitch of the commons (and the hip jacks that intersect with the hip rafter of the Dutch gable). We built one using the trial and error method, but there must be a better way.