Replies

1. 
   Soultrain | Aug 15, 2005 04:46am | #1

   Once you have one stud in place, measure it & then use the roof pitch to calculate how much to take off each adjacent stud.

   I'll use my roof for example:  Roof pitch = 7/12 & stud spacing is 24"OC (which makes it pretty easy since 24 = 2*12), so as I move out, I take 14" off of each preceding stud.

   If stud spacing was 16" OC, (which = 4/3 * 12), I'd do 4/3*7 which is just a hair over 9 5/16"

   Note: the middle stud (the one directly under the ridge) doesn't count since it doesn't meet the rafter.

2. 
   Hooker | Aug 15, 2005 05:02am | #2

   It works for me to snap the actual wall out on the floor before I build it.  I haven't the calculative ability to figure these things, so this may not answer your Q. 

   I clear a big enough space to accomodate the wall on the floor and mark and snap every stud, plate, window, etc.  The results have been very accurate, although only as accurate as my cutting ability!

   I get paid to do carpentry.  That makes me a professional.

   If I work on my own house does that make me a DIY?

3. 
   Ronbaby | Aug 15, 2005 05:22am | #3

   posts #2 and #3 work well in theory, but with any crown in the lumber, the lengths are bound to change somewhat. Measure and cut.

1. 
   Hooker | Aug 16, 2005 09:46am | #11

    

   posts #2 and #3 work well in theory, but with any crown in the lumber, the lengths are bound to change somewhat. Measure and cut.

    

   Measure and cut each piece, put it into the rake wall diagram, use that one to figure the next one.  IE: Cut all the plates and tack them together.  Figure and cut the studs.  nail them in place.  Continue through the entire wall.  Yes, it takes more time and steps, but the accuracy is dependable.

   Use good lumber, get little or no crown.  Some walls deserve to be culled out for a better finished product.I get paid to do carpentry.  That makes me a professional.

   If I work on my own house does that make me a DIY?

4. 
   robert | Aug 15, 2005 07:13am | #4

    Once the gable rafters are up, find two nice straight studs, place them on the layout in the middle of each rafter, plumb up and mark. Cut, nail in at the plate and use to lift and sag in the rafter if the need is there.

   rack some 2X's up on a bench and cut the appropriate bevel on both ends. FInd a nice straight 2X and grab your level. PLace the 2X on the plate, plumb and mark for each stud on the 2x. Now you can use that 2x as a story pole of sorts. By lining the long or high side of each mark up with a bevel cut and then marking the bottom of your story ploe 2X, you've just transferred the length.

    Cut and nail in being careful not to jack the gable rafter up.

    It's 100 times easier and faster than it sounds.

1. 
   midway | Aug 15, 2005 08:57am | #5

   Thanks guys I appreciate the input....I've been cutting them in place, measuring and cutting each as I go along the bottom plate layout...the storypole sounds good....would it be too long to measure the smaller rake studs as you went along?

5. 
   BossHog | Aug 15, 2005 02:34pm | #6

   I've tried using spreadsheets for feet-inches-sixteenths stuff, and it's a pain in the neck.

   I think you'd be a lot better off with a construction master calculator. In the instruction manual they have a lot of info about how to calc stuff.

   Okay, who stopped the payment on my reality check?
1. 
   midway | Aug 15, 2005 11:45pm | #7

   Thanks BossHog,  have a CM and use it for all rafter lengths and hips.  I believe that for a 2X for every 1" of pitch your rake wall grows or shrinks an 1/8".  Much like the Valley Framing article in FH awhile back - the theoretical and the true lengths was what I was trying to get a grip on for some reason I have a brain freeze when it comes to Rake Wall Math..Oh well will just follow your suggestions and see if I can find something that is efficient and easy for me...

1. 
   ~~framer | Aug 16, 2005 02:34am | #8

   A rake stud is just another Triangle to figure out. Let's asy you cut your seatcut at 3-1/2" for a 2x4 wall. That means the bottom of the rafter is flush with the inside of the top plate. That plus the measurement to the layout mark to the lomg point of the rake stud is all you need.So if you have a 7/12 pitch roof and your measurement from the inside of the top plate which is also the bottom of your rafter and the beginning of your Triangle is 98" to the long point of your longest rake stud to the layout mark. That is your RUN. 7/12 PITCH.Using CM Calculator.98[Inch] [Run]7 [Inch] [Pitch][Rise] Returns - 57-3/16" (Rake Stud #1)[Conv] [Rise] Returns - 47-13/16" (Rake Stud #2)[Rise] Returns - 38-1/2" (Rake Stud #3)[Rise] Returns - 29-3/16" (Rake Stud #4)[Rise] Returns - 19-13/16" (Rake Stud #5)[Rise] Returns - 10-1/2" (Rake Stud #6)Any Calculator or CM Calculator.98/12 = 8.166667 x 7 = 57.16667" or 57-3/16" (Rake Stud #1)16/12 = 1.333333 x 7 = 9.333333" (16" Center Jack Difference)57.16667 - 9.333333 = 47.83334" or 47-13/16" (Rake Stud #2)[=] - 38.5" or 38-1/2" (Rake Stud #3)[=] - 29.16667" or 29-3/16" (Rake Stud #4)[=] - 19.83334" or 19-13/16" (Rake Stud #5)[=] - 10-5" or 1-1/2" (Rake Stud #6)Your first Triangle as you will see has a Run of 98" and a Rise of 57-3/16".Your second Triangle as you will see has a run odf 82" and a Rise of 47-13/16".Joe Carola

   Edited 8/15/2005 7:49 pm ET by Framer

1. 
   RayJay | Aug 16, 2005 06:39am | #9

   Im suprised knobody mentioned a framing square. It has all the information you need to frame just about anything on a house.

2. 
   menken | Aug 16, 2005 07:51am | #10

   Wow, Joe. You do all that on your calculator? Try this: L=(cosA)x16Solving for L, where L is the additional length of the next stud and A is the angle of the slope (e.g., 30.25 deg. for a 7/12 slope)... And 16" is your stud spacing in this case. For 24" studs, just substitute 24 for the 16 in the equation. For 16" stud spacing, I get 13.8" for the additional stud length. What did you get?If one didn't know the angle of the slope off hand, it's simply the arctan of the slope fraction (e.g., arctangent of 7 divided by 12, for a 7/12 pitch, = 30.25 degrees). But it's already on your speed square/framing square as someone mentioned.BTW, I always used the chalk-line-snapped-on-floor method for framing rake walls.. Always turned out much more accurate than applying the math--was quicker--AND as a bonus, I always knew my rakes were right BEFORE I stood them up.

1. 
   ~~framer | Aug 16, 2005 12:15pm | #12

   "the theoretical and the true lengths was what I was trying to get a grip on for some reason I have a brain freeze when it comes to Rake Wall Math.."That is what Midway said in his last post.He was just concerned about the math behind it. He wasn't asking about the framing square which can easily be used. My post to him was just to give him a couple ways to do it using math. I use a Construction Master Pro Trig Plus 3 and there's many ways to figure out rake studs the angles and any roof using it.It sounds like to me that he has his gable end up already and then puts the rake studs in afterwards. Precutting them using math works after the gable is up first but is not as accurate as scribing the studs in because of any variation in the plate or the rafter but works.If I frame a rake wall with the rafters on the deck first like you said I do the same as you with the chalklines.Menken, You said this, "Try this: L=(cosA)x16""Solving for L, where L is the additional length of the next stud and A is the angle of the slope (e.g., 30.25 deg. for a 7/12 slope)... And 16" is your stud spacing in this case. For 24" studs, just substitute 24 for the 16 in the equation. For 16" stud spacing, I get 13.8" for the additional stud length. What did you get?"Using my Calc, cos(30.25) x 16 = 13.82137" is what I get. But what does that mean? Are you saying that 13.82137" is the differnce between the rake stud? If so that's not correct.It's: L=(tanA)x 16"My Calculator.7/12 = .583333[Conv] [Tan] Returns = 30.25644°[Tan] Returns - .583333 x 16" = 9.333333" (Additional Stud Length)All you have to do which is another way to get the stud difference is this.7/12 = .583333 x 16 = 9.333333".583333 is the Tangent of the angle.Or this.7 [Inch] [Pitch]16 [Inch] [Run][Rise] Returns - 9.33333"Joe Carola

2. 
   MrJalapeno | Aug 16, 2005 03:11pm | #13

   This is another way to do it.

    <!----><!---->

   Using a pencil and paper, long hand calculations:

    <!---->

   7 in 12 pitch, 16” o.c. as an example:

    <!---->

   7/12 x 16/1 = 112/12

    <!---->

   112 divided by 12 equals 9-4/12”, or 9-1/3”, or 9.333”

    <!---->

   I lay out Gable walls just like Hips, from center, giving me two studs of equal length from center and one bracing stud under the ridge.  I pre cut the fingers with the 1-1/2” by rafter height removed to nail to the gable rafter.  Lay all the studs on the horses, on edge, staggered on rise (9-1/3"), and measure the longest from the finger, square across, gang-cut.

3. 
   guyatwork | Aug 16, 2005 03:11pm | #14

   I think Joe C. is probably as good a framer as you will find and definitely the smartest.

   That said, I've never worked on a framing crew (I've only been on a few), nor hired one (I've hired many more than I've worked) that did all that math to figure out something as simple as a rake wall.  A method similar to what Robert described above is the norm.  I have had framers use the Construction Master for doing bastard hips, etc, but more often than not they just do some measuring, use their levels and framing squares. 

   I think there is a tendency for novices to over analyze and there fore over complicate a simple task such as the the rake wall example.  The reality of it is that lumber is not straight, nor is it exactly uniform in dimension, the house may not be exactly plumb/level so in the end crews end up doing what works (cut to fit) and leave the theory to the people on the drawing board.

   I do think that someone like Joe is gonna save time by using his calculator, but that is because he does it every day. 

   OK - now flame me... :-)

4. 
   ~~framer | Aug 16, 2005 05:47pm | #16

   Thanks for the compliment Matt.There's a lot of good framers out there. I just like to experiment different ways and finding the fastest way with accuracy to do things. I didn't start using the CM until 3 years ago. Everything I did was from my framing square and learning on the field and that's what helps me put into the Calculator what needs to go there.Everyone does what is comfortable for them. I was taught to frame the walls first and stand them up with no sheathing and go back with precut gable studs and nail them in later which worked but not that good because back then guys were using crowned gable rafters and a little variation with the plates most of the gable studs weren't plumb but were good enough to nail the sheathing on.Second framing crew I worked on used a straight 2x4 and a level and scribed every gable stud and then cut them on a bench. That to me is the fastest way and you can't go wrong. It only takes a few minutes to scribe.Some people ask questions on how to figure things with a calculator like Midway did and doesn't mind the math behind it. Some people aren't comfortable with the math which is great also so we can help and give different ways of doing things like everyone here is doing.Here's a couple ways I used to get the Gable Stud difference using the framing square on a sheet of plywood which takes about 15 seconds to do each way.Joe Carola

   
5. 
   midway | Aug 20, 2005 09:08pm | #17

   Thanks for all the input guys...Joe C was right usually frame the rafters in first, put lookouts in and frame up to either a top plate attached to the bottom of the lookouts or frame up to the lookouts nailing into the sides measuring each rake wall stud.  Was wondering what is the best method as this method always works fine but it seems to be inefficient to me for some reason.  Maybe an article in FHB about this topic - similiar to the article on jack differences in hip roofs as featured in the FHB picutre on the Taunton Press Home Page would be very cool.  Math and actual measuring methods would probably work well.

6. 
   Framer | Aug 23, 2005 02:17am | #18

   How do you normally figure your hip jacks, do you use the measurement on the framing square?Joe Carola

7. 
   midway | Aug 30, 2005 05:10pm | #19

   Hi Joe...usually place the framing square on the last common....where the tongue of the square hits - mark the hip and then pull out the old tape measure...have used the cm calculator when by myself pre cut and then install...

8. 
   menken | Aug 16, 2005 03:35pm | #15

   Absolutely right, Joe. My brainfart. It is 16(tanA)--not Cosine! Since slope is the tangent of A, the slope angle (on the speedsquare) times the stud spacing equals the length difference.Three operations on the calculator--no trig even necessary..Case in point: the chalk method is faster..and less prone to math errors like mine(!).