Bare with me – I’m an apprentice.
Ok so I’m going to frame a new gable roof over an entrance.
The main roof is 3/12, I want to build a 114″ total width/72″ deep gable roof over top. 2′ OH.
If I build it at 3/12 the peak will only be about 17″ from the top of the outside wall. Not what I’m looking for.
If I build at 3/12 my rafters are 64.125″ which doesn’t make great use of the rule of 4s.
I don’t want to fake it till I make it – I want to cut the ridge beam, rafters and roof cleats on the ground and build it all at once.
Any advice on what pitch I should make the entrance gable? This is my house so I can do as I please (as long as I ask the wife first). Should I knock it up to 5/12?
Also anyone know where I can find a coles notes online for multi pitch roofs?
Replies
Not sure what the rule of 4's is, or what exactly your question is. Can you post a photo or drawing?
Sounds like you're framing a California valley over an existing roof. Piece of cake, not really a multipitch roof ques., if that's the case. Cut your rafters with a level cut at the bottom, and then set your sawblade to the angle of the existing roof when you cut.
Sorry, I'm probably missing something.
CaliforniaRemodelingContractor.com
Any advice on what pitch I should make the entrance gable? This is my house so I can do as I please (as long as I ask the wife first). Should I knock it up to 5/12?
That's a tuff question without seeing the house.Post a picture of the front of your house. It's a question that really can't be answered unless we see the house. Usually those roofs never have a low pitch of 3/12. At least everyone that I build never do. 5/12 is low also if the width is to small.
I know you said the main rood is a 3/12, but is there any gables facing the front of the house the same direction as the front roof, garage maybe? If so sometimes we match the same pitch, or just make it steeper to give some height.
You have many options, but posting a picture would help a lot.
Sorry to be awol - rain was crazy last few days.So here's basically what I'm planning:I think I'm going to go with 6/12 and see what it looks like...Also this area (revelstoke) is a major snow belt (last year was 500cms) So 2/10 rafters on 16 etc.Oh and the rule of 4s as I see it if you build in a dimension of 4 you minimize waste in a big way.
Edited 8/30/2008 5:17 pm by ripperathome
Your 6/12 looks good. My suggestion would be to draw your entire elevation to scale. It will only take you a few minutes...an hour at the most. If you were proficient at the free Sketch up Program, you could do it all in 3d in a few minutes.
The thing that is missing in your mockup is the overhangs. They will have a significant impact on the overall presentation.
I couldn't tell if you're going to bring your porch over the steps, but I would. And like Blue says, keep the overhangs matching the house. The trick will be to keep the fascia at the same level, if the pitches differ. A little planning should take care of that. The roof is not a multi-pitch issue, but a california valley. This should be easy, as there is no true valley or valley rafters to cut.
Frame your gable, then level back and put your ridge in back to the sheathing. Use a straight edge to mark where the rafters plane in on the sheathing, and snap lines on both sides. Intall your valley sleepers, holding them back from the line to the point where they plane in along their top edge. Then mark layout following the existing layout of the gable rafters. The bottoms are cut level, with the saw set at the angle of the existing house roof.
Here's a pic - this is a hip, not a gable, but the valley idea is the same
View ImageView Image “Good work costs much more than poor imitation or factory product” – Charles GreeneCaliforniaRemodelingContractor.com
I just noticed that I didn't get the fascias lined up. I don't know why they aren't. There's another lesson in there somewhere.Heres a different view.
and the framing.
Level fascias. I learned a few things.
Jim, To correct the fascia height in Chief find the height of the fascia on the main roff via the roof dialog box (dbl click the roof). Use the fascia height from the main roof to enter the fascia height on the dormer roofs. Be sure to set the radio button to the parameter you want to keep. be sure to check the roof pitch before you close the box, the numbers jump around if you adjust one parameter and not use the radio buttons to select what you want to keep.
Johnhad a revelation in roofing in CA.
ETA whoops! nevermind, I see you figured it out. That's what I get for posting before reading all the material.
Edited 8/30/2008 8:45 pm ET by john7g
Here ya go ripperathome.After giving your house a moment's thought, I decided that it would be a good challenge for me to figure out if I knew how to import your pic, then resize and practice a couple of Chief Skills that I've recently learned. I failed at figuring out how to resize properly, but I mucked my way through. I did figure out a couple things, so my practice wasn't wasted.
Wow - Thanks for all the help gentlemen. Jim in the amount of time it took you to produce the Chief image, I managed this in sketch-up (I got frustrated and checked the web). First time using it so I think if I kept at it I could produce some ok stuff. I'm still looking for a mac software CAD program that can hold a candle to Chief A. Anyone know of one?Jim is that a 6/12 pitch on your image?Thanks Huck - that's kind of what I had in mind, with the sleepers on the existing sheeting. For sure overhangs will be equal to and on the same plane as the existing - that's almost the whole reason for the new entrance, plus a little dry space wiggle room for wrangling the rug rats out the door. I won't go all the way to the stairs - I think running the entrance that far (12' away from the wall) and would be out of proportion - the whole house is only 30' wide/48' long. Thanks again - off to buy material before the long weekend shuts me down.
Yes, the porch is drawn with the 6/12.
I just drew this real quick in Sketchup. No where near as good as Jim's, but I think the measurements are close.Joe Carola
Nice! That shows how fast things can be done once you master the programs.
I'm wondering if I can copy a picture and put it into the free version of sketchup.Joe Carola
Yes, you can, Joe.
Go to [File] [Import] and when the select file dialog box opens under file types select .jpg or which ever file format your picture is in. Find your picture file and then before hitting [Open] look at the radio buttons on the right beneath the preview and select which fits your needs. I've not mastered the Match Photo tricks yet but I think Katz did an aricle in FHB using this method a while back. SU help ought to be able to get you moving on it, though.
John,
Thank you, You are the man!!!
One more question. Once I get it onto the screen, is there any way to get the actual dimensions to scale on the picture?
Joe Carola
Edited 8/30/2008 9:44 pm ET by Framer
You're welcome, Joe.
What I've done is use the tape tool to set out string lines to a known dimension of something I see on the photo like a door height or width & then stretch the photo using the scale tool to get what I want.
I was screwing around one night and broke down the Randall Brothers trim .pdf catalog and then imported the individual pages to SU that had close to scale drawings of their trim and then traced the pieces and made my own component catalogue. It's close enough to get the point across.
OOOOHHHH. Good idea.View Image
If you want, e-mail me and I'll send you the file. It's about 2.5meg. Maybe Randall Bros supplies near you?
Thanks for the offer, but I don't need mouldings. I need some other stuff. But I can obtain it in that fashion fairly easy. It'll keep things in proportion without me having to calculate. Thanks for the idear.View Image
Wow
Love how my question has morphed into an all out design competition!Keep it up guys, the more reference I have, the easier the job will be.Here's what I've done in the last couple of hours - beams are up and I'll lift up the rafters tomorrow. We'll see if the live version lives up to the digital world...Oh and can someone tell me how I can post pics so the image appears in the message area, not as a little yellow thingy... txs
can someone tell me how I can post pics so the image appears in the message area, not as a little yellow thingy...
http://forums.taunton.com/tp-breaktime/messages?msg=84420.85View Image
Now I'm starting to have fun. Here's another idea for you. It's all John's fault for teaching me how to draw from pictures on sketchup........;-)
Joe Carola
don't blame me for your curiosity. LOL
You're still the man. You gave me a new toy to play with.
Joe Carola
if you've got dimensions of the whole house you might as well post them too. DW and the kids are sleeping I've got a gin & tonic to work thru before i crash.
Really - I just cracked a Kokanee so we'll so what comes out in the wash.The house is an apple box:3/12 pitch
27.5' wide
48' long. 2' overhang (horizontal plane - doesn't follow the rafter pitch)I doubt we would go with the barrel entry - I'm going to faux timber frame it and plant on differentl timber accents to kind of marry it to our market and neighbourhood - ski town.The deck will be replaced in the spring - so go nuts if you're up for it. We plan on spanning the entire length of that wall (hence the sliders hanging in the wind)...Have fun
Heres your final versions using the proper dimensions of your house. I was off a couple feet on the scaling when I scaled it using the door as my known factor. I picked up a few more skills and re-inforced a couple that I had already known so I probably got more benefit from this than you did. Enjoy!
Thanks Jim - looks great. I should have it framed today. I'll post a pic. Now if I can just get shingles and grass done this quick...
I was playing around with the lanscape buttons. I learned a few things again today. Up to now, I haven't been able to find a plant, much less plant one! Anyways, I did a crash course on landscaping and you now have to plant some palm tree and poplars. You also have a nice fence without a gate. Gates are overrated.
Looking good JimCan you fellas check my math for me - this is what I've figured and it's out (too long) by about 4"...Ok
Total Span = 64"
Projection = 24"
1/2 span = 32"
Ridge beam dimension: 3/4"6/12 roof = 1.25 ratioSo my hypotenuse should be 40" (not including projection) and my total rise should be 24"... I did the math the long way and used those # for my first rafter and not even close (out by 4").... (I deI did the math with a construction master and it said 35 3/4" for line length. Anyone help me out?EDIT: 20 minutes laterSorry - my mistake I forgot to square root my 6/12 ratio. All good.
Edited 8/31/2008 4:37 pm by ripperathome
I don't have a construction calc handy but I do remember a little bit about the geometry of your roof.Your run is half the span so: 32" = 2' 8" = 2.67 units. Each unit is 6" rise.2.67 x 6 = (12 + 4) = 16" So, your total rise is 16" plus your heel. Assuming a 4" heel, your ridge height is 20" less the drop caused by your ridge...which is about 1/4" give or take a few hairs. I don't know where you got 24" from...Your length of the rafter would be 2.67 units times the unit length. Since my framing square doesn't have the tables, I'll do it from memory. I believe that the unit length for a 6/12 is 13.42" per foot of run. Multiply 13.42" x 2.67 and that is the length of your rafter. Add 2 more units for the projection (13.42 x 2) and you'll have your total theoretical length. Don't forget to subtract for 1/2 the thickness of your ridge.
Your rafter should be 35-3/8". Your rise will be 15-13/16" plus the H.A.P. cut.
I thought the span was 114" in your first post. What happened?Joe Carola
Thanks - got it figured. Sorry typo with the total span - should be 112 (64 + 48 projection). What's a HAP cut?
HAP = Height Above (top) Plate when you cut the birdsmouths of the rafters. You adjust this to align your fascias or when using differnt sized rafters.
As John said, it's the height above plate. Many things to do with that. One thing is if you want the exact rise to the top of the ridge, you need that HAP height.Joe Carola
Sure, you can copy a pic and import it into Google SU (Free) and then use it as the basis of a drawing. Just be sure to click the "use as image" option. A straight-on elevation view of a building can be pasted as an image onto a vertical plane surface of any size, then stretched to fit, then the whole thing scaled.
To do the Photo Match routine (available in the free version) you need to have a photo that is shot to show the recommended perspective view. That means a shot looking at a building's corner, with the two adjacent elevations receding away to the corner's R and L.
The Go-2-School video tutorials are a great free online resource for learning all this stuff.
Jim's antics with Chief are giving me an itch. Maybe I'll stick up a liquor store and buy me a copy of the software.
View Image
"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
You would be great combining SU with CA.
I think theres a way to isolate each part and view it. I couldn't find it but I did find a dbx that shows the ridge and some buttons to manipulate it.
Who's your friend?