The Forestry Forum is sponsored in part by:

iDRY Vacuum Kilns


Forestry Forum
Sponsored by:


TimberKing Sawmills



Toll Free 1-800-582-0470

LogRite Tools



Norwood Industries Inc.




Your source for Portable Sawmills, Edgers, Resaws, Sharpeners, Setters, Bandsaw Blades and Sawmill Parts

EZ Boardwalk Sawmills. More Saw For Less Money!

STIHLDealers.com sponsored by Northeast STIHL


Woodland Sawmills

Peterson Swingmills

 KASCO SharpTech WoodMaxx Blades

Turbosawmill

Sawmill Exchange

Michigan Firewood, your BRUTE FORCE Authorized Dealer

Baker Products

ECHO-Bearcat

iDRY Wood Lumber Vacuum Drying for everyon

Nyle Kiln Dry Systems

Chainsawr, The Worlds Largest Inventory of Chainsaw Parts





Author Topic: Is a hip roof a timber framing nightmare?  (Read 47618 times)

0 Members and 1 Guest are viewing this topic.

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Is a hip roof a timber framing nightmare?
« on: February 18, 2012, 10:50:43 PM »
Hi All,

I'll keep this short and sweet- it's my first post and I don't want to get labelled blabby until at least my third.

I'm planning on erecting a square frame (29'x29') over a set of existing adobe walls as a restoration project.  My plan was to put a simple metal hip roof on it, but after running that idea by my brother (who has slightly more experience than my "next-to-none") and his friend (who is a professional tf), the consensus was that a hip roof is, at best, gonna be really difficult for anyone and probably impossible for a newbie like myself.  But I really want a hip roof- it'll make the overhang I need on all sides so much easier....

So I feel the need to increase my sample size- I'd like to hear the opinions from the wizened framers out there: to hip or not to hip?  Any information is greatly appreciated!

cheers,
randy

Offline Rooster

  • Senior Member
  • ****
  • Posts: 688
  • Location: Lake Mills, by way of Fort Atkinson, WI
  • Gender: Male
  • Tools are extensions of ourselves... share a tool.
    • Share Post
    • Photobucket image storage account
Re: Is a hip roof a timber framing nightmare?
« Reply #1 on: February 18, 2012, 10:59:39 PM »
Welcome!

You are talking about a roof with 4 hips, coming up from the outside corners of the building, and all coming together at the peak (center of the building), creating 4 seperate roof planes...not a Gambreled roof system...right?

Rooster
"We talk about creating millions of "shovel ready" jobs, for a society that doesn't really encourage anybody to pick up a shovel." 
Mike Rowe

"Old barns are a reminder of when I was young,
       and new barns are a reminder that I am not so young."
                          Rooster

Offline Dave VH

  • Senior Member
  • ****
  • Posts: 284
  • Age: 41
  • Location: southwestern michigan
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #2 on: February 19, 2012, 04:50:00 PM »
I've framed hundreds of homes, and many many of them were handcut hips.  Now I haven't done a lot of timber framing yet, I don't think that it would be that hard, I think that the principles are the same.  But maybe that's my inexperience talking.
I cut it twice and it's still too short

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #3 on: February 20, 2012, 12:22:02 AM »
Hi Rooster, thanks for the words of welcome.

And yes, we're talking about the simplest hip roof you can picture; 4 hips, no gambrel.

Dave, it's apparently cutting the joints at the compound angles where the hip rafters meet the other structural roof members that scares my other timber framing consults.  One of them even suggested I cut joints for all of the simple part of the roof and stick-frame the hips.

cheers,
randy

Offline Migal

  • Senior Member
  • ****
  • Posts: 594
  • Age: 59
  • Location: East Texas
  • Gender: Male
  • I'm new! But Old as Dirt!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #4 on: February 20, 2012, 12:36:04 AM »
its all in the angle with computer imagery soft ware it should be a piece of cake ask you local truss company for the angles you need to do.
Stihl learning and picked up my Log Master LM2 Cat 34hp 02 21 12! 230MF+ the toys that go with it! MS361 MS271 Stihl PB500 Echo 48" LogRite 16ft Bass Tracker Pro' Abua Garcia 5600 bait caster, Wood working equipment' Lake Lot never enough time! oh don't forget the fridge with ale! Loving Wife Rebeca

Offline witterbound

  • Senior Member
  • ****
  • Posts: 443
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #5 on: February 20, 2012, 09:20:34 AM »
I believe your friends are correct.  A hip timberframe roof is goning to be next to impossible for a newbie w/o building experience.  Draw it on skectup, and see how difficult it is to design.  It can be done, just very difficult for a newbie.

Offline tomsteve

  • Full Member x2
  • ***
  • Posts: 126
  • Location: west branch, mi.
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #6 on: February 20, 2012, 11:15:28 AM »
i have only done one timber framed roof , but have done a LOT of framing. mcmansions with some really cut up roofs. hips, valleys, lay ons..all the good stuff. framing them was difficult for me to understand until i got with a very experienced carpenter that taught me how to read and use a speed square. it's all geometry and can get really confusing. theres a lot of measuring and layout before a cut is even made with stick built rafters/ roofs.
any chance you could hire yer brothers friend to give ya some help with it?


http://www.blocklayer.com/roof/roofeng.aspx


this might confuse ya, but could help


http://www.johnsonlevel.com/files/manuals/RAS-1.pdf

this explains some on a spped square.

Offline Rooster

  • Senior Member
  • ****
  • Posts: 688
  • Location: Lake Mills, by way of Fort Atkinson, WI
  • Gender: Male
  • Tools are extensions of ourselves... share a tool.
    • Share Post
    • Photobucket image storage account
Re: Is a hip roof a timber framing nightmare?
« Reply #7 on: February 20, 2012, 02:09:21 PM »
Randy,

If you are going to build on the outside of existing walls, what type of framing will keep the roof from the thrusting the walls/corner posts apart?

Do you have some photos of the project?

Rooster
"We talk about creating millions of "shovel ready" jobs, for a society that doesn't really encourage anybody to pick up a shovel." 
Mike Rowe

"Old barns are a reminder of when I was young,
       and new barns are a reminder that I am not so young."
                          Rooster

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #8 on: February 20, 2012, 05:04:28 PM »
Thanks for the links, TomSteve- they are a bit beyond my pay grade at the moment, but I'll have to get to the point where I understand that stuff at some point, so it's good to have the references in hand.

Rooster, I'm a little confused by your question (and I'm building inside of existing walls- really wonky, leaning adobe walls, which is why I don't want to put a roof load on them).  My understanding is that the joinery and construction details (beam size, etc.) in the bents and connecting members of the lower frame, coupled with design elements of the roof itself, are what keeps the roof forces from pushing the walls apart.  I figure I may be misinterpreting your question, though.

randy

Offline Red Pill

  • Full Member x2
  • ***
  • Posts: 108
  • Age: 62
  • Location: Fort Worth
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #9 on: February 20, 2012, 05:29:17 PM »
It may be that your first post was confusing, since you said you were building over existing adobe walls.

Offline Stumpkin

  • Full Member
  • **
  • Posts: 74
  • Age: 58
  • Location: Grafton IL
  • Gender: Male
  • Not all who wander are lost.
    • Share Post
    • The Edgeworks
Re: Is a hip roof a timber framing nightmare?
« Reply #10 on: February 21, 2012, 11:55:24 AM »
Hey, it's not that hard to do a simple hip rafter and pockets or housings for the tops of the jack rafters. I would do a developed drawing using the common roof pitch to determine the hip and jack rafter angles. Drawing the angles out always helps to visualize the roof planes and how they interact.
This is a Developed Drawing for a 9/12 common pitch hip.
 

 
I would not want to do a purlin roof system into hips because purlins where they intersect with a hip or valley are longer on bottom than they are on top and it would be very hard to assemble.
Tom  edgewrks@gtec.com
"Do we know what we're doing and why?"
"No"
"Do we care?"
"We'll work it all out as we go along. Let our practice form our doctrine, thus assuring precise theoretical coherence."      Ed Abbey

Offline Thehardway

  • Senior Member
  • ****
  • Posts: 934
  • Location: Virginia
  • Gender: Male
  • Doin' it the hard way!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #11 on: February 21, 2012, 03:55:03 PM »
I think you can do whatever you put your mind to and spend enough time on.  If hip is what you want, don't settle for less because of a lack of knowledge or experience.  "Experience" tends to come easy when you lack knowledge, it is just not always kind or economical.

I like to think outside the box. I would differ with the prior poster.

 I don't see a hip being as diffcult done with trusses and purlins or principle rafters and purlins as it would be with common rafters and jack rafters.  There are a lot fewer joints to cut.

Many of the old frames left the purlins proud on the rafters and didn't join them directly into the sides of the rafters or trusses.  This method is simple, uses less joinery and is very interesting visually from the underside if left exposed.

Fancy joinery is not always advisable or most durable in a TF.  Keep it simple.

The way I see it, you mill or hew 4 - 5 sided hip rafters at the correct angle for your hips and then lay your purlins on them and leave them proud useing very basic purlin cleats under each one to secure them.  Omit the jack rafters. No complicated joinery work is needed, just a very simple M&T on the under side of the cleat to hold everything in place.  I'll see if I can dig up a picture of this for you. You can even go with a layer of common rafters over these if so desired.  TF rule of thumb is the best joint is the simplest and strongest joint to get the job done.

since your building is square you can have all this intersect into a central post.  Think of it as a four way Kingpost truss with purlins and a mid span principle rafter.


Norwood LM2000 24HP w/28' bed, Hudson Oscar 18" 32' bed, Woodmaster 718 planer,  Kubota L185D, Stihl 029, Husqvarna 550XP

Offline Dave VH

  • Senior Member
  • ****
  • Posts: 284
  • Age: 41
  • Location: southwestern michigan
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #12 on: February 21, 2012, 10:06:29 PM »
for me, it's easiest to do with a speed square, and a framing square, but a newbie can pick up a construction master calculator and figure it out with the instructions.
I cut it twice and it's still too short

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #13 on: February 22, 2012, 03:01:36 AM »
Hardway,

I like the box you think outside of, and I'm exactly of the same mind about joinery, simple is best but it has to get the job done properly.  After my relatively intense first framing experience, my forearms and hands were so wrecked that I vowed to keep joints as simple a they could be to avoid unnecessary wear on my poor aging bones.

I'd love to see a picture of what you're suggesting; I think I get the general idea, but I'm not quite certain.  Essentially my picture of what you're talking about is a roof that's all hips and no ridge (a pyramid, basically), purlins laid proud across all of the hip rafters with cleats, no jack rafters at all.

Do you think some version of this would work with a ridge beam and 4 hips?  I'd like to leave some more headroom for a loft.

cheers,
randy

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #14 on: February 22, 2012, 03:20:02 AM »
Dave,

I'm thinking it's going to be all pencil, paper, and re-learning my high school trig.  It's the only thing I can trust not to misguide me 'cause as you point out, I have no clue how to use a speed square properly (except as a straight edge)- I'd always be afraid I was screwing something up.

randy

Offline Dave VH

  • Senior Member
  • ****
  • Posts: 284
  • Age: 41
  • Location: southwestern michigan
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #15 on: February 22, 2012, 05:11:11 AM »
moorerp,
  I've framed homes well over the 10,000 sq ft mark, and I've never taken trig.  It's really not that hard to learn a speed square.  It could be taught in 10 min if someone is paying attention.  I don't know where you live, if you're close to southern Mi, I could teach you in person.  If you're not going to build for a while, I could teach you at the pig roast in August.  If you get desperate, maybe my wife can show me how to upload a video.  Let me know if I can help.  feel free to send me a IM,
I cut it twice and it's still too short

Offline Thehardway

  • Senior Member
  • ****
  • Posts: 934
  • Location: Virginia
  • Gender: Male
  • Doin' it the hard way!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #16 on: February 22, 2012, 08:56:53 AM »
Randy,

Do a quick Google image search on the term "Purlin Cleat" and you should find a picture on Builder Bill's site which shows a picture of exactly what I am talking about.  I will try to draw it and post when I get time but this will give you a good mental image of the purlin cleat and how it attaches to the rafter with a simple 3 sided mortice and tenon which is super easy to cut. (much easier than a 4 sided mortice)

As for the hands and forearms:

1.  You likely need a proper mallet.  Using the right mallet weight and material will soften vibration and impact on the hands and will also drive your chisel better.
2.  You may need a different chisel or a keener edge.  Different types of woods require different angles on the chisel for efficient cutting
3.  After a week of steady chisel work your forearms will swell like balloons and the pain will begin to subside

What kind of hammer and chisel set up are you using?

I see no reason you couldn't use a ridge purlin.  This will of course complicate some of the geometry as it will not all be symmetrical if your base building is square rather than rectangular but your roof frame is rectangular.

Perhaps a very useful learning exercise for you would be to build a model of the project using some scaled timbers made out of 2X material on a table saw and then do a mock up of the joinery and the angles.  It is cheap, gives you a great grasp on the concept you are trying to build, and you can pull a full cut list from it when you are done.  The model will make a great doll house if you have any kids in your life.  There are some great pictures of TF model on this site you should check out.

The confidence and reference this scale model will give you and the reference it will serve as, is much better than just having a drawing. Especially if you are trying to engage family and friends in the effort.  Being able to see how things all fit together is very important and ensures you don't end up with an oops moment at raising.

Have fun with it!

Cheers, Bob
Norwood LM2000 24HP w/28' bed, Hudson Oscar 18" 32' bed, Woodmaster 718 planer,  Kubota L185D, Stihl 029, Husqvarna 550XP

Offline canopy

  • Full Member x2
  • ***
  • Posts: 205
  • Location: Thailand
  • Gender: Male
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #17 on: February 24, 2012, 08:01:18 PM »
I did a hip roof as my first TF (see avatar) but would not recommend doing it without someone experienced. There is enough that can go wrong on a timber frame without adding that complexity on top of it. It could be the straw that breaks the camels back so to speak. There were times I would describe layouts which seems such a simple thing as a nightmare, but a finished hip rafter is an amazing thing to see. There are a couple ways of approaching layouts for a hip roof. A traditional way is to reference the Hawkindale angle tables which you need to study how to use. I did this and found it very time consuming, but it works. My advice would be to use google sketchup all the way: draw your whole frame including hips and jacks then grab the angles. If you are already very good at sketchup this will be a snap. And if you aren't, this could take a few weeks to get to this level and afterwards you'll get dividends as sketchup can be useful for countless things in the future.

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Re: Is a hip roof a timber framing nightmare?
« Reply #18 on: February 25, 2012, 01:36:31 AM »
Thanks for the input Canopy- yours was probably the first example I looked at for timber framed hip roof; it's quite a beautiful thing.

I think I've decided to go with hips of some kind after a lot of backing and forthing, mostly because I just can't see any other way to get the overhang I'm going to need that's as simple and elegant (design-wise, not joint-cutting-wise) as a standard hip roof.  I figure if I take my time while I'm doing it, and plan the thing out completely using Sketchup (which I'm only OK with, but I'm very excited to have just discovered TFRubies- thanks Clark!), then I should be able to pull it off, especially is use some of  Bob's simplification ideas.

I'll send pictures once I get the thing drawn up so that everyone can rub their hands over their faces and point how many of my design elements are (to be charitable...) unwise.

Thanks for all the help so far, everybody-

cheers,
randy

Offline moorerp

  • member
  • *
  • Posts: 31
  • I'm new!
    • Share Post
Update
« Reply #19 on: March 18, 2012, 05:26:18 PM »
Howdy,

After all this good discussion, I've decided to suck it up and go with simple hip roof.  I ordered an Alpha roofing protractor (from Jim, as it turns out) off of ebay to help with the layout of the nightmare angles of the hips and the jack rafters (as few of the latter as I can get away with).

thanks for all of the help!  I'll post progress notes.

cheers,
randy


Share via delicious Share via digg Share via facebook Share via linkedin Share via pinterest Share via reddit Share via stumble Share via tumblr Share via twitter

xx
timber framing a octagonal 8:12 roof

Started by plbnyn on Timber Framing/Log construction

13 Replies
4229 Views
Last post March 18, 2008, 11:26:32 PM
by plbnyn
xx
Reinforced Timber Framing / Mock Timber Framing?

Started by Stuart Caruk on Timber Framing/Log construction

22 Replies
4522 Views
Last post January 14, 2015, 08:47:15 PM
by Gumneck
xx
Swiss and German Roof Framing

Started by D L Bahler on Timber Framing/Log construction

25 Replies
843 Views
Last post March 25, 2020, 11:19:58 PM
by D L Bahler
xx
Gable roof framing, what size rafter?

Started by sbishop on Timber Framing/Log construction

7 Replies
6742 Views
Last post July 11, 2008, 07:33:05 AM
by Don P
 


Powered by EzPortal