Replies

1. 
   Hokuto | Aug 24, 2011 09:26am | #1

   Disclaimer: I'm very much an amateur.

   I also love the Arts and Crafts (Craftsman) architecture style. Here in Japan, exposed rafter tails and gable-end purlins are common (part of the Asian influence on Frank L. Wright and others in that period). Whatever material you use has to be structurally sound since it is continuous with the interior rafters and purlins. For sake of economy I would probably use PT wood and just be sure to get the highest quality of SPF, then allow the boards to dry well before installation. Some boards may twist as they dry, but not all. Cull out the good ones and use them for the exposed parts. Then use a good anti-rot preservative stain on them before installation, and then again after installation (and periodically after that). My assumption is that since the rafter tails and purlins are exposed, they will have an easier time of drying out between rains, and less chance of rot or of being eaten by termites compared to those hidden behind soffits where moisture remains. (And PT wood is resistant to rot and insects anyway.)

   Here are a few photos I took yesterday of homes in the neighborhood; I would guess that a majority of traditional style homes here have open soffits with exposed rafter tails and purlins, and most are built of Japanese cedar (sugi, Cryptomeria japonica), and they aren't pressure treated to begin with.

   http://s27.photobucket.com/albums/c197/Peregrinor/ww/2010_housework/P8237990SPw1.jpg

   http://s27.photobucket.com/albums/c197/Peregrinor/ww/2010_housework/P8238003SPw1.jpg

   http://s27.photobucket.com/albums/c197/Peregrinor/ww/2010_housework/P8237997SPw1.jpg

   http://i27.photobucket.com/albums/c197/Peregrinor/ww/2010_housework/P8237979SPw1.jpg

   As for the roof decking material, what's wrong with exterior grade or PT plywood (painted or stained)? If you don't like the bare look of plywood, you could cut out sections of WRC lattice and affix that between the rafter tails/purlins as well, although I don't know how it would be viewed from the canons of Craftsman architecture..

2. 
   Bing187 | Aug 24, 2011 07:18pm | #2

   I've done a couple.... There may be an easier way to do it, but I've gone with using a piece of cedar 2x8 or 10, cut to an attractive shape. Rough the shape with a jigsaw, finish with a router and pattern bit. Strictly a dummy rafter tail, so the part that shows is cedar; the rest is conventional. I've done the roof deck a couple different ways, one being ac plywood with the smooth side down, another (Pain in the neck, but more attractive) was making the cedar dummy rafters a little narrower so they sat 1/4" lower than the commons, and used v-groove or beaded pine on the part that showed.

   Bing

3. 
   Piffin | Aug 28, 2011 12:06pm | #3

   Fir and Hemlock are common for the rafters here. This is a maritime climate ( read wet) and with proper design and detailing, those rafter tails never see enough water to rot.

   For sheathing/decking, traditional was 2x6T&G. There is a multitude of other ways to detail it though. For instance, you can cut the rafters overhanging parts notched 3/4" deep and use 3/4" T&G v groove or beaded edge facing down, and then run plywood or advantec over it and right on up to the ridge. Some of the detailing wil depend on your local structural requirements and seismic if in Cali

1. 
   andy8156 | Aug 28, 2011 12:37pm | #4

   Re

   I am starting to formulate a plan and I believe it will involve stopping the common rafters at the wall and then scabbing separate tails onto the common rafters.  Since I am going to be puttting cedar shingles and bevel siding on the walls I think cedar tails would look quite good.

1. 
   Piffin | Aug 28, 2011 04:21pm | #6

   Cedar would certainly look good, but it can be expensive and when you scab it on you need extra length back up in....

2. 
   justbugme | Sep 01, 2011 08:37am | #8

   Cedar!

   Cedar is the way to go. Dummy tails attached as in a comment above. Don't kid yourself though, cedar will crack and split in time if not treated nice. As with all exposed wood, it will need maintenance. But I think is worth the expense on a craftsman style home.

3. 
   wallyo | Sep 08, 2011 11:11am | #12

   I would not use cedar or PT for the rafter tails.  Just keep it simple use doug fir for rafters and  extend them keeping them exposed. If you are using trusses  comunicate to the truss plant let them know you are going to keep them exposed and if they can do anything to  help on the appearance side (harder in some cases since the wood is cut by computer).  Once they are ten feet plus up in the air small flaws can not be noticed anyway.  Cedar is hard to find dry will twist and splinter also it does not hold nails too well,  when fence building I use cedar fence boards and posts with fir rails, lasts a lot longer. You may want the top cord of the truss to be a 2x6 if you want a beefier tail.

   For the sheathing pine or fir was common, three inch to 6 inch wide, either t&g or ship lap.  When it is t&g it is usually v grooved, ship lapped it is flat. I use the boards where exposed and fill the unexposed in with ply or wafer board which means using 3/4 sheathing on the whole roof (if asphalt shingle).  On the gable ends if it is standard gable, roof I extend the boards at least 2 feet inward so they are cantalevered. (extending inward  rafer over the gable on to the overhang).

   More inportant is how are you going to vent it.  If needed I can get you some photos of a continious eave vent I came up with.

1. 
   andy8156 | Sep 08, 2011 11:32am | #13

   RE

   I would very much like to see any photos of a continuous vent you have used.  I have some ideas how to do it but nothing concrete, yet.  On the subject of using Douglas Fir for the tails, I would like to leave it a natural color as I am going to be using cedar siding with a clear stain applied.  I wonder how fir would look finished that way.

1. 
   wallyo | Sep 09, 2011 10:23am | #14

   Andy

   I can get some photos and post them tonight  or tomarrow for you.  As to the clear stained fir and cedar, since both tend to range in color from red to a sap yellow the two should be very similar.  You could always have a bit  of tint added to one gallon of stain to use say on the rafter tails if ithey need to be darker, or the other way around.

4. 
   DoRight | Aug 28, 2011 02:59pm | #5

   Don't worrry about materials

   Don't worry about the material, the eaves and particularly the underside of the eaves are the most weather protected part of your exterior!  You can buy trusses and just leave the tails exposed.  No special materials required.  I would certainly not use PT.  It does not take stain the same as other wood and those pressure holes are ugly and why pay for it..  Just no need.  After all do you use pressure treated siding?  Why not?  Same for the decking.  Just use clear plywood and stain it as you like.  Not as pretty as TG, but works fine.  Seen it many times.  Or use 1" boards.  Plain them down to 5/8 if you like, but if your sheathing is 5/8 and you use 3/4 boards at the eaves you will not notice the transition under asphalt shingles (I have done it).  Ease the edge of teh last board if you like.  

1. 
   Piffin | Aug 28, 2011 04:25pm | #7

   I would not use PT either, but "pressure holes"?????

   Incised fir for PT is used on the west coast, but here in the east, it looks like any other SYPine.

1. 
   DoRight | Sep 01, 2011 07:55pm | #9

   What do you call them?

   What do you call those slits or holes?  But, no matter, you apparantly are just bright enough to figure out what was being said.  LOL.

1. 
   Piffin | Sep 01, 2011 09:36pm | #10

   Well, Incised is how it is treated. Incisores are used to do it, so I uess I'd have to call them teeth marks

5. 
   JohnWalker | Sep 08, 2011 01:13am | #11

   Prime all six sides

   I am looking at the same proposition and have decided to apply fake tails. Painted wood trim only stays painted if you prime all six sides before installation.

   For what its worth I have decided to use standard kiln dried framing lumber and dip it in slightly thinned oil based primer. The top coats will be 100% acrylic latex. My reasoning is slightly thinned oil based primer has superior pentration and wont peel. Period. And yes acrylic latex is compatible.

   John

6. 
   gRUovudZb7 | Sep 12, 2011 03:25pm | #15

   Rafter tails

   Hi:

   Being a GC and having designed and built Craftsman Bungalows I would like to congradulate you on your choice of style.

   The suggestions from the other members are good and accurate. One thing to consider is whether you are going to have a deck ceiling or not. If you are planning on using the idea of trusses with extended legs be aware that you will end up with "skinny" looking legs and you will not have adequate room for your required insulation.

   If you want a deck ceiling (applied over your rafters) you will be putting the insulation over the boards (we use XPS most often) and you will have to add "Faux" rafter tails (cedar works well and looks good). I tend to use cedar T&G on the top side of the tails with metal vent channels. Works well.

   Bob

1. 
   andy8156 | Sep 12, 2011 05:40pm | #17

   Re

   Bob,

   I had planned on using faux rafter tails thereby avoiding the skinny rafter tail look.  I really haven't thought much about the insulation situation, yet, but I should have room over the ceiling joists above living space to add what I need.  I plan on using T&G decking over the rafters only in the eave area.

7. 
   andy8156 | Sep 12, 2011 05:34pm | #16

   RE

   Thanks, wallyo, for those photos.  It always helps to visualize a concept that way.  It looks like what you effectively created was a mini-boxed in soffit in which to house the eave vents.  It looks very slick and well-built.  My thoughts on the eave vent was to add vertical blocking in between the tails and install the vents in a vertical orientation.   I haven't drawn it out on "paper" yet, so I have yet to work out the details.