My sister clued me in on a seller of stock plans called Robinson Design a few years ago. They are somewhere in western Canada, and sell into both the Canadian and U.S. markets.
We are looking at maybe doing one of their models for someone here, and the design has a handsome eyebrow-roof dormer.
I emailed one of their reps through their site, to ask some things about the structure, but did not get a reply yet. We are trying to gage the complexity of the whole thing.
Here is a view from outside, showing the general shape of the ‘brow.
And here, from inside, you can see how the ceiling is tracking the shape on the underside.
Here is a pic taken from a different house, done with the same plan scheme. You can readily see here how the clearspan space looks.
This tells me it is done with engineered trusses. Or at least that is the only thing I can think of to handle the clearspan roof/ceiling structure.
The views shown here are screencaps taken from a quick Sketchup model I did to try to visualize things. The trusspac shown has a 4-pitch at the top of the arch, and a 6-pitch at the bottom of the fillets. The span is 32 feet.
The pic inside the room confirms for me that the curved header to pick up the end bearings is post-supported at intermediate points so that its depth doesn’t have to be too much.
Has anyone seen a frame done with trusses like this?
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Gene,
There was an article in FHB, about twenty-some years ago, on this framing detail, or it may have been a bowed eyebrow window.
I guess you'll have to buy a short term subscription to the on-line FHB archives if you want to look at it. I haven't done that yet so I can't say how well it might serve you.
It would depend on the interior details. Is the ceiling flat inside? Does it follow the curve? Each way would create a different frame. Bob's next test date: 12/10/07
It would depend on the interior details. Is the ceiling flat inside? Does it follow the curve? Each way would create a different frame.
Duh...yup!
Edited 6/6/2008 2:10 am by Hudson Valley Carpenter
This is the link to the document refered to by Hudson Valley Carpenter http://www.taunton.com/finehomebuilding/hot-to/articles/framing-bow-window-eyebrow-compound-curves-build-roof.aspx?langtype=1033&ac=fp
I don't suppose I'm allowed to post the article so here is a picture of how they did it:View Image
...and the article is from March 1, 1988. So almost exactly 20 years ago. Good memory!
Good memory!
Unreliable memory, lucky guess. I appreciate you looking it up for us.
That's wicked awsome, go for it when you find out how. I believe you can get a 14 day trial for the web archives, might be time to accept
there's no need to reinvent the wrench
Where's this one at? Pretty nice views out the window. Or is that protective film and the other side is a brick wall?
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I don't have the book handy... but I'm pretty sure in Will Holiday's book "A Roof Cutter's Secrets" he details how to do exactly what you are trying to do.
I don't have the book handy... but I'm pretty sure in Will Holiday's book "A Roof Cutter's Secrets" he details how to do exactly what you are trying to do.
It does... that was to be my suggestion as well.View Image
Good luck finding a truss company to make those work out. Most have trouble on simple stuff, at least around here any way.
Took a little time to flesh out how the whole thing might work, and here is a view with part of the lid off.
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Here is a q for you drywall finish wizards. How much of a premium would you expect for the hanging and taping of the ceiling underneath? I am presuming it will take a couple layers of 1/4 flexrock.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Edited 6/8/2008 5:38 pm ET by Gene_Davis
Edited 6/8/2008 5:40 pm ET by Gene_Davis
Can't answer your drywall question but i do have two comments to make about the trusses. Maybe you're already aware of this but i figure i'd point it out anyways.
1. your bottom chord will be sloped from one end to the other. If the entire span is within the same room that would be fine. But if the span is divided into several rooms, some of these will have sloped ceiling and will need to be leveled.
2. On a normal wall, your trusses above the window would rest above a sizeable lintel or beam. In your case, you will need a curved beam or several straight segments with columns in between your windows. You show fwo in your drawing. A third might be required in the centre if you want to use straight beam segments.
Chucky, the space below is one loft and the ceiling vault above a first floor room below, and there are no walls, save for the chase wall you can see that hugs the wall, that rise up and intersect.
One big swooped ceiling, going right straight on across, one side of the house to the other.
Here is a photo looking across the loft, in a house built with this feature. Note how the cantilevered front edge of the loft is given the same shape as the ceiling, in a different plane.
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The beam that spans the room over the windows, and picks up the truss bearings, is supported at two intermediate points by posts between the windows. The beam is a two- or three-pack of LVLs, pattern-cut to the curve, and pieced. It need not be continuous across the posts.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
This is a spec house?
Nope. It's for someone who likes curves. I found a pic album of something from the same series being done. Here are three pics.
Note how the header is simply done with straights, then thicknesses of 2x (and even notched ones) boost up to the specified bearing height at each truss point.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
I like those pictures of the framing.
will holladay's book "a roof cutters secrets" give step by step details on how to do those types of eyebrows, in at least a couple variations.
without a doubt will's book is my favorite reference for roof cutting/framing. there are many ways to layout for construction purposes, but the way will does it is exactly the way i do it. we both apprenticed at about the same time (he was a couple of years ahead of me) in the same area, so we had the same teachers/methods.
it may not translate well to the right coast. california uber alles.
i think stick framed structural rafters is a better way to do this job, but then i am a builder not a designer. if i were going to try to design trusses for this i would certainly study will's book first.
http://www.amazon.com/Roof-Cutters-Secrets-Framing-Custom/dp/1928580149