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I’m building an ICF house and need help with the design of the steel framed roof.
Steel framing is not common in my area. The structual engineers I’ve spoken with are not interested in designing a roof structure for residential. In fact I had to deal with an engineer 160 miles from here to get a basic design for the floor (to have 4″ of concrete on main level). I ended up redesigning his design, which he approved.
Butler Mfg. has a re-roofing division that plans to look at the plans to determine if they may be interested in the design and supply of the steel.
Does anyone have an idea of another manufacturer who might consider designing the structure if I purchase materials from them?
My second question is does anyone know where I can go for a wood to steel conversion chart? I have the arch’s design for wood stick framing, but I will need help converting to steel.
Thank you.
Linda
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There are many wood roof truss manufacturers that are now turning to making steel trusses as a sideline. As far as I know, there is no such thing as a "conversion chart". Steel is an entirely different animal than wood.
Try asking local truss manufacturers. They may be able to at least get you steered in the right direction.
*I saw one of those steel trusses the other day - pretty nifty - light guage "c" sections and tubes - apparently all fit in the same jigs as wood trusses are built in. I'm surprised I haven't seen anything published about them.
*Linda....what part of the country are you in? We do steel design all the time. Shoot me an e-mail if you want to talk furhter. I dont think this is the forum for this kind on detail.Dave
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Creature
Why not share the steel info. here? We hardly get to use 'real' wood anymore anyway so what's a little steel along with the plastic, foam, vinyl, aluminum, particle board, f/g, cellulose. . .
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Patrick:
I was referring to the business end of the deal, not the acutal design stuff, sorry to sound confusing. If Linda can give some more details on what she is doing I will be happy to share it here. I got the impression that she was having problems finding a structural to do design work. We do it for people all over the country, and I dont feel it appropriate to be soliciting business here, although I guess I just did it so, sorry guys.
Dave
*As Bill Conner noticed, there hasn't been a lot of publicity about steel trusses. That's because they are so new, I suppose. They've just been introduced in the past 3-5 years. They may or may not fit in the same jigging as wood trusses, depending on the brand of truss steel used, and the brand/type of truss equipment used. My 15 year tenure in the truss industry ended yesterday, and I never got to see a set of steel trusses built. Maybe I'll get to see some down the road...........
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Dave,
I am not offended at all. I'm very anxious to get help with the roof. I have a basic roof outline, but no structural design. Might be interesting and fun to go through a design right here.
My house is ICF with poured concrete floors over steel. I have three major sets of 10/39 beams and three minor sets of 10/30's and 10/22's. I used 8", 16 guage c channels--welded in place between the flanges. The longest span is 15' and I used bracing at mid points. Now I'll pour a 4" floating concrete floor. I think this was a bit overkill, but that's the only way I'm comfortable.
The outside edge of the joist is cut into a row of block into which I've poured concrete.
The house is basically 97x50 plus garage. The garage is 48x33. I believe the widest span in the house is 28'with a vaulted ceiling. Some of the ceilings do not vault. At present there is an exterior covered porch that spans 40'. I think this was a design error and I may need to add an extra column. This would be unsightly and I would rather not do it.
The roof pitch is a 5/12. The house has a four ft. overhang. I'm planning a standing seam roof and not sure whether to use a deck or perlins.
What questions did I miss? I'm not even sure where to start. What is the best way to secure it to a concrete wall? Should I be looking at red or galvanized?
Is this too much to discuss on this forum?
Thanks to all you guys for your interest and willingness to help.
Linda
P. S. I can e-mail an Auto Cad Lt. drawing to anyone who would like it. Might make discussions easier to follow.
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Linda
On the question of the standing seam roof, if you mean raised rib 'galvalume', go with purlins, the major cost saving with this type of roof(besides its longevity) is in the elimination of materials & labour for roof decking.There are many colours available. I've done them in Red, Slate Blue, Brown & Black, but prefer the two lighter colours myself. 6/12 is the recommended lowest pitch for steel roofing. That's a major overhang,does it double as a porch? LOL
-Patrick
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Excuse my ignorance, but what are 10/39 beams, etc.?
*Patrick, At this point Butler's roof (if I can end up using their panels) is a Pittsburg double-lock seam installed on perlins, not decking. I understand the savings--unless the name Butler eats it up. If I have to use a snap-lock system, wouldn't a deck with tar paper be necessary for moisture control???The 10/39 beams in the floor represents the height and strength of the beams.I'm still looking for help on the design of the structure itself. I e-mailed Dave (Creature) directly. I'm hopeful he'll be interested in helping with the structural design.Thanks.Linda
*10/39 beam is a steel I beam that roughly measures 10 inches in height and weighs 39 pounds per foot. It is usually written as W10 x 39.As far as going with the Butler I believe it will be more trouble as you mentioned vaulted and unvaluted areas inside. There are several good steel truss manufacturers but I cannot recall their names I will try and get that information today. The steel trusses are going to be quite a bit more than wood trusses.
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Linda
I'm not familiar with Butler, Pittsburgh double lock, or snap lock systems so maybe I'd better butt out.
-Patrick
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Linda;
We're building a masonry and steel solar home here in Va.Our roof will be supported by "steel web joists".These are used almost exclusively in commercial structures.
What we did was salvage 18" deep web joists from a demolition site for about 2 cents a pound.That turned out to be 75 units for about $400.The depth of the units determine the span and these units were engineered to span anywhere from 10 feet to a maximum of 30 feet.Since each joist is welded up using 5 separate but continuous lengths of steel all we did was cut the web joist to the span we needed,weld on the supports,and then weld to a grouted steel base plate placed on the top of our wall.
" Generic " steel web joists are engineeredas a rule of thumb using the depth as the determining factor of span.The less depth the shorter the span.
Our problem with these "massive" joist was that we had to raise the wall to raise our ceiling height.But our free labor and salvaged block corrected this problem.
If you go this route and salvage these units you may be able to find some with lesser depths.Since most web joists are commercially used you can be assured that thier lenght was engineered.
By the way,at the start of this project we could not find a web joist manufacturer that would give us info without an engineered design from an engineer.I called sveral engineers locally and told them that I was going to draw up the plans,build the house,and be completely responsible for the outcome.All I needed from them was occasional advice and a thier approved stamp whenever the building department required it.Several engineers accepted and one was hired at $400.I was surprized and grateful.
Good Luck!
Don L
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I'm building an ICF house and need help with the design of the steel framed roof.
Steel framing is not common in my area. The structual engineers I've spoken with are not interested in designing a roof structure for residential. In fact I had to deal with an engineer 160 miles from here to get a basic design for the floor (to have 4" of concrete on main level). I ended up redesigning his design, which he approved.
Butler Mfg. has a re-roofing division that plans to look at the plans to determine if they may be interested in the design and supply of the steel.
Does anyone have an idea of another manufacturer who might consider designing the structure if I purchase materials from them?
My second question is does anyone know where I can go for a wood to steel conversion chart? I have the arch's design for wood stick framing, but I will need help converting to steel.
Thank you.
Linda