timber frame header span ?

[SIGNGUY]

Just wondering if someone could tell me the max span of a 6'' x 6'' x 18' hemlock beam? It would be supporting the roof. Just wonder what the max distance I can space the 6'' x 6'' x 6.5' uprights.
Thanks in advance!

[tuckermtn]

by saying it is supporting the roof, do you mean it is a plate with rafters sitting on it?

[rookie]

I wouldn't go more than 4 ft., unless you put 45 degree braces off your uprights. then i think you could go six feet. But i'm not timber frame expert, just a carpenter that generaly builds with conventional lumber.

[SIGNGUY]

"by saying it is supporting the roof, do you mean it is a plate with rafters sitting on it? "


Yes i did mean wall plate with rafters siting on it....Sorry I was not more discriptive. I do plan to use 45 degree supports on each upright also...
Thanks!
Origanal Question: Just wondering if someone could tell me the max span of a 6'' x 6'' x 18' hemlock beam? It would be supporting the roof. Just wonder what the max distance I can space the 6'' x 6'' x 6.5' uprights.

Thanks in advance!

[GeneralStark]

"by saying it is supporting the roof, do you mean it is a plate with rafters sitting on it? "


Yes i did mean wall plate with rafters siting on it....Sorry I was not more discriptive. I do plan to use 45 degree supports on each upright also...
Thanks!
Origanal Question: Just wondering if someone could tell me the max span of a 6'' x 6'' x 18' hemlock beam? It would be supporting the roof. Just wonder what the max distance I can space the 6'' x 6'' x 6.5' uprights.

Thanks in advance!

Kind of tough to say without more details about the frame, but I assume you are not using bents and are just putting up two load bearing walls with rafters on the plates. Also depends on pitch of roof for snow loading effect, but I can get back to you shortly after I look at my reference manual.

[village idiot]

I'd love to cough up some suggestions, but I'm really not sure about how the building will be built. How big are you going to make it? Will the 18 ft include any overhang? (are you really spanning say 16ft? What else will these be joined to? What about the other dimension of the top plate? How will they be attached? I think when you say "45 degree supports" you are talking about knee braces. I'm not sure knee braces add any strength to the plate, or let you span any farther... use smaller wood...), but they will certainly make the building less likely to fall down.

I guess that isn't too helpful.

[SIGNGUY]

what I am building is what i guess you may call a modified timber frame.....The building is going to be 18'x14' with a one foot over hang. Built with 6 by 6's. Fastened with timber bolt lags. Roof rafters will be 2x6's with 1'' pine for sheathing and corrigated metal roofing. No sure of the pitch yet. I just was trying to figure out how far I could space the 6x6 uprights.
Thanks for all the feedback!

[rookie]

well the dimensions make it a little easier, your gonna want to put in 4 posts per wall right? If you used 3 ( 9 foot span) on your long wll that would be to much, in my opinion. and then 3 on your shorter walls will be fine cause the gable end tkes no weight. more or less. assuming that your long walls are your eaves and short walls are gables. I have a beam sizing program on my computer i could run through when i get time.

[noreast maple]

Four and ahalf feet apart and you wont have to worry as long as the top plate is of same size.

[rookie]

I think when you say "45 degree supports" you are talking about knee braces. I'm not sure knee braces add any strength to the plate, or let you span any farther... use smaller wood...), but they will certainly make the building less likely to fall down.

I guess that isn't too helpful.


Well I'm certainly not an expert in timber framing, but the angle supports help serve 2 purposes. they help the building from racking ( falling in one direction or the other) and they also help deflect some of the load off the beam and direct the weight to the post.

[sap retreiver]

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