How to Build Header Beams

[AnthonyW]

I'm not sure which board this belongs, so I thought I would put it here under processing since it also applies to kiln construction as well as any other building construction. I am simultaneously looking to build a storage shed (with a 4' wide doorway), shed for the mill (12' open span for the on load side), and solar kiln (8' or 10' opening for the doors in the rear).

I know when you frame a door, you have king stud married to a jack stud on either side, and the jack stud supports the header. For the standard doors of a house, the header consists of a married 2x6s. That would alludes to the requirement for a span up to 36" wide requiring a pair of 2x6s for the header.

My question is what are the requirements for the size of the jack studs and header boards to span:
4 feet?
6 feet?
8 feet?
10 feet?
12 feet?

[Hilltop366]

I looked and can't find my chart right now (It is for spruce/pine/fur) , but I will add that you will need to know your wood species before you can pick the minimum header (aka lintel) size.

The jack stud is usually the same as the header but once beyond a specific span the jack should be doubled according to the Canadian building code.

I got my info from the canadian building code book at the local library.

Not the direct answer you were looking for but it may help you on your way.

[LeeB]

http://www.duluthmn.gov/building_safety/general/Header%20Tables%20-%202007%20MN%20Residential%20Code.pdf.

See if this helps you.

[AnthonyW]

http://www.duluthmn.gov/building_safety/general/Header%20Tables%20-%202007%20MN%20Residential%20Code.pdf.

See if this helps you.

If I was to use store bought lumber, it will be spruce or fir.

That's a pretty good reference. It looks like I would qualify for the first section Roof and Ceiling (as there is no second floor). I'm a little confused as to the building width. The width is measured perpendicular to the ridge, but the span will be bridging a gap parallel to the ridge.

For the 10'-11" span, they are calling for 4-2x12s for the header and two jack studs. That would make a beam 7" thick, so the studs would be 2x8s?

[LeeB]

I can't help you anymore than what I have already given you. I just did a search and found that.  :D I'm none to savvy on the issue either. I was just curious about the issue. Surely someone else will be along shortly.

[Planman1954]

I would use two 2x12s with 3/4" plywood in the middle. Use construction adhesive and nail extensively. That will span (using pine) up to 11' well.

[beenthere]

Anthony
Be sure to figure in your snow loads and they will likely be dependent on the pitch of the roof.
Sounds like your wide door beam will be supporting the roof trusses or rafters.

Depth of your beam is an important dimension to gain strength.

[Larry]

For standard walk door headers 2 X 12's work well as that way you don't have to add any additional cripples between the header and the top plate.  Saves a lot of time. 

Over 6' I liked composite beams made up like a sandwich with a plywood or steel core.  Granted you can do it with standard framing lumber and probably meet code, but it will sag over time.  I have switched from the sandwich to LVL's, again due to a labor savings.

[AnthonyW]

Anthony
Be sure to figure in your snow loads and they will likely be dependent on the pitch of the roof.
Sounds like your wide door beam will be supporting the roof trusses or rafters.

Depth of your beam is an important dimension to gain strength.

The wide door beam will be supporting the roof trusses/rafters in at least two cases (kiln and mill shed). The storage shed may or may not depending on the orientation and location.

The sheds will probably be metal roofing which tends to shed snow fairly well. The storage shed will either be single pitch 6/12 or steeper. The mill shed will be dual slope/off center ridge. The back will be 6' from the ground, and the front 8-10' (extra clearance for a tractor or the like for loading). The solar kiln will look like a solar kiln, I don't suspect much snow load on it. hahaha.

My basement has 3 2x8s for the center beam with 8' between columns. For the 10' and 12' spans, would 3 2x12 interlaced with 3/4 plywood sitting on a jack stud of married 2x8s do the trick?

[jueston]

My basement has 3 2x8s for the center beam with 8' between columns. For the 10' and 12' spans, would 3 2x12 interlaced with 3/4 plywood sitting on a jack stud of married 2x8s do the trick?

that's 2 jack studs on each side

[red oaks lumber]

metal roofs still hold snow. we have 18" on the roofs, been there for 2 weeks now. when in doubt go with an lvl header. yes its more money but, how much is putting a new building back up?

[AnthonyW]

metal roofs still hold snow. we have 18" on the roofs, been there for 2 weeks now. when in doubt go with an lvl header. yes its more money but, how much is putting a new building back up?

No one carries LVLs. They are all special order by contractors only.  >:( What about building one? From what I have seen they just appear to be a 2x4 cut in half (2x2) with a 3/4 groove in the middle and a pirce of OSB cut and glued in place.

What about exposure? How do LVLs stand up to the elements? Wouldn't be an issue with the kiln, just worried about the mill shed. My current shed (open sided) covers it from most of the rain, snow and elements, but not 100% like the kiln or enclosed shed.

[beenthere]

No one carries LVLs. They are all special order by contractors only.  >:( What about building one? From what I have seen they just appear to be a 2x4 cut in half (2x2) with a 3/4 groove in the middle and a pirce of OSB cut and glued in place.

LVL stands for laminated veneer lumber, so is different from the joists that you describe being 2x2 and OSB.

Both have engineering values that can be obtained if you have some good ideas what the loads will be. 

[AnthonyW]

LVL stands for laminated veneer lumber, so is different from the joists that you describe being 2x2 and OSB.

Both have engineering values that can be obtained if you have some good ideas what the loads will be.

Yep. You're right. I was thinking/describing the wooden I-Beams they are now using for floor joists. I will have to work up a rough idea of the roof weight and then look up snow weights and add them in.

Edit: I was just at the GP website and their LVL and wooden I-beams are not recommended for use outdoors in open structures. Hip/Ridge Beams, Door/Window Headers, Garage Door headers.

[red oaks lumber]

iv'e used several lvls for headers and they all have been sided over, even the ones just under the eves.

[woodmills1]

not much help on headers, but I have done a few load bearing beams

lived in a cape and wanted to open two rooms front to back, the second floor was 2x6 floor joists and I wanted a flush ceiling.  Built temp support walls and took out the studs, cut the floor joist to fit a hand nailed beam of 5 2x6 with no plywood or steel, used joist hangers to nail the second floor joists.  It was 13 foot 6 inch worked fine even with a water bed in the second floor bedroom.


built a 12 by 12 side porch and wanted a cathedral roof with no collar ties
3 2x8's used for the ridge beam took all the snow load, both ends of the ridge were supported by 6x6 posts to footings

did the same for my 16 by 20 garage addition using 3 laminated hemlock 1 3/4 by 10 supported by solid post to the concrete, with footings below.  needed the height to allow a vertical flip for boards at the table saw

[Holmes]

I would go with planmans idea or something similar.  Quite often I have seen 3  2 x 12s with 1/2" plywood between each 2x12 glued and nailed together for a long header  [up to 12'] on new houses, supported by 2x6 jacks on each end.  More than 12' you should look into beams.
I believe there was a thread about putting a continuous  layer of flashing between the sandwich layers, and the header would not even sag.

[jueston]

if glue lams are out and you want to think outside the box you could look into Flitch beams, you would have to do some engineering(or pay a professional) but a flitch beam is a steal plate with a wood member on each side of it, the wood and steel work well together and create a very strong beam.

a google search should get you some basic info on it.

[AnthonyW]

I am leaning towards Planman's idea. It also just occurred to me, what a single 5 1/2" x 12" x 10' long solid white pine beam, green of course since I have a sawmill (duh on me!)?

[GeneWengert-WoodDoc]

I do believe that two 2x12s will do as well with or without plywood.  Also, often you do not get extra strength if you glue them together unless there are knots or weak spots in the individual pieces.  The idea of gluing or frequent nailing is that the weakness in one area of a beam, like from a knot, is shared by the solid wood strength in the other.  Note that laminated beams have the glue line running from edge to edge and not vertically.

If you purchase the 2x12s, they must be perfectly flat, as wood adhesives do not bridge a gap between the pieces very well, except for a few adhesives.  Also, use an adhesive designed for carrying a load...pva would not be a good choice.  Also, commercial lumber often had a contaminated surface, from a gluing standpoint, so lightly sand the surface before gluing to get the desired strength.  As you might be aware, some building inspectors will not approve a homemade beam as they are not sure of its strength.  A commercial truss plant may be able to give you the strength numbers from their computer programs and thereby make everyone happy and safe.

[Planman1954]

If you do a solid beam without lamination, chances are it will eventually sag in the middle. The double 2x12 beam with plywood glued between will serve the purpose the best. As Gene said, adhesive is not totally necessary, and maybe not even the plywood. But for myself, I like the extra strength of the plywood to keep the 2x12s in their place. I would still nail it very well though.

[AnthonyW]

Silly question. What is so special about an I-joist, that I could not make one my self? Take a 2x4x10', rip in half, cut a groove and install a piece of 8" wide 1/2" thick OSB. The glue the whole shebang together. Do that twice and I would have two I-joists 10' long. If I-joists are stronger than solid lumber, why would I go this way?

Could I skip the ripping step and cut two grooves in each 2x4x10' and produce a single I-joist with two webs? How would the strength of the single joist compare to the pair of I-joists?

I could do this for the kiln, but I think I stuck with the mill shed.

[beenthere]

Tony
You might find that the 2x2's used in the I-joists are structurally visually graded for strength and the I-joist is engineered for a certain load.
But nothing says you cannot do what you suggest.

[GeneWengert-WoodDoc]

With an I-beam, nearly 100% of the strength is determined by the top and bottom pieces.  So, as mentioned, they are exceptionally high in strength.  Also,some I-beams will have the center web with lots of holes or voids...that reduces weight, meaning the beam can carry more external weight.  In fact, the ultimate I-beam is a wood truss...lots of air space and critical strength of the top and bottom pieces.

[Peter Drouin]

I went 24' with a 10x10 red oak, no sag  ;D