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agordon8233

How do I calculate how large of a header to have for a load bearing wall with an opening of 7 feet. I have the space to double up or even tripple up beams to add strength. Currently there are two 2x10s with 2 2x4 (laying on side) on top. I need more floor to bottom of header space and this 14 inch header seem like over kill for a 7 foot span.

thanks

Debra

2 inches for every foot of length sounds good to me but I looked up a sight that says:

Quote:

Calculating header size is complicated. You have to take into account: (1) the length of the window or door opening; (2) the combined weight of the floors, walls and roofs above; (3) the building width; (4) the snow load in the area; (5) whether it’s a bearing wall (where joists, trusses and rafters rest) or a non-bearing wall (to which joists, trusses and rafters run parallel); (6) whether it’s an exterior or interior bearing wall; and (7) what species of wood you’re working with.

The 2000 International Building Code book contains two full pages of mind-numbing charts for calculating proper header sizes in different situations. Fig. B shows the maximum allowable spans for different size headers in just one situation. As you’d expect, the deeper the header, the longer the distance it can span. But trust me, you don’t want to wade into all the technicalities. There’s no simple formula. My advice is this:

Have an engineer or architect calculate the required header size for your window and door openings.

When in doubt, build a double 2x12 header sandwich like we explain next. In all but the most bizarre situations, they’ll easily carry the weight for 4-ft. wide window and door openings and, in most situations, be code compliant for openings up to 6 ft. wide—a common patio door width.

FIG. B
HEADER SIZE MAXIMUM SPAN NUMBER OF TRIMMERS

Double 2x6 4 ft., 0 in. One

Double 2x8 5 ft., 0 in. Two

Double 2x10 6 ft., 2 in. Two

Double 2x12 7 ft., 1 in. Two

From The Family Handyman by Reader's Digesthttp://www.rd.com/familyhandyman/content/18202/

But you need to go with what your local code demands as well so pay an expert to calculate it for you not a housewife with computer access in Oklahoma

canuk

debby nailed it (pun:D ) ... nobody from here can tell what loads are there.

To say the existing header is overkill .... maybe .... chances are it's that size for a reason. There could be a second storey and the header is under a bathroom for all we know from here ... good advice given is to consult with an engineer.

You might be able to use an LVL or similar engineered beam ... but that would have to be determined by a professional.

Just my 2 cents.:)

agordon8233

Thax for the input. Looks like what is there is correct and I need to work around it.