Making Your Own Door Or Window Headers
Some contractors prefer to build their own door and
window headers, and these guys have been doing this for years. It seems
like more people do this on the East Coast and even in the Midwest but
it is rarely seen on the West Coast of the United States.
As an alternative to buying a 4 x 6, you can nail two 2 x 6 ‘s together, with a piece of 3/8" plywood, in between them and this will work fine as an equivalent for your new door or window header.
I know what you're thinking, a 2 x 6 is an inch an inch and a half thick and if I nailed two of them together, that would equal 3 inches. Wouldn't I need a piece of half inch plywood, to create a 3 1/2 inch door or window header?
That might work sometimes, but every time I do it, my new window header seems to be 1/8 of an inch bigger and that means that it will either need to stick out on the outside or on the inside, creating problems, for the finish carpenter, drywaller or the stucco and siding crews
There is one problem though, if you're building a new house or using plans that were approved by an architect, engineer or even your local building department. I would advise you to contact every one of them to make sure that you can actually do this.
They might specify certain sized lumber for each individual window and door header and you shouldn't stray from this.
Always ask first, if you are working with approved building plans, to find out what you can and can't do.