Wood – Using extra plywood as stringer for window boards

hurricane-panelsplywood

Trying to size out some window boards for a hurricane. It's actually two questions but the stringer is the main one.

I have a section of windows that is roughly 14' x 4'6". Given a sheet of plywood at 8' x 4', I was thinking of laying one full sheet horizontally, and then stringing together 1' worth making the sheet 8' x 5'. Then stringing in the remaining length of windows from a second shortened sheet that is also strung with an extra 1'.

My first question is, can I string these pieces together with whatever leftover plywood that I have? Or do I need to get something thicker / stronger?

My second question is, does the above strategy seem structurally ok for boarding against a hurricane?

I imagine something like this… where """" indicates stringers.

+---------------------------"-------------+
|                           "             |
|                           "             |
|                           "             |
|                           "             |
"""""""""""""""""""""""""""""""""""""""""""
|                           "             |
+---------------------------"-------------+

Sorry if I'm butchering up any terms / ideas!

Best Answer

If those stringers are unsupported by an underlying structure such as a substantial mullion, it would allow unacceptable flexion at the joint under high wind conditions IMO. Even with a solid wood stringer you might have trouble over that long horizontal span.

Might I suggest that you use your idea but with the plywood in a vertical orientation? I know this would double the number of sheets required to 4 (5 to join with plywood "stringers"), but it would be much stronger this way. Also, the smaller pieces would be much easier to handle and install, and easier to store when there is no hurricane threat. 5 sheets is still way cheaper than a new window that size, you could use the leftover for other smaller windows.