Letter Re: Securing Windows With Plywood The Fast And Easy Way

I’ve been researching ways to secure windows in a SHTF scenario and it seems that one of the best ways to do this is by screwing pre-cut sheets of plywood to the window frame.  This will take many screws and it will leave screw holes in your window frame if/when it comes time to take down the plywood.  It also takes precious time to put a lot of screws in even with a powered screwdriver and depending on the size of the window, you might need several people to hold the plywood in place while you put the screws in.

The French cleat method involves securing a strip of wood with a 45 degree bevel to the wall, and then securing an opposing beveled strip on the back the object you want to hang.  This is often used to hang cabinets and is very strong.  If you add French cleats to to top (and to the bottom if you want it really strong) of your plywood and windows, one person should be able to hang each piece of plywood very quickly.  If you build it into the existing trim, provided it is strong enough wood, it will be almost undetectable unless you are looking specifically for it. 

When the SHTF, just grab your plywood with the opposing 45 degree bevel and hang it.  Maybe put one of two screws in when you have time if it makes you feel better. This system should save a lot of time and window frames for people that need to G.O.O.D. or hunker down when a natural disaster such as a hurricane or tornado is approaching and they want to save their windows.  It is also a good addition for security since the connection is very strong, but you’ll still have to add screws since the plywood can be literally lifted off the French cleat and set aside, providing access to the window. 

You can also add another French cleat to the bottom of the plywood and window for additional strength and just have screws on the sides. This method can also be used with any material you can securely attach a cleat to if you want to use something other than plywood. 

1/4″ metal window covers with a welded cleat would be able to stop most rounds and therefore offer the most security.  Since the connection is so strong, you might be able to attach a few sandbags to your plywood if needed.  I do not know exactly how much weight this will hold (most sites just say “very heavy”) and it depends on the materials you use anyway so use common sense if you decide to use this method. – Jonathan J.

JWR Replies: The weight of sheet steel adds up in hurry. Here is a useful quote from my novel Patriots:

Originally, Dan had suggested either one-inch thick mild plate steel, or half-inch thick hardened steel to go over the windows and doors. That was before he realized how much they would weigh. When he got back to Chicago, he consulted one of his books of engineering tables and found the formula for figuring the weight of plate steel: Length (in inches) x width (inches) x thickness (inches) x .2560 = weight (pounds)

Thus, for instance, a 1″ thick piece of of plate steel that measures 36″ x 36″ weighs at least 331 pounds. That is what you would need to stop .308 or .30-06 AP. Even .308 ball with a 90-degree hit will go right through 1/4″ steel plate if it isn’t hardened.

After I first posted this, Reader G.C. added this clarification: “The math presented is for a 1″ thick 36″ x 36″ plate, though most mil spec sheets will suggest that plate will weigh in between 360 and 370 lbs. (I came up with 367.56 lbs from the spec sheet I used.”

The weight of 1″ plate steel (or several stacked layers to achieve comparable thickness) requires special handling precautions. Safety first when handling plate steel, folks. Some of the following might sound slightly paranoid, but I’ve “been there, don’t that” and have accumulated a couple of little scars:

  • Get plenty of assistance.
  • Over-engineer all attachment points.
  • Be sure that everyone wears safety (steel toe) boots.
  • Don’t use flimsy or tippy supports. Use an engine hoist for pieces that weigh more than 120 pounds. Lift with youg legs, not your back.
  • Measure twice and cut once.
  • Have fire extinguishers handy.
  • If at all possible, do all your cutting and welding before you lift.
  • Keep kids and pets at a safe distance.
  • Move slowly and deliberately, and don’t lose control of a plate. Remember… acceleration: “32 feet per second…”
  • Have a cell phone close at hand. (And if you are out in the boonies beyond cellular coverage, then be extra careful.)
  • Have some bandages, a CAT, several packets of Quik-Clot (or Celox), and Betadine close at hand.
  • Put car keys in their slots so that vehicles are ready to go, if needed.
  • Most importantly: There should only be one person in charge. Thoroughly talk through the expected actions of everyone on your crew before you lift anything. (Namely: A.) Who will hold what, where, and how, and for how long, B.) Exactly what maneuvers/transitions will be used, and C.) What to do if X, Y, or Z happens.

I wish you success and safety with your project!