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Building a Post Frame Home | Window Boxes + Doors | Remington | Part 8


All right, guys, welcome back to MR Post Frame. It is too cold and snowy to be outside, so are in the garage making window boxes. I'm going to take you through, step by step on how to make a window box for a post-frame home."

Window Box Detail:

Creating a window box

So when making your window boxes, obviously, you need to know the rough opening for your windows. We are starting with all of the 36 by 60 windows. In this case, the house we're working on has seven, so we're making all those together in one batch. We've done all the cutting, and now we're going to put them together. This is for a post-frame style home. I'll show you how to tie them into the framing to carry the load over the post. A couple of things we do with our windows: If it's a 36 by 60 opening, you have to cut your top boards three inches longer to get your full 36-inch inside diameter. Another thing we do is put a three-degree slant on the bottom of our sideboards. That way, if you ever have a window failure, the water will hit your flashing, go out over your Tyvek, and down the wall. Now that we've got all our pieces cut, we're going to assemble them. We'll be screwing all these together.

Let's take you through an entire window. We have one window with a rough opening of 30 by 42. That's 30 wide by 42 tall. We'll cut the boards at 33 and 42. We'll put a three-degree slant on the bottom of this one, so we'll cut these at 43. Jake will put the three-degree bevel on them. Once we have all the pieces cut, we can screw them together. After we put them together I like to go back and check all my measurements and I also will make sure it’s completely square while installing.

Window Box Installation:

Installing window boxes on a post frame house

The next step in to install our windows. We are ready to start laying out our window boxes. We need to pull nine-inch on-center marks all the way down the side of the building so that the sides of our windows do not line up on the rib. That's very important. We're going to hook the tape on one end and mark our nine-inch on-center all the way down so we can put our window boxes in the appropriate place. We then can decide exactly where to install our windows. I measure, square, and screw them in where I want them and then I go back and cut out all the girts that are in the middle of the window opening. This same process is applied to the door boxes.

Removing girts from a door or window box

We have all our windows blocked in. I want to take time to explain how the weight is transferred to the posts. So we made that box with a three degree slant. If the window ever fails, the water can run out and over the side. The window gets installed and screwed into these girts. The blocking is for attaching trim and side metal. The girts transfer the weight over to the poles, which take it down to the foundation. If you're worried about this not working, you can also run a 2x4 screwed into your window box. As for door openings, we have a sliding door and a front door. We cut the threshold out, put insulation in, and the concrete will get poured. We do the same for the jambs, ensuring a smooth transition with no visible seams.


All right, guys, that wraps up the window and door boxes and installing them. If you have any questions, leave them in the comments. As always, we appreciate you visiting our post.

Thank you,

MR Post Frame

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