Instaling windows on existing steel building

[jjohnsonElknewbie]

Hey guys, I have a 30'x50' pole barn with steel siding. The build is from the late 70s and they used 2"x6" nailers. I want to install windows on the SE corner to add some natural light to our gym. I have the windows already bought and am looking for tips on the best way to approach. The building has spray foam insulation, and I already removed the foam from the sections that are getting the windows.

QUESTIONS:

• What is the best way to cut the steel for the openings? Taking it off really isn't an option since the sheets are around 20' long, nailed in, and spray foamed from floor to ceiling.
• Can I use a nailer as the header and screw the top of the window box directly to it, or should I add separate header boards?
• Etc...
• All tips are appreciated in advance!

 

[BuckRut]

You are going to want to frame in all new window framing because you want the framing on end to the metal. You won't be able to properly secure the window with the fin. They are made to be broken off if needed and secure the window with screws through the jamb. Install J trim and seal as usual.

 

[sconnieVLP]

I like using a grinder with a metal cutting wheel for steel siding. You can use offset tin snips, but it’s going to be a pain for any sizable cuts and even more so with the siding already mounted. The cut will likely look a little “burnt”, but you can hide it in the J-trim around the exterior.

 

[displacedtexan]

A nibbler would be best. But I wouldn't go buy one. Snips will be fine. I'd probably use an abrasive wheel on a grinder because I buy those in bulk.

You don't need a header. You do need enough nailers that are tied into the framing to properly support the window.

Be sure to use j trim, properly.

 

[jjohnsonElknewbie]

Thank you very much!

 

[BuckRut]

A nibbler would be best. But I wouldn't go buy one. Snips will be fine. I'd probably use an abrasive wheel on a grinder because I buy those in bulk.

You don't need a header. You do need enough nailers that are tied into the framing to properly support the window.

Be sure to use j trim, properly.

What are you going to secure your J trim to with no header?

 

[displacedtexan]

What are you going to secure your J trim to with no header?

A nailer.

A header is structural support to provide a load path for weight above. Cutting into a wall on the side of a shop has no load.

 

[jjohnsonElknewbie]

Here is a pic of one of the install locations. That middle nailer will need to be braced prior to cutting out a section in the space the window will occupy.

 

[BuckRut]

A nailer.

A header is structural support to provide a load path for weight above. Cutting into a wall on the side of a shop has no load.

You may not need a traditional boxed "header" but you had definitely put something somewhat rigid (like a 2x4 turned on its side not flat to the tin) across the top and bottom otherwise the wind loads are going to make the panels move which will damage whatever seal you make between the window and the metal trim over time.

 

[jjohnsonElknewbie]

You may not need a traditional boxed "header" but you had definitely put something somewhat rigid (like a 2x4 turned on its side not flat to the tin) across the top and bottom otherwise the wind loads are going to make the panels move which will damage whatever seal you make between the window and the metal trim over time.

So I’m this scenario, do you recommend running 2x4s vertically on edge on either side of the window and including a window header and footer with 2x4 bracing for the lower nailer where a chunk will be cut out?

I could run a 2x4 on the back of the top nailer at the bottom to provide additional purchase for window frame fasteners.

 

[jjohnsonElknewbie]

Finally, as far as window orientation, is it best to center the window on a steel rib such that the outside edges lay against steel flats?

 

[BuckRut]

So I’m this scenario, do you recommend running 2x4s vertically on edge on either side of the window and including a window header and footer with 2x4 bracing for the lower nailer where a chunk will be cut out?

I could run a 2x4 on the back of the top nailer at the bottom to provide additional purchase for window frame fasteners.

Correct. You can notch the vertical members so they sit flush with the nailer or add nailers to the framing members. Mostly just remember that the window is not a structural member. If you think the opening is flimsy or moves when you push/pull on it before the window is installed it will be the same way after the window is in.

Finally, as far as window orientation, is it best to center the window on a steel rib such that the outside edges lay against steel flats?

Structurally and for sealing purposes it doesn't matter much but the vertical cuts will be significantly easier if they are on the flats.

 

[jjohnsonElknewbie]

Correct. You can notch the vertical members so they sit flush with the nailer or add nailers to the framing members. Mostly just remember that the window is not a structural member. If you think the opening is flimsy or moves when you push/pull on it before the window is installed it will be the same way after the window is in.

Structurally and for sealing purposes it doesn't matter much but the vertical cuts will be significantly easier if they are on the flats.

Thank you and exactly what I needed, I appreciate it.

 

[displacedtexan]

You may not need a traditional boxed "header" but you had definitely put something somewhat rigid (like a 2x4 turned on its side not flat to the tin) across the top and bottom otherwise the wind loads are going to make the panels move which will damage whatever seal you make between the window and the metal trim over time.

Sufficient bracing is still not a header.

 

[stanginthe11s]

cut the hole with snips or a nibbler. if you use a cutoff wheel the edges will rust quick. then, once the hole is cut, put the window in from the inside and frame it. a 2x4 or 2x6 top and bottom spanning from main uprights it typical, then box the window. go outside, slip your trim in between the panel and window and send screws through. be sure to cut the trim correctly to prevent water from coming in or pooling. go back inside and spray new foam.

 

[bryan79]

A diamond wheel on grinder works great instead of cutoff wheel. More expensive but last a long time and not much spark. Hit the edges with some clear acrylic in a spray can to prevent rust

 

[Pinewood]

I would frame a traditional rough opening that spans north/south across the existing 2x6's. Notch the vertical framing members over the lateral 2x6's, notch as necessary. Connect them with A35 framing angles and structural screws. Tie the whole wall structure together that way. After framing cut metal out using the frame as a guide. Screw the metal siding back to the window wood framing, install window.

 

[EastHumboldt]

You can also use a circular saw with metal cutting blade. It’s basically a thin grinder wheel with a saw arbor. If you go this route, put some masking tape on the outside to protect the paint from the foot of the saw.

 

[dubllung4]

Prebuild your window boxes with 2x6s on edge and attach through the existing nailers. That way your jambs will be in the same plane as your 4x6 columns. Use 2x4s to fill the voids between nailers. Make sure you run your J channel past the sides, and leave the steel up 3/8" from the top of the J channel.

RR Buildings on Youtube has great videos for this. You definitely don't want a rib to land on the edge of the window so plan accordingly.

 

[stanginthe11s]

don't over think it, there really isn't much that goes into windows on a building, it's not a house. technically, the sheets alone can support a standard window but any movement over time tends to loosen the screw holes. also, if you can get the window between those girts shown, then you can just fasten to those and be done.
nothing you're doing is structural, the only time you need to add anything is when you remove or cut a girt. if you only cut one girt, then you only need to replace one. many ways to do it, and if you ever plan on sheeting inside then you may as well frame it out now. if you spent the extra money to get closed cell foam, then wind load is something I wouldn't worry about as that is structural, but I don't expect you did given the extra cost.

also, one tool none of us mentioned to cut sheets is a jigsaw. a fine blade works perfect and everyone owns a jigsaw lol. go cut some holes and let us know how you made out. remember, keep it simple. pick whatever way you feel comfortable with and enjoy your new window.

this is a quick technical add for others that may read this or for guys who are used to building houses.​