How to Install an Interior Storm Window

How to Install an Interior Storm Window

Did you even know there were such things as interior storm windows?

Well there are! I’ve actually used them for a few different projects.

In our last house, a 100 year old house,

we finished the attic space and I didn’t want to remove the charming original windows, but they were only single pane windows with old glass. So, to maintain all the original charm but add great insulating performance, I installed interior storm windows on all the floor height attic windows. They worked great! They also offered safety, as the original windows were old glass, but the new interior storms I installed were tempered glass. (Here is a post I wrote about that attic renovation)

In our current home,

a 1970’s that we’ve been renovating, some of the windows and all the doors needed to be replaced. (Here is the post about those changes) But most of the windows didn’t need replacing, and we didn’t want to replace them. Yes, they are original, (kind of old-ish) but I like that vintage charm. They are the original Andersen Windows pass-by sliders… I was told they were the kick-off to Andersen’s patio doors! They are double pane, but barely.

Now a days we buy double pane windows and there is special gas in-between the sealed layers.

I doubt these have any gas in-between. I think they are just 2 separate layers of glass in the sash. There is a lot of draft and cold/heat (depending on the season) that seems to come right through the glass. There is actually a lot of noise from outside that easily transfers through the windows too. If the windows were in bad condition I would have considered more strongly replacing them, but these are in really, really good condition!

My answer to make them more sound proof and more importantly, have a better insulating factor, yet still maintain the original windows, is to install interior storm windows.

We live in NW Wisconsin, where insulating from very cold winters is a must!

I was going to order all the interior storm windows in one fell swoop… but I got nervous about doing that without trying out one to be sure it was going to fit. I watched the installation video Larson’s has online, and checked with their specs… my windows and casing didn’t have quite the required clearance, due to that bottom runner on the Andersen Windows by-pass sliders. So I just ordered 1 interior storm window to start with, the smallest one… the cheapest one… just in case I had to trash it…  If it worked good, then I’d order the rest. But I sure didn’t want 14 special order interior storm windows I wouldn’t be able to use.

These interior storm windows are available HERE

So here is what I did: (read on to see if it worked on these windows!)

How to Install an Interior Storm Window

I gathered all my installation supplies and the interior storm window in the bathroom. (the tools needed are pretty simple, a cordless drill, tape measure, pencil and screw driver)

How to Install an Interior Storm Window

The roman shade in the bathroom is a top-down bottom-up. With the bottom up, it was in the way of seeing in the top of the casing, so I actually lowered the shade all the way down, that way I only had the strings to deal with… no biggie.

This style of interior storm window is super easy to install… It hangs from only the top mounting strip. So a couple of screws in the top casing is it.

How to Install an Interior Storm Window

The directions that came with the interior storm window were pretty simple. But there were a couple things I had to figure out as I went along…

How to Install an Interior Storm Window

The first thing was to pull apart the mounting strip and the trim piece that gets snapped in to hold the window.

After I marked the casing with the mounting strip held in place, I pre-drilled the holes.

How to Install an Interior Storm Window

Then I screwed in the supplied screws holding the mounting strip up. My driver in my drill is pretty short, so I couldn’t get it all the way into the groove of the mounting strip.

How to Install an Interior Storm Window

So I finished the screw with a hand held screw driver. Which is actually probably better… that way it avoided getting in too tight and stripping the hole.

Another thing that I had to figure out by dry-fitting the window in the top mounting strip…

How to Install an Interior Storm Window

is knowing which side of the window was supposed to be facing out into the room. Both sides of the interior storm window looked finished, and the installation picture didn’t show a close up of the mounting bracket well enough for me to understand.

That’s why I’m showing a close up picture, (albeit a little blurry) of the mounting bracket here.

See that part of the bracket that is rounded on the top? That’s the part that has to ‘hook’ into the mounting bracket. Trust me, I tried it the other way first… and though it fits and seems to hang… it also falls off! Fortunately I didn’t take my hands off the window before I realized it just couldn’t be right! After I took the storm window back down, I put on my glasses and realized my mistake!

Okay, so I guess it actually is kind of obvious…

How to Install an Interior Storm Window

You can see that curved part of the mounting strip that the curved part of the bracket sits in.

Hindsight is 20/20… so is my vision when I actually have my glasses on!!

In the picture below is the window hung on the mounting strip, but before the mounting strip face piece was snapped in place. (remember back at step 1 when I took the two pieces of the mounting strip apart? That’s the face piece that now has to go back on to secure the window)

How to Install an Interior Storm Window

At this point, the interior storm window was not secure. The directions are very clear, and I clearly understood once I was at this point. Without the mounting strip face piece snapped in, the window could easily be lifted off the mounting strip. But it wasn’t ready to mount yet, as I was going to have to remove the window again for the next step.

Next, in the directions are the bottom ‘stop’ pieces…

How to Install an Interior Storm Window

I inserted the little gasket pieces as the directions said, then went to place them on the window sill where they were supposed to go.

Oh yeah…

Or should I say, Uh-Oh!

How to Install an Interior Storm Window

That wasn’t going to work… hence the discrepancy in the actual window clearance and the specs for what they were supposed to be.

Because the Andersen Window bottom runner piece sticks up and out from the sill, there just wasn’t room for the supplied stops.

Would this be a problem???

How to Install an Interior Storm Window

Actually this winded up not being an issue at all!

The bottom supplied ‘stop’ piece is only there to stop the interior storm window from swinging into towards the window, and that’s what the Andersen Windows bottom runner did anyway. It stuck up just enough to provide that needed ledge to stop the storm window from going in. Perfect! Saved me a step!

How to Install an Interior Storm Window

Here is the window all done. You can see that top mounting strip face piece is snapped in and secures the window on the mounting strip.

(That part was a little tricky to be sure it was snapped on in the right groove.)

How to Install an Interior Storm Window

This picture doesn’t show it too well, but all along the interior storm window sides is a rubber gasket that provides a really good seal.

How to Install an Interior Storm Window

I am amazed at the difference! There is virtually no draft and very little noise now. Installing an interior storm window allowed me to save the original window and save money!

I’m thrilled with it, and have already ordered the other 13!

This one was just small enough that I could lift and install it myself, but for most of the other windows which are much larger than this one, my husband is going to have to get roped into giving me a hand lifting them into place.

You can find these interior storm windows HERE!

Here you can read more about the renovations we have been up to on this house:

Thanks so much for stopping by! Please feel free to follow and share this blog with your friends, as well as on Facebook, Pinterest, Flipboard, Bloglovin, YouTube and now Instagram! I appreciate you reading along.

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This post is linked at these other sites: Between Naps on the Porch, Skip to My Lou, Refresh Restyle, DIY Showoff, My Uncommon Slice of Suburbia, Worthing Court, A Stroll Thru Life

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