What is the Purpose of a Storm Window?

You’ve more than likely heard the term “storm window” at some point in your life.  Maybe you’ve been in a discussion with some friends or family and they’ve made reference and you’ve just smiled and nodded.

It’s a common enough item that’s discussed – but possibly not as commonly understood.  Here in this article, we’re going to give you everything that you need to know about storm windows so that you can be empowered in all your future discussions.

But before we get into the specifics on the purpose that these awesome windows provide, let’s spend a bit of time discussing what they actually are.

purpose of a storm window

What Are Storm Windows?

Storm windows are actually a secondary window that you install either on the inside or outside of your existing main window (inside or out is going to vary depending on the specific type of window that you purchase).

There are few different materials that a storm window can be manufactured out of – these include the following: glass, rigid plastic or flexible plastic sheets.

So, you can think of storm windows as being an additional layer of window that you overlay on top of whatever existing window you have.  And, these can be applied to whichever window you want on your house just so long as you are matching the measurements.

Functions of Storm Windows

Storm windows have many different functions that they perform and we’ll be sure to walk through all of this in the below.  But, if we had to summarize with one concept – it would be increasing the efficiency of your home’s windows.

Let’s take a quick look at the specifics though:


The most essential function of a storm window is to afford your windows an extra degree of insulation.  The way that this occurs is that (as mentioned above) the storm window is overlaid (either on the interior or exterior) over the existing window.

This creates multiple additional layers of protective insulation for your home.  First, there is the extra layer created by the storm window itself, whether it be glass or plastic, and the second is the air that stands present between the pane of the storm window and your home’s actual window.

Bear in mind too that using a storm window affords a fairly economical option towards accomplishing this as compared to buying new energy-efficient windows altogether.

window insulation installation process


Sound is vibration traveling through the air, right?  This being true means that an additional benefit of your storm window’s capacity to insulate is that less sound will be transferred through your window.

This goes both ways – both for sound coming into your home from the outside and also for the sounds within your home traveling out.

This is definitely a feature that you would want to consider if you live near urban centers or if you live out near highly trafficked roads or highways. Storm windows are a great way to add some peace and quiet into your home.


Now to get to the storm in a storm window.  Storm windows add an extra layer of protection to the vulnerable glass of your actual main window.

This can prevent costly repairs from having to be accomplished and give you further peace of mind.  Specifically, if you are living in an area that has a lot of volatile weather (high winds and frequent bouts of hail), this is a feature of a storm window that you would do well to consider.

Another aspect of protection is preventing would-be criminals from accessing your home.  That extra layer of protection can serve as a solid deterrent from folks with ill-intent trying to gain access to your home.


All of the above sounds like excellent features to have – you’re probably wondering what the drawbacks are.

While we wouldn’t go so far as to classify these as being outright negatives, there are definitely a few things that you should bear in mind when considering if storm windows are the right option for you.

First, interior storm windows can have issues with condensation.  Essentially, moisture can build up between the storm window and your actual window due to the flow of treated air in your home.

This can cause an obscuring effect on your windows where you cannot clearly see outside.  This effect will not be a constant and there’s a chance you may not have it all –  but it is certainly something worth considering.

Secondly, exterior storm windows can cause some difficulties in rough aesthetics.  Depending on the type of storm window you purchase, they can produce a very bulky and distracting appearance on the exterior of your home.

One way to mitigate this is by installing storm sashes that assist in blending the storm window with the overarching aesthetic style of your home and removing the clunky, industrial look that might be present if you just have the storm window alone installed.

standard double hung window sizes

Trust a Professional to Install Your Windows

Feldco has high-quality vinyl windows in many shapes and sizes to perfectly fit your home. We also have professional and experienced window installers to make sure the job is done correctly.

At Feldco, we have replaced over 1.5 million windows with the help of our factory-trained installers. We have served over 400,000 happy customers because of our award-winning and energy-efficient windows.

Lastly, we provide homeowners with great local services and showrooms so they can customize their homes with a variety of window styles and colors.

Speak with a product specialist and get a free quote today.

Share this article:


Get started with

*View our privacy policy

Or call us at 1-866-4FELDCO®
or visit one of our locations.


window privacy options

Beginner’s Guide to Installing Window Blinds

The Complete Beginner’s Guide to Installing Window Blinds Embarking on ...
remodeling after kids leave for college

Empty Nest Makeover: Redecorating After Kids Leave for College

The Empty Nest Makeover: A Guide to Redecorating After Kids ...
installing roof vents

Step-by-step Guide: Installing A Plumbing Vent Through Your Roof

Step-by-Step Guide to Installing a Plumbing Vent Through Your Roof ...
young woman cleaning her front door

How to Clean Your Entry Door

How to Clean Your Entry Door: A Step-by-Step Guide for ...
Sliding Patio Doors

Why Patio Doors Drop and How to Fix Them

Why Your Patio Door Drops & How to Fix It ...

Book Today and Save!

Over 500,000 homeowners have trusted Feldco with their windows, siding and doors. Click the button below and we’ll get started on your quote!