Milwaukee has a huge number of older homes and a huge number of older windows. In the bungalows of Bay View, the duplexes in Riverwest and the Cream City brick homes all over the city, putting plastic on the windows has been a winter thing for generations. When the wind comes off the lake in January, a sheet of shrink film can make a front room feel a world away. Consequently, it keeps the room from being drafty.
But does it work well enough to be worth doing year on year? Here’s a fairly honest assessment.
How Plastic on Windows Works
Window plastic is a very thin clear film which is applied to the window trim using double sided tape. It’s then shrunk down tight with a hair dryer. It has two functions really: it traps a layer of still air against the glass. Additionally, it stops air getting past the sash.
As per ENERGY STAR, window film covers will reduce drafts, make the house feel warmer in the winter, and reduce condensation on the glass. If the film goes right over the woodwork, it will also stop the air leaking around the window itself.
How much does it really help?
Less than most people would expect. ENERGY STAR rates plastic over windows at two out of five stars for energy savings. It also points out that window work typically has a smaller impact than air sealing and insulating the attic and basement. The City of Milwaukee’s energy program makes the same point: windows are not normally the primary source of drafts in a house.
Plastic is essentially a comfort measure. It makes the chair by the window more pleasant. It won’t turn a bad window into a good one.
Signs the Plastic Is Hiding a Bigger Problem
Milwaukee’s stock of housing is over a century old and older windows tend to fail in a fairly predictable way. Plastic won’t help if you’re seeing:
- Rot on the wood sills and sashes. It’s quite common on the original windows in a prewar house and it gets progressively worse each time the moisture freezes and thaws.
- Fog between the panes. On a double glazing unit from the 80s/90s this would mean the seal has failed and the insulating gas is out.
- Peeling paint or water stains around the frame. Peeling paint is one of the things ENERGY STAR lists as an indicator of air leaks. Water stains can be a sign that water is getting in.
- Windows either painted shut or held open with a stick. If a window’s not working then the film just seals the problem in.
- Old storm windows that rattle. There’s a loose storm window in one of the upper flats. It lets the cold right through to the window behind it.
A Note About Older Milwaukee Homes
The DOE, in its consumer guide to energy efficient windows, points out that the vast majority of homes built prior to 1978 have lead paint in them. This can be a real health hazard during renovation. A significant proportion of Milwaukee homes were built prior to 1978. If your window trim is peeling that’s another good reason to have the replacement carried out by properly trained installers. Instead of just scraping and prying at it yourself, trained installers will handle the job safely.
Plastic or Replacement? Four Questions to Ask
- Are you doing the same windows every winter?
- Is the frame solid or soft when you press on it?
- Does the window open, close and lock as it should?
- Is there any moisture or fog that you can’t wipe away?
If those answers point to a tired window then ENERGY STAR would agree. Their guide to window replacement lists single glazing, drafts, deteriorated sills and sashes, and windows that are just plain painted shut as all being indicators that it’s time. They also point out that windows make up around 8% of the surface area of a home. Remarkably, they are responsible for nearly 50% of the heat that’s lost or gained.
When the old frame is in rough shape the method of installation is also important. Our post on full frame vs insert window replacement will tell you how to work out which one your opening requires.
What Professional Installation Adds
The DOE is very clear on this: even the most efficient windows will leave a house drafty and will cause condensation if they’re not installed correctly. That’s particularly the case in older properties. Openings are rarely square and the walls have settled over the years.
Renewal by Andersen of Milwaukee builds every window to fit its opening. Our Certified Master Installers are well equipped to deal with what older homes tend to present (uneven wall thickness, settling, hidden damage around the frame etc). Once the window is in, they insulate and seal the cavity before the trim is reinstalled. That, combined with the Fibrex® frames and the glass options on our energy efficiency page, is what keeps the lake wind out. You can see the full replacement process on our replacement process page.
Common Questions
Does putting plastic on the windows help in winter?
Yes for comfort. It cuts the drafts and the condensation (particularly on single pane glass). The energy saving is very modest.
Does window plastic go on the inside or the outside?
Most of the kits are for the inside and they attach to the interior trim. You take the film down in spring and have a look under the window for any moisture damage.
Can I replace the windows in the middle of a Milwaukee winter?
Yes, our teams remove one window at a time and will always shut off the room they’re working in so the rest of the house remains warm.
Ready to retire the plastic?
If plastic has become part of your fall routine, let’s take a look at what’s behind it. Schedule an in-home consultation with Renewal by Andersen of Milwaukee. We serve homeowners in Milwaukee, Wauwatosa, Waukesha, Brookfield, Mequon, Shorewood, Racine, Kenosha, West Bend and the surrounding counties. Our showroom is at 1741 Dolphin Dr. in Waukesha.
