After a recent walk around the premises of your historic or older home, you may notice rust around your steel window frames lining the basement.

Rust develops because of a lack in care and maintenance over many, many years. This is going to be especially true if you live in a seaside area, a moist/humid climate or the soil comprises large amounts of organic salt compounds.

Today we cover how to repair rusted steel window frames in your basement to ensure the least amount of damage and to keep them looking shiny and clean.

Required Safety Equipment; Considerations

Be sure to wear some protective gloves, eye goggles and a dust mask to prevent breathing in particles that flake and fly off. Rust is iron oxide and can be the cause of some major health risks if you inhale too much. Some paints, especially on older houses, may contain lead which is a known toxin.

So, safety precautions should be a top priority. If you have any doubts about your ability to do this, be sure to call an experienced professional.

Scraping; Sanding

It will be a blessing in disguise if you only have to remove rust with sandpaper, an electric sander, or some kind of scraping tool, like a paint scraper.

Removing Paint

If the frames have layers of paint, you’re going to have to remove it before getting to the rust. You can do this with a paint stripper, paint scraper, an electric sander, or sandpaper.

Ensure the frame is free of all paint before continuing with the rusty part. Try to determine whether the rust is only on the surface or if it’s ingrained into the frame.

Surface Rust

Test a small but sizable area on the rust. If sanding seems to work, continue the removal this way. You may need several sizes of the electric sander and/or sandpaper to get into small and narrow areas.

Embedded Rust

But if you notice well-attached rust to the frame, then this means the rust has been there for a while and you’ll have to take extra measures. Continue to use a sanding or scraping mechanism for the rust removal and get as much of it off as you can.

When you think you’ve got most of the surface rust gone, then go for a piece of clean steel wool, a steel brush, or a metal file. Go over the frame with firm but circular motions to ensure you get as much rust out of the metal as possible.

Rust Removal Products

Next, get a rust removal product. It should contain phosphoric acid concentrate. Wipe this rust remover over the frame and follow the manufacturer’s instructions for the best results.

In general, you’ll want to rinse this off well with water after no more than 30 minutes. Either wait for the water to completely dry or wipe dry with a lint-free cloth.

The phosphoric acid concentrate is corrosive and can damage any plant life during the rinsing stage. This is why it’s important to sprinkle some baking soda over any flowers and grasses you don’t want to be ruined. The baking soda will act as a neutralizer.

Warping; Holes

Sometimes, the rust can be so bad it will warp the metal or leave holes. This needs fixing. It will be pointless to continue your repair if you aren’t willing to fix a warped or hole-riddled frame.

Removing Warped Frames

In some cases of severity, you may need to have the frames replaced altogether.

Contrary to what some may believe, the frame isn’t welded there forever, you can remove it from concrete. First, remove the windowpane with the utmost care.

You will need a crowbar or some other kind of leveraging device to remove the frame. A gentle but firm action will be imperative.

Pry the frame down from the top and up from the bottom so it appears like a bow tie. Tie some rope or use the crook of the crowbar and pull at the center of the “bow-tie” to remove the frame.

Patching Holes

If there are holes, get some epoxy to patch the metal. This may or may not include acquiring some sort of steel fiber and will depend on the extent of the damage. Big, gaping, and deep holes are more than likely going to need the steel fiber in conjunction with epoxy.

Painting Window Frames

The only time painting would be the sole repair of rusty window frames is when the rust is not invasive and overpowering; in that, there’s only a spec or two.

Regardless of the degree of rust attached to the frames, you are going to want to complete your repair with quality primer and paint.

Prime then Paint

To ensure sure no more rust develops on the surface of the frame, the primer must be clear and water-resistant along with rust-resistant paint.

Before applying the primer, make sure the steel has a bit of texture by using fine sandpaper or an emery board (found in most women’s manicure kits).

Apply one thorough coat of the primer and wait for it to dry. If you have severe warping or gaping holes from rust damage, a second coat might be necessary. Again, pay attention to the instructions provided by the manufacturer.

Then, apply your rust-resistant paint and wait for at least two days for it to dry and set.

Endnotes About Repairing Rusted Windows

How to fix rusted window frames isn’t difficult in theory and conception, but it will take some attention to detail and meticulousness on your part. This should be easy albeit time-consuming if you have many rusted windows or if the rust inlays into the frame.

Taking the necessary steps and precautions today means less work and headaches in the future.

As always, if you have any doubts in being able to do this, please call a professional window contractor or your local hardware store.




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