Why Are My Windows Leaking?

Drafty home?  Rain water not staying outside as it should?  The culprit is most likely your windows, but why?  The answer is a simple one – any opening of a home is inherently vulnerable to leaking outside elements, even new installations of windows or doors.

windows leaking

Any aspect of your home that opens up directly to the outdoors has a potential to leak, which is why things like windows and doors should be checked periodically to ensure they’re operational.  If you’re passing by your windows, old or new, and feel a draft or see water leaking, don’t panic. The solution could be as simple as a new application of sealant.

Before you begin any project to fix your leaking windows, determine where the leak is originating from.  If the leak is coming from the window frame, or in the area between the sash and jamb, the problem may be with the window itself.

Other common causes for a leaking window can be that it wasn’t installed properly and is misaligned, clogged channels designed for drainage that end up forcing the water to leak into your home or the caulking is old and not making a proper seal.

Deteriorating Window Sealant on the Exterior

Seeping windows can be caused by the failure and deterioration of the exterior window sealant.  This problem is something homeowners likely won’t notice until they see dripping and leaking from a downpour on the inside of their homes.

How to Fix It

Properly caulking and sealing the outer rims of your windows can improve energy efficiency and help keep out the elements.  This is an easy project, and depending on how many windows your home has and requires new caulking, can take a day or even less.  The best part is that you don’t have to be an expert carpenter to use the tools needed for this job.

You will need:

  • Caulk: There are many different kinds of caulk you can use like acrylic, latex, silicone, or polyurethane.  Read the labels to decipher which caulk is best for your home and the environment it’s exposed to.
  • Caulking gun
  • Utility or putty knife
  • Good weather

Start with a clear and pleasant day

For the best results, caulking should be done on a day that’s at least 45°.  If you can, choose a day that’s not terribly humid so your new application of caulk can adhere and cure faster.

Remove the old caulk

Use your putty knife to cut and score away the old caulk.  You’ll want a clean surface for the new layer of caulking.

Apply new caulking

Equip your caulking gun with the new canister of putty and apply it to all four sides of the exterior window frame.  Smooth it out and wait a day or so for the caulk to cure completely.

Blocked Drainage System

windows are leaking

Windows often have a drainage system on the outside of the frame, also called weep holes.  If these are blocked, you could find yourself standing in some water on the inside of your house.

These weep holes can become blocked for a number of different reasons, the buildup of debris from trees dropping their twigs and leaves or even the dirt that gets washed through the system and clogs the outlets.

How to Fix It

An easily solvable problem, weep holes can be cleaned out in relatively no time at all. Just do this household task once a year to save yourself the costly repairs of a leaky window.

You will need:

  • A small, soft bristled brush or similarly small object (i.e. toothpick or screwdriver)

Clear the Obstruction

Use your small brush to clean the opening and inside of the window’s weep holes.  Clear away any debris in order for the drainage system to be fully function.

Inefficient Glass Seal

Although broken glass is a more obvious problem of leaking windows, the glass doesn’t have to be broken for air and water to leak through.  The sealant around each pane can get old and fails to seal the window glass in place as time passes.

Repairing this sealant, or window glazing, is needed for windows that have been weathered and appear to leak air or water.

How to Fix It

Fortunately, fixing the glazing compound is a relatively simple task that can take anywhere from 15 minutes to a little over an hour, depending on your experience, how cooperative the putty is and the size of the job at hand.

If you find that your windows are leaking due to the obvious missing or broken pieces of glass, now is your chance to fix this issue.

You will need:

  • A heat gun (optional, but recommended)
  • Utility knife
  • Gloves and eye protection
  • Glazing points
  • Caulk (latex) and glazing putty
  • Glass (if needed)

Remove the Window

The first step is to remove the window that’s the confirmed culprit behind your drafty home.  You can glaze the window while it’s still in place, but working with putty and trying to remove the old compound is going to be much easier when the window is taken out and placed completely flat.

Remove the Old Putty

Whatever putty was applied on your window is no longer doing its job, and now it’s time to remove it.  The putty at this point is likely dried and crusty, and so a heat gun will help make it more malleable and easier to dig out with your putty knife.

Remember to use the heat gun in a back and forth motion, concentrating the heat in one area can result in the glass cracking.

Apply the New Putty

For this step, you’ll need to decide on which type of glazing compound you want to use.  An oil-based putty will give you impressively smooth results, but will still be soft for a few days.  A latex glazing compound will dry faster and has a longer lifetime.

Apply a heavy layer of the compound around the frame and in the sides of the panes.  Next, use your utility knife to smooth out the compound as best as possible.

Finally, after the putty has dried, use your knife to cut and scrape away any excess compound.  If you’re painting afterwards, be sure to wait at least a week so the putty can cure.

Fix Your Leaking Windows

Before you panic about your leaking windows and wonder if it’s serious structural damage, check for the obvious fixes first.  Sometimes, a leaking window could just mean it simply requires a new beading of caulk or the drainage system to be cleaned out.  Seeping windows may need to be readjusted to make sure they’re aligned properly to do their job.

The easiest method in treating your leaking windows begins with prevention.  Do a window check once or twice a year to see if the caulking is holding up, the windows open and close in the correct fashion, and they drain properly.

This won’t only save you money on possible water damage and energy bills, but also prevent you from repairing your windows all at one time.  And if after you’ve checked all the obvious causes of a leaking window and still have further problems, it could mean time for you to seek a new replacement.

In such a case, Chicago homeowners trust Feldco for all their replacement window needs. Our energy efficient, durable and beautiful vinyl windows are designed for Chicago weather. Get a free quote now and join the over 350,000 homeowner who’ve counted on Feldco for their replacement window projects.

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