Leaking stained glass window: How do you stop a leaded window from leaking?

Leaded glass windows are a striking feature for the home and can last for years and years if correctly maintained. But things do go wrong. So if you notice a leaking leaded glass window, read on and learn the best way to get it repaired.

How to stop a leaded window leaking

If you spot a leak, sealing leaded glass windows will help create a strong and waterproof finish.

It’s important to repair a leak as soon as possible to prevent mould, mildew, and rot, to help maintain the window’s structural integrity, and to prevent it from bowing.

While the different methods of sealing leaking leaded windows can be tackled by a confident DIYer, it’s a fiddly, time-consuming job. The sealing must be applied to both sides of the glass and each glass and lead joint.

That’s why for a top notch finish, hiring a glass restoration expert will make sure your leaded glass windows remain leak-free for many, many years.

Causes of leaded window leaking

A leaking leaded window can be caused by a number of issues, including:

• Dried-out or flaking putty between the glass and the lead
• Broken or missing lead
• Poor installation
• Worn-out glass seal

In older windows, smog or acid rain may have disintegrated the centre of the lead, so it just falls apart.

Look out for droplets forming on the lead came (the lead bars joining the pieces of glass together), which might drip down the window, or stand as a pool of water on the sill.

Contact a glass restoration expert in your area who can diagnose and fix the problem quickly and efficiently.

How to repair leaded window

With the right materials, it’s possible to seal leaded glass windows and keep them in tip-top condition.

However, it’s a good idea to get in touch with a glass restoration expert in your area before you go ahead. They can inspect your leaded glass windows and offer the best solution for sealing up any leaks.

Methods to seal a leaking leaded window include:

Leaded light cement

Cement is brushed between the lead and glass on both sides of the panel to waterproof it and prevent the glass from moving.

Glazing putty

Glazing putty consists of linseed oil and whiting, which hardens over time to form a tough seal. Use around the edges of the glass and push against the frame.

Wax

Applying wax to leaded glass windows will help seal the cames or lead lines. Waxing the window seals can also help prevent corrosion. Use a good car wax that contains carnauba wax.

This method isn’t as durable as the glazing putty or cement mentioned above.

Weatherstripping

Another option is to use caulk and self-adhesive weatherstrips to seal the joints. While less messy than the options above, each piece needs to be cut down to the exact size of the came. This is fine for filling in the odd gap, but resealing an entire window could take some time!

Are you unsure if you have the time or DIY skills for the job? Then leave it to the professionals!

Cost to seal leaded glass

You might be tempted to save some money, but sealing is a vital step you shouldn’t skip. If your leaded glass is left exposed to the elements, you could be looking at a total re-leading job.

A glass restoration specialist charges around £400 to seal an average leaded glass window.