DIY & Building Basics A Guide To Restoring Sash Windows

Date Published:

22/10/2009

Do you have a period house with sash windows that need updating? Here’s what you need to know.

How Can I Tell If My Sash Windows Are Original?

The glass is usually the giveaway. If it shimmers and has waves or ripples it is more than likely original. The glass may also have tiny air bubbles (seeds) which add to the charm and character. As a general rule, the more wobbly the glass, the older the window - and most sash windows are between 120 to 180 years old.

Should I Replace The Glass With A More Energy Efficient Glass?

No, there is no point as the original sashes are designed to receive single glazing and modern single glazing has no greater thermal performance than the original. Besides, if you walk past a building with original sliding sash windows, you will see how the reflections of the original cylinder/crown glass sparkle. It makes the building come alive.

What If My Windows Are Rotten?

Sash windows were designed to be serviced and repaired generally every 12 to 15 years. They consist of 15 different elements, all of which can be repaired or replaced.

How Can I Get My Windows To Slide Up And Down Easily?

Your windows need to be fully serviced. They need to be dismantled, eased, adjusted, re-aligned, re-corded and re-assembled, and have a brush pile draught sealing system installed. Not only will this improve their smooth movement, it will also guard against rattling and draughts.

Both top and bottom sashes are designed to slide up and down the whole length of the box frame. This enables greater ventilation in warm weather: with both top and bottom sashes open the warm air rises out through the top sash opening and is replaced by cooler air through the bottom sash opening. Full movement also makes it easier for painting and maintenance.

Should I Replace My Old Sash Windows With Plastic Alternatives?

Your original antique sash windows contribute significantly to the character of your period property and once removed these hand crafted windows are lost forever along with the appearance of your property. Dermot Cooke, founder of Sliding Sash Solutions, which developed the Solutions Brush Pile SystemTM to remedy poorly performing windows says, ‘Not only is restoration of your windows less costly than replacement, it also has less impact on the environment by creating very little waste. PVC and plastic materials are less kind to the environment than wooden frames and casings so, again, restoring the wood and avoiding manmade materials is preferable.’

For More Information

The 4Homes' Guide To Replacing Your Window