Secondary Glazing Guarantees and Aftercare: What to Ask Before You Book
Dr Sarah Chen
Building Physics Consultant
Secondary glazing should last for decades, but only if it is made and fitted well and someone stands behind it when something needs adjusting. The guarantee and aftercare are often the last thing homeowners look at, yet they are one of the clearest signs of how confident an installer is in their own work.
Our 12-Year Guarantee on Parts and Labour
Every secondary glazing installation we carry out comes with a 12-year guarantee covering both parts and labour. If a frame, runner, hinge, catch, seal or pane fails because of a manufacturing or fitting fault within 12 years, we will repair or replace it and fit it at no cost to you. You receive the full terms in writing with your quote.
What a Good Guarantee Should Cover
Guarantees vary between companies, so always ask for the terms in writing. A strong guarantee normally separates the parts of the job and covers each one clearly:
- Frames and finishes: the aluminium or timber frame, powder coating, and resistance to warping or discolouring.
- Moving parts: runners, balances on vertical sliders, hinges, catches and locks. These wear first, so check how long they are covered.
- Seals and brushes: the parts that keep draughts and noise out. Ask whether replacements are included.
- Glass: laminated acoustic glass is very stable, but ask what happens if a pane cracks from a manufacturing fault rather than an impact.
- Workmanship: how the units were fitted, including fixings, sealing to the reveal and alignment.
Questions to Ask Before You Sign
- Is the guarantee provided by the installer, the manufacturer, or both?
- Is it insurance-backed, so it still applies if the company stops trading?
- Does it transfer to the next owner if you sell the property?
- What is excluded? Accidental damage and DIY alterations usually are.
- Is there a call-out charge for adjustments in the first year?
For a wider checklist, see how to compare secondary glazing companies.
Aftercare: What Normal Maintenance Looks Like
Secondary glazing needs very little looking after. Clean the glass with a non-abrasive cleaner, vacuum dust out of the tracks a few times a year, and keep runners free of grit. Brush seals compress slowly over many years and can be swapped without replacing the unit. Our lifespan and maintenance guide covers the details.
Repairs and Replacement Glass
Older units, including those fitted by companies that no longer trade, can often be repaired instead of replaced. Common repairs include:
- replacing a cracked or scratched pane with new glass, often upgrading to acoustic laminate at the same time
- replacing worn runners, cords or balances on sliding units
- new brush seals and gaskets to restore draught and noise performance
- re-fixing a frame that has moved away from the reveal
If the frames are very dated or the units were never sized well, new secondary glazing is sometimes better value than repeated repairs. A survey will tell you which.
Frequently Asked Questions
How long does secondary glazing last?
Well-made aluminium secondary glazing commonly lasts 20 to 30 years or more, with seals and moving parts replaced along the way. See how long secondary glazing lasts.
Can you replace just the glass in secondary glazing?
Usually, yes. Most sashes can be re-glazed, and it is a good chance to upgrade to thicker acoustic glass.
Do you repair secondary glazing fitted by another company?
Often, depending on the system. Send us photos or book a survey and we will tell you what is possible.
What guarantee do you offer?
All our installations come with a 12-year guarantee on parts and labour. The written terms are included with every quote.
