Secondary glazing is considerably less expensive than double-glazing to install. It is also more effective at reducing noise pollution than sealed units due to the increased gap between panes. It makes your property more energy-efficient and helps cut your heating bills. Fitting is quicker and less intrusive. You still retain the external look of your existing glazing.
If your property is a listed building, or in a conservation area, you may not even be allowed to install double-glazing. You need to contact your local planning authority to check as you will require planning permission. This is not the case with secondary glazing.
Secondary glazing is also a very flexible solution offering temporary or permanent fitting to existing wooden framed or sash windows, single or double doors, and even added to existing uPVC or aluminium double-glazed units for extra protection.