Black Knight Secondary Glazing
Black Knight Secondary Glazing

Heat Loss

Your existing single glazed windows are probably the ones that your house has had since it was built.

They are draughty, the heat loss is horrendous and they make the area around them uncomfortable to be in.


Changing them is expensive and disruptive and will never have as much character as your existing windows.


That's where secondary glazing comes in.


Much cheaper than replacing, no redecorating to do and actually more effective at reducing heat loss and eliminating draughts.


As we all know energy costs just keep on rising and the thermal efficiency of your property is becoming more and more important.


Installing Black Knight secondary windows will make a significant difference to your heating costs and give you back all those parts of the house which are unusable in the winter.


Our secondary window system is recognised as the most efficient on the market and our standard products can be enhanced even further with the inclusion of Pilkington K Low emissivity glass to reflect more of that precious heat back into the room.


Contact us on 0808 168 5208 or email us for further information.

Secondary windows are ideally suited to the requirements of Listed Buildings and properties in Conservation Areas. The external facade is often protected on these properties and replacement of the existing windows is either not allowed or must be on a like-for-like basis. This often means the cost is prohibitive.


As secondary glazing does not alter the external window at all and in most cases is completely invisible from outside it is the preferred solution for many Planning Departments.



How to combat heat loss

  • existing single glazed windows are a major source of heat loss through the fabric of the building
  • by installing secondary windows you can increase energy efficiency, cut your heating bills and reduce your carbon emissions
  • by using low emissivity glazing in our secondary window systems you can reduce the heat loss through your windows by more than 60%
  • saving energy helps to safeguard the environment for future generations
  • when used in conjunction with other energy efficient measures secondary windows can reduce your fuel bills by up to 15% per annum