Secondary Glazing Subframe Details
Our Subframe system wraps the aluminium frame of the window with a wooden subframe. The wood used is either MDF (Medium Density Fibreboard), Luan (a dark hardwood) or Tulip (a pale hardwood). MDF is the cheapest option for the Subframe system and is easy to trim and takes paint very well too. MDF frames are pre-primed in white, Luan subframes come unfinished and Tulip subframes can either come primed white or unfinished.
Cover trims are supplied with the system to hide the wooden subframe and cover fitting srews. Most subframe secondary glazing comes with pre-drilled holes for quicker installation.
Types Of Secondary Available In The Subframe System:
Please compare this system with our Economy Odd Leg system to see the differences.
SF1, SF3 or SF4?
The subframe comes in three depths, either a slim SF1, the deeper SF3 or the even deeper SF4. With most of our secondary glazing units the SF1 is designed to screw directly to your existing windows (known as face fixing), whilst the SF3 subframe is designed for screwing into the wall slightly away from your existing window (known as reveal fixing). The SF3 provides a 16mm reveal. The SF3 system can also be mounted direct to your existing windows where the extra depth is useful for keeping your new secondary glazing away from he existing windows handles.
With our unique triple track horizontal sliding secondary the SF3 is used for face fixing your secondary glazing to your existing windows. The SF4 has been designed to proved the option of reveal fixing for the triple track secondary units. The SF4 provides a 15mm reveal.
The pictures below show the difference between the SF1, SF3 and SF4 subframes.
Please note: if you wish to order our SF4 subframe (for reveal fixing our tripple track) - at present you can not do so on the online estimator. Also if you wish to have your subframe pre-drilled you need to state this at the time of order.
What’s The Difference between Economy Odd Leg and Luxury Subframe?
The main difference is that the luxury subframe system has a wrap around wooden frame that enables you to be able to reveal fix or face fix your secondary glazing. The wooden subframe system has a nicer, cleaner finish than the aluminium flange of the Economy Odd Leg system, which makes it more suitable for use in domestic environments. The advantage of the Economy Odd Leg system is that it is slightly quicker to fit and comes at a slightly reduced cost when compared to the Luxury subframe system - you have around the same amount of aluminium but save on the wooden subframe. This could save you a substantial amount of time and money on an commercial job of 200+ windows.
Air Gap
When installing secondary glazing it is preferable to have an air gap between your secondary and your existing window of around 100mm glass-to-glass, where possible. This gap further improves both the acoustic and thermal performance of your secondary unit.
