Increasing rebate depth for double glazing.

[anobium]

I have a large, 1.8 x 1.2 metres arched hardwood window frame with proper leaded lights which are leaking and beyond economical repair.
I wish to reglaze the window frame which is in sound condition using double glazed units.
Unfortunately the rebates are not deep enough to accept double glazing and
I propose to remove the frame and increase the depth of the rebates with a router.
My question is has anybody on this forum done this and if so can you let me know how it worked out and what if any problems did you experience

 

[Norcon]

I had my windows done about 19 years ago. The guys who did it never removed any frames.
All done in situ.

 

[anobium]

I had my windows done about 19 years ago. The guys who did it never removed any frames.
All done in situ.

I did consider that, but the window has a series of radial astragal glazing bars from the inner arch and it would be difficult to say the least to router those in situ.

 

[big-all]

a point to note
you are removing perhaps 15-25% off the glazing bars strength then increasing the overall load by 100%
so unless they are good and chunky you are relying on the sealed units for supporting themselves and other units away from the main outer frame

 

[anobium]

a point to note
you are removing perhaps 15-25% off the glazing bars strength then increasing the overall load by 100%
so unless they are good and chunky you are relying on the sealed units for supporting themselves and other units away from the main outer frame

Fair point but the radial glazing bars are the same dimension as the stiles mullions and transoms. Ex 75x55
I probably misled you when I referred to astragal bars.
The attached pic will describe it better.

View media item 66115

 

[big-all]

7 panels will work fine have you tried asking the question off costs and size off the d/g units
you do realize you will have to pay building contol to pass them or have them installed by a fensa fitter

 

[squowse]

are you 100% sure they are rebates. sometimes it can be beadings both sides.
it's obviously a lot easier if that's the case.
worth stripping the paint on one of them and having a check.