What size rebates for single glazing?

message from A Lurker on 16 May 2004

Morning all!

I've started on the renovation of one of the outhouses that has a lot
of rotten window frames.

I'll be making up new window frames from a load of hardwood I got
cheaply and am wondering what the rule of thumb is for the depth and
width of the rebate for puttied-in (no bead) single glazing.
Presumably related to the thickness of the glass and the dimensions of
the pane.

I've googled extensively, but apart from (of all things!) the MI5 [1]
site suggesting 35mm (presumably to hold glass shards better in case
of bomb breakage) I've come up with little conclusive advice.

Some old Edwardian sliding sashes I repaired last winter had a very
small rebate - about 5/16 and a bearing on each side of only 3/16.
The top edge though was held in a groove.

Advice / experiemce please?

Regards,

AL - put out _the_lights to reply direct

[1]"Panes with an edge dimension of 1m or more should be provided with
a frame having a glazing rebate of at least 35mm giving a bearing of
30mm" from http://www.mi5.gov.uk/output/Page169.html

mrcheerful replied to A Lurker on 16 May 2004

mine are 3/8 inch plus the thickness of the glass plus the thickness of the
putty behind the glass. This gives a nice looking width of putty on the
outside. So a ball park figure is 5/8 inch or 16 mm or thereabouts

mrcheerful

jacob replied to mrcheerful on 16 May 2004

I do old window renovation etc. Typical Victorian or Edwardian sashes
or casements have rebates about 18mm x 5mm. This is much smaller than
modern windows which are anything from 18mm x 8mm upwards.
18x5 is perfectly OK if you cut the glass accurately enough but there
is no room for sprigs except as temporary holding. But its better
without them - sprigs create problems.
For a neat job there should be a clear line of sight over the 2
arrises of the rebate, through the glass. i.e. putty face and 2 faces
of rebate make perfect triangle.
More stuff here http://www.owdman.co.uk/joinery

cheers
Jacob

Archived message: What size rebates for single glazing? (UK D-I-Y House Improvement)