British Standard Frame & Frame Part Designations
This list covers most possibilities. The 14" x 12" 'Extra deep' or 'Deep Standard' as opposed to 'Standard Deep' (215 mm or 216 mm) type of frame does not fit with this classification. However the top bars and bottom bars from the chart below will fit. The sidebars are 254 mm long and some manufacturers make the Hoffman wings deeper on this size of frame than on the 'S2' type of sidebar.
|Pattern||Top bar||Sidebars||Bottom bars||Notes|
|DN/1||T1||S1||B1||Not self spacing|
|DN/2||T2||S1||B1||Not self spacing|
|DN/2a||T2||S1a||B2||Equal width all round|
|DN/3||T3||S1||B1||Not self spacing, Suffers badly from wax moth attack|
|DN/4||T1||S2||B1||Attracts brace comb|
|DN/5||T2||S2||B1||Recommended for brood use|
|DN/6||T3||S2||B1||Not self spacing, Suffers badly from wax moth attack|
|SN/1||T1||S3||B1||Not self spacing, recommended for honey storage using castellated spacers|
|SN/2||T2||S3||B1||Not self spacing|
|SN/2a||T2||S3a||B2||Equal width all round, Results in less brace comb|
|SN/3||T3||S3||B1||Not self spacing, Suffers badly from wax moth attack|
|SN/4||T1||S4||B1||Recommended for honey storage|
|SN/5||T2||S4||B1||Makes supers heavier for lifting|
|SN/6||T3||S4||B1||Not self spacing, Suffers badly from wax moth attack|
|SN/7||T2||S5||B2||Tendency for heavy propolisation on edges|
|T2||432||28||18||Recommended for brood use, Wedge construction|
|S1||216||22||9||Seems cheaper, but requires spacers|
|S1a||216||28||9||Results in less brace comb|
|S2||216||*||9||* 35, 36.5 or 38 mm widths, Hoffman style|
|S3||140||22||9||Seems cheaper, but requires spacers|
|S3a||140||28||9||As above, but less brace comb|
|S4||140||*||9||* 35, 36.5 or 38 mm widths, Hoffman style|
|B1||356||8||6||Recommended for honey frames|
|B2||356||8||12.5||Recommended for brood use|
All Dimensions in mm, lower portions of Hoffman frame sides 28 mm width. (Some old production will be found to be 22 mm width.)
All sidebars centrally grooved 3 mm wide x 3 mm deep to accept foundation.
Type SN/7 is also known as 'Manley type'.
My personal preference... for brood T2, S2(35), B2... for super either SN/1 (with castellated spacers) or SN/4(35) self spacing (which will still fit 11's castellations if required). I also use SN5(38) (not because of any particular benefit, but due to availability of parts). Also some of my SN/1 frames have 28 mm wide S1a sides.
For drone production I use T2, S2(38), B2.
I used to manufacture (at APEX Enterprises) A top bar similar to T3 type, but 28 mm wide, grooved hardwood (this was designated type T2B in APEX lists) it did not suffer from waxmoth attack and is a good alternative to the T3 type giving maximum brood area. I have used this type of bar (without other frame parts) for cut comb production using supers (ekes) of only 75 mm height.
I also used to manufacture various types to special order...One that was made in large quantities was similar to the T1 top bar, but 15 mm depth with a 3 mm x 3 mm central groove instead of "wedge" construction. These were used, by many other beekeepers, for cut comb production using starter strips of foundation fixed into the groove by melted beeswax.
More information on type T2A and T2B top bars.
PLEASE NOTE ! Not all manufacturers use all of the above part designations. The designations themselves were generated by the beekeeping equipment trade and are not part of the British Standard itself.