Custom verge flashing: how to prepare a drawing for fabrication?

Label the gables with letters and individual sections with numbers on a simple building plan. Add the same references to photographs. “Left” and “right” are ambiguous without a viewing direction; an arrow on the sketch helps the installer and workshop identify the edge being discussed.

Show the finished flashing legs, bends and position relative to the bargeboard and covering in the section. Each dimension needs defined start and end points. A photograph with a measuring tape can support the drawing, but perspective is not a reliable way to infer missing dimensions.

Do not use the same figure for finished flashing width and flat blank width without checking what it represents. The workshop determines the developed blank for its fabrication process. The owner and roofer should primarily agree the geometry of the element that must fit the roof.

Where the edge changes height or is not straight, record separate measurement positions. One mid-length measurement does not describe the whole section. Before ordering, the installer should decide whether different flashings or correction of the support are needed. Do not assume the metal can be forced to fit.

Mark the coated face and the surfaces visible from ground level. Include the coating designation and colour from the agreed roofing order. Similar screen colours do not establish a material match; compare physical samples when visual consistency is important.

Distinguish pieces sharing the same section from those requiring a mirrored form. Agree the side-identification convention with the workshop before fabrication. Simply rotating a finished profile may put the coating or a bend on the wrong side and make the piece unsuitable.

For every reference, record quantity and agreed length. Separate the roof-edge dimension from element lengths allowing for joints. The roofer determines joint positions and eaves and ridge terminations for the selected system. Do not choose an arbitrary overlap simply to use an entire sheet.

Treat fixings as a separate item to agree. Supporting material, load requirements and joint arrangement affect fastener selection. A fabrication sketch for bending metal is not automatically a fixing design. Failing to distinguish the two can leave an important part of the order without a responsible person.

For an unusual section, ask about making one piece or sample for checking. The installer assesses the fit under agreed conditions. Link approval of the sample to the drawing number and date so a later dimensional change cannot be confused with the earlier version.

Send changes in one updated schedule and identify the revised items. A short message containing a new number but no element reference may be insufficient. Ask for confirmation that the correction arrived before fabrication began. Keep the approved schedule with the order correspondence.

At delivery, compare quantities, references and sections with the approved schedule. Inspect the coating and bends before storing the pieces. Photograph a doubtful detail and discuss it with the supplier; cutting a non-matching piece before resolving the cause makes assessment harder.

A clearly documented order makes it possible to trace each flashing to its fabrication drawing. Retain the schedule after installation for repairs or additional orders. It records the purchased shape and material but does not replace acceptance of the workmanship at the complete roof verge.