The correct orientation for deck installation is for the narrow trough to be down onto the support structure. This ensures that the widest crown is uppermost, providing maximum support for insulation. Direction of lay can be left to right or right to left, ensuring that the correct engagement of side lap is maintained.

A running check should be taken during installation to ensure that the closing dimension ‘X’ is maintained. A tolerance build-up due to discrepancies in steelwork and deck cover width manufacturing tolerance can occur.

To determine setting out dimension ‘X’ (Example based on D100 over 20000mm roof width)

Where sheets are cut down to make up a finishing section, the unsupported edge requires to be supported by a zed spacer.

Alternatively the closing width can be adjusted by overlapping the deck by the profile pitch:-

Based on the previous example, if the number of sheets is increased to 29 with a single one pitch overlap at each end, the setting out dimension will be:-

To determine setting out dimension ‘X’ (Example based on 20000mm roof width)

To produce a make up section, trays may be cut down their length, overlapped on the micro ribbed pan section, and stitched together at 450mm centers. In this manner the standard 600mm cover width can be adjusted to 429mm or 257mm, as indicated below.

For further information please do not hesitate to get in touch with our Technical Department at Tata Steel, E mail: technical.structuralproducts@tatasteel.com