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Detailed Application

A250 - Trim Application

Application Instructions

The A250 is a drip trim, fitted to the lowest edge of the roof usually where the rainwater flows into the gutter. The batten for the A250 should be doubled up to provide a stand off for the gutter to fi t behind the trim, with the outer batten 10mm lower than the inner batten to allow for the radius of the trim. Apply Trim Adhesive to the batten in 30mm beads at 300mm centres, rub the trim into place and nail to the decking. Do not nail through the front of the trim. Where the trims are over-lapped, they should be bonded together with a thin strip of Trim Adhesive on the inside of the overlapping trim. If the pitch of the roof is only minimal, rainwater is likely to hold behind the trim. Use a planning machine to take 2mm off the deck to allow the trim to lay flush with the board. The A250 is supplied in 3 metre lengths.

Trim Details

The A250 is designed to cover insulation so is ideally suited to use with warm roofs and has an extra deep fascia to allow gutter penetration.


  a, mm b, mm c, mm
A250 95 140 10

A250 typical application




F300/F600/F900 - Trim Application

Application Instructions

The F trim is a flat flashing, mainly used at the intersection of a pitched roof and flat roof often found on dormers. The F trim should not be laminated over completely as it will crack. It is nailed or stapled to the deck and bent up the roof slope. In this situation, the F trim also acts as an expansion facility and must only be fixed to the deck along the bottom edge. There are many other applications for F trim including vertical details where laminating would be time consuming, under the feet of air conditioning units to enable re-roofing without disconnecting, and use on some parapet wall details etc. The trim should be nailed to the deck around its edges and bandaged over any joins or nail penetrations.

Any unlaminated trim can be topcoated with the rest of the roof.

Trim Details

F300/600/900: Flat sheeting supplied in 300, 600 and 900mm widths in 20m rolls.


  a, mm
F300 300
F600 600
F900 900

F300/600/900 typical typical application



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