Right OK I see what you are saying now. The bars are in my skylights as I did not want to cut the 8 x4 insulation.these pics will explain
always seal between frames as there the easiest way to seal
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the worst way of which ive seen you do yours never go across the bars you lose light due to the bar but its the most ackwardest way to seal the skylight up
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That's how they fell.
Also I have not sealed any Pir Foam to the roof bars anywhere. As you say I was building a suspended ceiling sealed at plastic covering level.
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