Can anyone give advice based on experience please?
I plan to fit a small roof vent in a T5. The roof has shallow ribs, with the low section wide enough for the cutout for the vent. But the cowling is wider, so it needs to fit on top of the ribs. This means that I need to fill and seal between the ribs in order to provide a wide enough flat surface. I want to avoid any risk of water leaking in.
Does doing something fairly crude to full the gap between ribs with Sikaflex work well?
I'm not familiar with Sikaflex so find it difficult to guess how well it'd cope with the amount of the flex there will be in the roof without ending up with hairline cracks at the joint with the metal/paintwork.
I tried making a perspex spacer as an experiment, thinking this could then be bonded neatly in the channel between the ribs (the vent base screws to the perspex). But maybe the thinner layer of adhesive would be at least as liable to developing hairline cracks at the joins? Being bonded to 3 sides of minutely flexing steel panels seems more likely to fail than something bonded to a flat surface.
So any real world experience from fitting a vent or roof hatch which spans the ribs on the roof would be welcome. Thanks!
I plan to fit a small roof vent in a T5. The roof has shallow ribs, with the low section wide enough for the cutout for the vent. But the cowling is wider, so it needs to fit on top of the ribs. This means that I need to fill and seal between the ribs in order to provide a wide enough flat surface. I want to avoid any risk of water leaking in.
Does doing something fairly crude to full the gap between ribs with Sikaflex work well?
I'm not familiar with Sikaflex so find it difficult to guess how well it'd cope with the amount of the flex there will be in the roof without ending up with hairline cracks at the joint with the metal/paintwork.
I tried making a perspex spacer as an experiment, thinking this could then be bonded neatly in the channel between the ribs (the vent base screws to the perspex). But maybe the thinner layer of adhesive would be at least as liable to developing hairline cracks at the joins? Being bonded to 3 sides of minutely flexing steel panels seems more likely to fail than something bonded to a flat surface.
So any real world experience from fitting a vent or roof hatch which spans the ribs on the roof would be welcome. Thanks!
