Screw size for use on Winnie fiberglass roof

[LK23]

I purchased the 360 Siphon waste vents to replace the noisy Xtreme vents on my black and gray water waste vents. The 360 Siphon vent requires 4 screws to attach to the roof. The installation instructions say to use the appropriate size screw for your roof. Does anyone know the appropriate size (or length) for Winnie fiberglass roofs?

[LK23]

I purchased the 360 Siphon waste vents to replace the noisy Xtreme vents on my black and gray water waste vents. The 360 Siphon vent requires 4 screws to attach to the roof. The installation instructions say to use the appropriate size screw for your roof. Does anyone know the appropriate size (or length) for Winnie fiberglass roofs?

[smlranger]

Since the fiberglass skin is pretty thin and there is nothing under that skin for the screws to bite into, I'd not use anything longer than 1/2", 3/4" max.

[Kazoo Tom]

Not sure exactly what size you need, you might try a call or email to Winnebago Customer service with your VIN should get you the correct answer.

[jimandsue60]

[jimandsue60]

Looking at the 360 Siphon Vent base, I would use a #8 3/4 inch sheet metal screw preferably in stainless steel. Using Dicor sealant under and over the base of the vent.

Jim