Can you have a rubber roof gasket on a gas vent pipe from a mid efficiency furnace. I would assume no but wanted to verify.
Yes, but it needs to be a metal roof and a high temp boot (red). That is a metal roof boot and is not supposed to be installed on a shingled roof:
“If your roof is not a metal roof, but is shingled, than you should not use any of the EPDM or red Dektite types as they are only for metal roofs. Shingled roofs will not only not seal correctly with the wrong Dektite pipe boots, but the chemicals in the shingles can react with the EPDM or red Dektite, causing a reaction that ruins the Dektite and prevents a watertight seal.”
Observation: Roofing. Flashing.
Wrong vent pipe flashing.
Mid efficiency furnace flue stack temperature can reach up to 300°F or 149°C.
Collapsed rubber boot collar. Rubber boot deformed capable of trapping bulk water.
Top of rubber boot vent missing adjustable compression collar and sealant.
Metal fastener corrosion. Various.
Recommend: A licensed HVAC contractor replace the flue pipe flashing immediately.
Act upon referrals and recommendations.
Limitations: Inspected by mounting and traversing the entire roof deck. Images taken with xxxx camera.
Josh’s got it. ^^^^^^^