Iím trying to put a vent fan and a roof hatch/skylight in my bus. So I will have to cut 2 holes in the roof (mine is a metal shuttle bus and did not previously have holes in the roof).
Iím doing this build in the PNW and it rains a lot here. Especially this time of year. So I need to make sure my adhesive itís is able to set at cool temperatures and wonít be effected by moisture.
I already tried silicone while patching the holes in my floor and found out the hard way that it didnít work. Iíve heard a lot about polyurethane sealant but I want to know if it will set.
Iím definitely going to put butyl tape on all the edges but I want an extra layer or protection if possible.
I am up in the PNW area and just place a tarp elevated above my work area to keep the rain off . I dry the area out , install the item using butyl caulk and then let dry with the tarpover it for 24 hours. No issues so far. The prep work is most important.