How long has it been since the vents were installed? If it's been more than a few years and you haven't had a problem yet, they're probably fine. (It's only been a year since mine were done.)
It's not something I thought of checking; I assumed (despite other stupid roofer tricks) that they were done properly. But I happened to be in the roof space yesterday, tracing the wiring to try to figure out why the light in my "office" flickers when the printer is running. I noticed that the roofers had dropped bits of plywood on the insulation when they'd installed the vents, looked up at the vents, and noticed the gaps in the metal mesh.
no subject
It's not something I thought of checking; I assumed (despite other stupid roofer tricks) that they were done properly. But I happened to be in the roof space yesterday, tracing the wiring to try to figure out why the light in my "office" flickers when the printer is running. I noticed that the roofers had dropped bits of plywood on the insulation when they'd installed the vents, looked up at the vents, and noticed the gaps in the metal mesh.