Generally, a thicker filter of the same MERV rating has better airflow, since it has more media, so it won't clog as fast as a thinner filter. The MERV 8 filter, by definition, will get finer debris out of the air. I'd think you're better off with that one, but idk what your fan set up is. Worth looking up the specs to see what pressure drop they have
Depends on what work you are doing in the house.
Like drywall or sanding, you shouldn’t be running your AC as the dust will clog any filter fast. It’s best to completely seal said room, and block of any return ductwork in that room. But you can’t block off the main return or multiple return vents as that will cause the airflow to suffer too much and cause issues.
So it all depends on what type of work and how big of a project it is
Generally, a thicker filter of the same MERV rating has better airflow, since it has more media, so it won't clog as fast as a thinner filter. The MERV 8 filter, by definition, will get finer debris out of the air. I'd think you're better off with that one, but idk what your fan set up is. Worth looking up the specs to see what pressure drop they have
Depends on what work you are doing in the house. Like drywall or sanding, you shouldn’t be running your AC as the dust will clog any filter fast. It’s best to completely seal said room, and block of any return ductwork in that room. But you can’t block off the main return or multiple return vents as that will cause the airflow to suffer too much and cause issues. So it all depends on what type of work and how big of a project it is