If you haven't taken a good look at this Zeit article and tool on aerosol risks yet, you're missing out. Get good masks, bring some for your family. https://www.zeit.de/wissen/gesundheit/2020-11/coronavirus-aerosols-infection-risk-hotspot-interiors Personally we're doing a week of quarantine before meeting any at risk family member. Beyond that we're probably accepting the risks. The car drive there will be on the same order of magnitude of danger, realistically.
This is a totally bitchin' article. It deserves its own post. One of the things that drove me crazy building the birth center, but not so crazy that I felt like mentioning it, was that the City required us to have a "hospital grade" HVAC, plumbing and electrical system that all had to be designed by a "hospital" engineer. As you might suspect, this is not actually a thing. However, there are building codes for different specialties within licensed ambulatory medical facilities so we had to do that, and we had to hire an engineer that specialized in medical design. As a consequence we spent about $40k extra, and were delayed an extra two months, so that we could pretend to be a hospital as far as the City was concerned. This was water under the bridge until one of our midwives was freaking out about a potential accidental COVID exposure and complaining about the "cramped, stuffy rooms". At which point I felt the need to shut her the fuck up. Looked up the specs and ran the calcs - our facility was designed to the same stringency as a neonatal intensive care unit. We aren't quite an operating theater but we legit do more airchanges per hour than a fucking burn unit, especially when we turn on the exhaust fans and leave them on - that literally puts us over 11 airchanges per hour (ASHRAE standards for residential are 0.35 air changes per hour). So fuckin' hell our "NICU-grade medical HVAC system" is on the goddamn website now you damn betcha. According to this, with everyone masked up, the only way anyone is transmitting COVID during an appointment is if our patients start licking us. So that's nice to know 'cuz fuck, man, they're starting to shut down maternity wards again.
The shit little blue masks are closer to felt than woven fabric which gives them better stochastic barrier performance. They can also (aren't always, but near as I can tell are most of the time) hold an electrostatic charge which attracts small particles. We've switched from cloth to hospital masks, especially now that we can get them. My walkaround masks are triple-layer woven but I keep a couple KN-95s in the car for when I'm feeling paranoid.
I had not seen that article, thanks for the link. The social spaces of the house are spacious and have 5+ meter high ceilings, which seems favorable. The dining table normally seats 16 people comfortably so social distancing during meals shouldn't be an issue for five people.