Freestanding antenna mast height.

I've been continuously pondering how to improve reception. I have a Televes DAT BOSS MIX LR and a Stellar Labs Deep Fringe antenna pointed at separate tower clusters. It's maybe about 15lbs of antenna with the lighter one being higher. I also live in West Michigan where we sometimes get straight line wind storms.

I've consider structural antenna towers, but my city lot would make the where / how of that complicated. I recently saw this blue house pictured below where the mast was just a pole, but all the way to the ground and I was inspired.

It's about 17ft to just above and to the side of the upstirs window on my house where the brick would be sufficiently strong to anchor into. Approximately the current lower right anchor point pictured. My thought was to get a 10ft (lower section) and 20ft (upper section) of 1.5in or 2in Metallic EMT conduit. Depends on what my antennas can fit. Nominally the Televes is 2in clamp, but but 2in pipe OD is slightly larger than 2in. Anyone know how big the Stellar Labs clamp is? I read somewhere that you can go up to 10 to 15 ft without guy wires. I would be at about 13ft of free standing mast above anchor points. I'd guess I have about 6ft of 1.25in mast free standing currently.

Anyone have any resources for calculating if this is a safe approach? general vibes?

I'd either use scaffold that I have at my disposal or rent a man lift.

Antenna (in poor shape) I saw

My Antennas