Not necessarily. If you add density to an existing lot, your land increases in value, and since it’s likely the majority of the value of your property, your property probably goes up in value. Then, the increased supply decreases the cost of shelter.
> your property probably goes up in value. > decreases the cost of shelter. Which is it?
You subdivide and build another house on the lot with building value 300K. Total land value appreciates 50K.
Outcome
Unit 1 land 175 + building 600, total 775 (and the owner gets 175 for the land they subdivided and sold off , coming out ahead 50k in cash)
Unit 2 land 175 + building 300, total 475.
Average unit cost on the lot is now (775 and 475) = 625 (30% decrease)