3 ms·

Only the outer walls would be 2 meters thick, right? So we're talking about adding less than 4 meters to the diameter of every building, which... I don't know,

Only the outer walls would be 2 meters thick, right? So we're talking about adding less than 4 meters to the diameter of every building, which... I don't know, that doesn't seem like a ton of extra space being consumed.

brudgers 5y ago
Wall area is O(n^2) not O(n). A 50x50 building with 8” CMU walls (0.2 meter) enclosed 2460m^2 floor area. With 2m walls only 2100m^2. A more dwelling sized building of say 25x10m is 246.5 versus 110m. Until I designed tract housing to with floor area targets, it was not obvious how much difference a few inches here and there made. But that’s literally how an initial design that works out around 1900sf is made to fit into the 1700sf gap in the product line…it’s not like you can lop off the kitchen.
- pwinnski 5y ago
  I was very confused by this at first! Clearly you know what you're talking about, so I struggled a minute to walk through the math. My super-naive approach is to say: infinitely thin walls would mean 50x50=2500m^2, but having 0.2m walls would make it really 49.6x49.6=2460.16m^2, so basically what you said. 2m walls would make it 46x46=2116m^2, so again, pretty much what you said. So I don't disagree on the math, but I guess I'm not sure about how much of an issue that is, especially when other factors are considered, such as: Generally either a building has a little space to expand outward in a given direction or it's smack against another building in which case that seems like more of an interior wall, not needing to be 2m thick. Right? Maybe that's where I'm lost. Like, you're talking about a 10m wide building, but I'm thinking that a 10m wide building probably already abuts a building on each side, so no airflow there, so no need for 2m walls. Whichever sides do not abut another building, and therefore might get airflow, would need a 2m wall, but it seems likely that could happen by expanding the footprint more easily than by shrinking the interior. I'm sure there are exceptions, but am I way off-base? I might be.
  - brudgers 5y ago
    The value of a building has a strong correlation to its net area. 300 square meters is a lot of area…more than a $100,000/year at $35/square foot. Over $1,000,000 at ten years. Over $3,000,000 over the life of a thirty year mortgage. And that’s per floor.

brudgers 5y ago

Wall area is O(n^2) not O(n). A 50x50 building with 8” CMU walls (0.2 meter) enclosed 2460m^2 floor area. With 2m walls only 2100m^2. A more dwelling sized building of say 25x10m is 246.5 versus 110m. Until I designed tract housing to with floor area targets, it was not obvious how much difference a few inches here and there made. But that’s literally how an initial design that works out around 1900sf is made to fit into the 1700sf gap in the product line…it’s not like you can lop off the kitchen.

pwinnski 5y ago
I was very confused by this at first! Clearly you know what you're talking about, so I struggled a minute to walk through the math. My super-naive approach is to say: infinitely thin walls would mean 50x50=2500m^2, but having 0.2m walls would make it really 49.6x49.6=2460.16m^2, so basically what you said. 2m walls would make it 46x46=2116m^2, so again, pretty much what you said. So I don't disagree on the math, but I guess I'm not sure about how much of an issue that is, especially when other factors are considered, such as: Generally either a building has a little space to expand outward in a given direction or it's smack against another building in which case that seems like more of an interior wall, not needing to be 2m thick. Right? Maybe that's where I'm lost. Like, you're talking about a 10m wide building, but I'm thinking that a 10m wide building probably already abuts a building on each side, so no airflow there, so no need for 2m walls. Whichever sides do not abut another building, and therefore might get airflow, would need a 2m wall, but it seems likely that could happen by expanding the footprint more easily than by shrinking the interior. I'm sure there are exceptions, but am I way off-base? I might be.
- brudgers 5y ago
  The value of a building has a strong correlation to its net area. 300 square meters is a lot of area…more than a $100,000/year at $35/square foot. Over $1,000,000 at ten years. Over $3,000,000 over the life of a thirty year mortgage. And that’s per floor.