WHY IS IT THAT THE CONSTRUCTION OF BUILDINGS IN EUROPE DOESNT HAVE A SPACE BETWEEN THEIR COMMOM SIDES?

Question

THERE SHOULD BE A SPACE BETWEEN ADJACENT SIDES OF BUILDING FOR BUILDING CODE PURPOSES

Answer 1

Why don't townhouses and condos have spaces either?

Space between buildings is important for access and property lines, but there is no reason from a structural reason why you can't share a common wall.  It is a more efficent design.

Answer 2

I live in a building built in 1890 that abuts on both sides.

And I lived in several that are the same for the first 20 years of my life.

(and in the US)

It's easy, needs less support, makes efficient use of the space.

And I have seen lots more being built in the last years.

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