"Don Phillipson" ) writes:
Town house is American realtor language
for the British terrace house or row house.
It is a single family house attached to both
neighbours (except for the unit at each end
of the row, which qualifies as semi-detached.)

I've always felt that calling the end unit in row housing 'semi-detached'
is incorrect.

We have quite a few true semi-detached homes here in Ottawa. Calling an
end unit row house 'semi-detached' is misleading. My opinion only.