Some years ago and as an experiment, I placed 3 separate nest boxes close to each other (and at the same height) around the trunk of an old Hawthorn tree.
To my surprise House Sparrows took up residence in all 3!
So, although I've no experience of using the 'terrace' type boxes, I've certainly had House Sparrows nesting in close proximity - though more 'semi-detached' than 'terraced'.
Perhaps it's a sign of the times that with our improving living standards (so we're told

) even the birds are looking to move up in the property market
Jeff