C# flavor

\d+[a-z]*\s+(\b\w+\b\s+){1,4}(road|street)

use IgnoreCase On

will match on

1 CASTLE PEAK ROAD

in input

"12 XYZ Court 1 CASTLE PEAK ROAD UK"

and

56A CASTLE PEAK ROAD

in input

"12 XYZ Court 56A CASTLE PEAK ROAD UK"