To expand upon Husky's reply here's a quick run through of the method you could use to 'Array' your windows in a given direction.
1. Select given line, use Split Entities tool (from Modify toolset) and split the line in required number of parts (8), remember to tick the Green cross when happy.
2.Place construction line (different layer using vertical line in this case) in the correct coordinate position (middle of spacing) and at desired length.
3.Place two construction lines, needed for next stages.Draw window and place at correct position.
4.Select window and use Copy/Move tool to create an Array. Follow the prompts given -select reference point, end of first construction line, select target point, end of second construction line. Now the Move/Copy dialog window will open.
Choose multiple copies and current layer and attributes, hit ok.
5.Array complete, turn off layers as needed.
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