Possible Clues:

• This sort of window gets frozen at the bottom
• Built like the Eiffel Tower
• Sounds like Garrett is in the French district for opening of a cross-section of bars
• With a network of crossed bars
• Went first round loft and fretted
• All in strips and frozen at last
• Criss-cross
• With slats that get frozen at the bottom
• Cattle I'd diverted with grids
• The French teetotaller on ice with slats