Fit window invisible grills around the way your windows open

Measure window movement, handles and sill clearance

Photograph the window open and closed. Include the sill, frame, hinges, handles and surrounding wall. Sliding, outward-opening and inward-opening windows create different clearance requirements. Existing mosquito screens, blinds and curtains also need space after fitting.

Assess the frame and wall before anchoring window cables

The frame or adjacent wall must be suitable for the proposed anchors and loads. An older frame, shallow return or cracked surface may need repair or a different arrangement. Ask how the installation affects frame warranties, waterproofing and normal window operation.

Separate low-sill protection from outside bird problems

• For a low sill accessible to a child, discuss furniture placement and supervision as well as the proposed barrier.
• For pets, explain the animal's size and behaviour so that gaps and access can be assessed.
• For pigeons on an outside bracket or ledge, describe where birds land. A cable line inside the opening may leave that outside surface accessible.

Leave room to clean the glass and service window fittings

Agree how the glass, frame and outside fittings will be cleaned or serviced. Do not obstruct required emergency access. Confirm material details, warranty coverage and inspection instructions in the quotation, and avoid placing loads on the completed cables.