Common mistakes when installing blinds

Introduction

Installing blinds looks straightforward but often results in common mistakes: incorrect measurements, wrong mounting type, poor alignment, and safety oversights. This guide explains typical installation errors, how to avoid them, and what to do if installation has already been done incorrectly.

Why it matters

Installation errors cause slats to hang unevenly, mechanisms to wear out quickly, window frames to be damaged, and present safety hazards for children. Proper installation extends the life and preserves the appearance of the blinds.

Key mistakes and how to avoid them

1. Incorrect measuring

• Mistake: measuring only once or estimating "by eye".
• Problem: blinds may not fit the window or leave gaps.
• Fix: measure width and height in three places (top, middle, bottom) and use the smallest measurement for inside mount. For outside mount, account for the overlap.

2. Wrong mounting type

• Mistake: using inside-mount blinds where outside-mount is needed, or vice versa.
• Problem: blinds may interfere with the sash or not cover the opening properly.
• Fix: determine inside vs outside mounting before purchase; check frame depth and hardware clearance.

3. Inappropriate anchors and fasteners

• Mistake: using generic plastic anchors on thin frames or plasterboard.
• Problem: poor fixation, risk of falling.
• Fix: choose anchors based on wall/frame material: metal anchors for concrete, frame anchors for PVC, wood screws for timber surrounds.

4. Skipping level and accurate marking

• Mistake: mounting without a level.
• Problem: blinds hang crooked and slats stack unevenly.
• Fix: use a spirit level and template when marking drilling points.

5. Drilling in the wrong places

• Mistake: drilling near seals, hinges, or hidden wiring.
• Problem: broken seals cause drafts; drilling into wiring is dangerous.
• Fix: verify the frame construction, avoid hinges and seals, and consult a professional if unsure.

6. Improper mechanism adjustment

• Mistake: not adjusting the tension in roller or chain systems.
• Problem: blinds roll up too fast or sag.
• Fix: test and adjust the mechanism per manufacturer instructions before final fastening.

7. Ignoring child safety

• Mistake: leaving long cords or chains accessible to children.
• Problem: strangulation risk.
• Fix: use cord cleats, tension devices, or cordless systems.

8. Wrong fabric or size selection

• Mistake: choosing a blind exactly the window width without overlap.
• Problem: light leakage at edges.
• Fix: add 3–5 cm each side for outside mounts to ensure proper coverage.

Tips by blind type

Roller blinds

• Check roll direction and headbox placement.
• Ensure guides and tension are correct for smooth operation.

Venetian (horizontal)

• Precisely align brackets and centre the headrail.
• Check cord paths and ladder alignment.

Vertical blinds

• Ensure a straight pelmet and equal spacing between vanes.

Roman blinds

• Test folding and cord routing before final installation because access is limited afterwards.

Tools and quick pre-fix checklist

• Drill and suitable drill bits
• Screwdrivers, tape measure, pencil
• Spirit level
• Anchors and screws matched to the material
• Cord safety devices

Pre-fix checklist:

• Measurements checked in three places
• Level and symmetry marked
• Mechanism tested
• Fasteners appropriate for the substrate
• Child safety measures in place

Maintenance and post-installation

• Inspect and test blinds daily for the first week.
• Clean regularly with a soft cloth; check fasteners every 6–12 months.
• If you notice bending, noise, or malfunction, contact a technician.

FAQ

Should I hire a professional?

If you are unsure about measurements, drilling into PVC frames, or possible hidden wiring, it's safer to hire a pro. DIY mistakes can be expensive to fix.

What anchors are best for PVC frames?

Use frame-specific anchors or fix into the opening reveal. Avoid screwing directly into thin plastic without reinforcement.

How to secure cords for child safety?

Install cord cleats, use tension devices, or choose cordless designs.

My blinds sag—how to fix it?

Check tension and mounting brackets. Tighten or replace the mechanism if worn.

Conclusion

Careful measuring, choosing the right fixings, using a level, and ensuring child safety will prevent most installation mistakes. When in doubt, consult or hire a professional for reliable and safe results.