Free UK Mainland Delivery
on orders over £40
How to Fit a Roof Box Safely (Without Damaging Your Car)
A roof box is the ultimate travel upgrade — but if it’s not fitted correctly, it can rattle, leak, or worse… scratch your paintwork.
Whether it’s your first time fitting one or you’re upgrading your setup, here’s how to mount a roof box safely and securely without damaging your car.
🛠️ 1. Make Sure You Have the Right Roof Bars
Before fitting a box, double-check you’ve got:
-
Roof bars fitted to your car (not just rails)
-
Enough bar width for your chosen box
-
A roof load rating that allows for the box + contents
Roof bar types that work best:
-
T-track aluminium bars for a sleek, tool-free fit
-
Steel clamp bars — slightly cheaper, but bulkier
🔗 Find Roof Bars for Your Vehicle
🔗 Read: Can You Fit Roof Bars Without Roof Rails?
📦 2. Unbox and Inspect the Mounting Kit
Most roof boxes include:
-
U-bolts or T-track sliders
-
Washers, brackets, and hand-tightening knobs
-
Instructions — read them! (they’re box-specific)
✅ Tip: If you’ve got T-track bars, use the sliders for a faster and neater fit.
📏 3. Position the Roof Box Correctly
You’ll want your box:
-
Centred between the bars for stability
-
Not too far forward (could block windscreen or antenna)
-
Not too far back (may foul the boot when open)
Ideal positioning: even overhang front and back of the bars.
🧼 4. Protect Your Paintwork
To avoid damage:
-
Clean your car roof before fitting
-
Check bars and box for grit or debris
-
Use rubber pads or foam strips between the feet and the car if needed
✅ Pro tip: Apply a light layer of wax to the roof beforehand for extra protection.
🔒 5. Tighten Securely – But Don’t Overtighten
-
Tighten all bolts evenly and firmly
-
Don’t use tools unless the instructions say so
-
Overtightening can crack plastic bases or dent rails
✅ Shake the box after fitting. If there’s play — reposition and refit.
🔐 6. Lock Everything Down
Most modern roof boxes have built-in locks — use them!
Also:
-
Lock the box when driving (some won’t shut without it)
-
Double-check bar clamps are secure
-
Consider anti-theft bolts or locks for added peace of mind
🧪 7. Take It for a Test Drive
Do a short local test run:
-
Listen for whistling or vibration
-
Check clearance in car parks or home garage
-
Stop and recheck clamps after 10–15 minutes
🔗 Read: How to Reduce Wind Noise from Roof Bars