A roof rack can noticeably worsen fuel economy on a new van because it increases aerodynamic drag. In real UK driving, a basic rack left on all the time often costs a few per cent, but bulky loads (ladders, pipes, roof boxes, beacons) and motorway speeds can push the hit into the high single digits or more. The faster you drive, the more it matters.
Why it happens
At town speeds, weight and stop-start driving dominate. On A-roads and motorways, air resistance becomes a big part of what the engine is fighting. Even an “empty” rack disrupts airflow; add a ladder and you’ve effectively made the van taller and less slippery through the air.
What affects the size of the hit
Speed: Expect the biggest penalty on long motorway runs.
Rack type: Low-profile bars generally hurt less than a full-length rack or high-sided system.
Load shape: Ladders and long items are worse than a flat, tidy load. Anything that sits proud of the roofline increases drag.
Van shape: High-roof and boxier vans can be more sensitive, especially if the rack sits above the roof’s leading edge.
Practical ways to reduce the impact
If you don’t need it every day, choose a rack that’s quick to remove and take it off for longer trips. Keep loads as low and as far back as practical, strap everything tight, and consider a wind deflector if you’re carrying ladders frequently (it can help noise and may reduce drag, but results vary by van and setup).
Two common follow-ups
Does it affect electric range? Yes—drag reduces range in the same way, and you’ll notice it most at 60–70mph.
Any legal/ordering points? Check the van’s roof load limit (dynamic load), rack rating, and overall height for car parks/bridges. Overloading the roof can also affect handling and warranty if you ignore manufacturer limits.
