How do I choose a vacuum cleaner and what actually matters in the specification?

Vacuum specifications are unusually poor at describing how a vacuum performs. Wattage measures what the motor consumes, not what reaches the floor. Air watts and kilopascals are measured differently by different manufacturers and are not comparable between brands. The things that genuinely decide whether a vacuum picks dirt up — how well the floor head seals against the surface, whether the brush bar is driven, and how little the air is restricted on its way through — are rarely stated as a number at all. Which means the decision is better made from the shape of your home than from the spec sheet.

What you'll need

• An honest count of your hard floor and carpet areas
• Somewhere you have actually measured to store and charge it
• A note of who in the house has allergies or asthma (optional)

Step by step

1. Start from your floors, not from the machine.Deep pile carpet needs a motorised brush bar to agitate the pile; grit sits below the surface and suction alone will not lift it. Hard floors need a soft roller or a plain suction head, because a stiff brush bar flicks debris forward and scratches. Most UK homes have both, so the machine needs either two heads or a head with a switchable bar.
2. Choose the format by how the house is laid out.Upright: best on large areas of carpet, heavy on stairs. Cylinder: lighter to carry, better on stairs and edges, more to trip over. Cordless stick: best for quick daily pickups and hard floors, limited by battery and bin size. Robot: maintenance vacuuming between real cleans, not a replacement for one.
3. Ignore motor wattage entirely.EU and retained UK rules cap mains vacuum motors at 900W, so every corded machine sold is in a narrow band. A higher figure on an older machine meant it consumed more electricity, not that it cleaned better.
4. Read air watts and kPa sceptically and only within one brand.Air watts describe the work done on the air and are closer to meaningful than motor watts. Kilopascals describe sealed suction with no airflow at all, which is not how a vacuum is used. Neither is measured to a common standard, so use them to compare two models from the same maker and nothing else.
5. Weigh it in the shop, and weigh it at arm's length.Stated weight is often the body without the wand, battery or tools. A cordless stick that is pleasant at waist height is a different machine held up to a ceiling cobweb. If you carry it up stairs, this is the specification that decides whether you use it.
6. Check the filtration if anyone in the house has allergies.A fully sealed system with a genuine HEPA exhaust filter matters far more than the filter grade on its own, because unsealed machines leak fine dust past the filter through the joints. Look for the words sealed system, and for bagged rather than bagless if emptying a bin sets someone off.
7. Cost the consumables before you buy, not after.Bags, filters and brush bars for the model you are considering, priced for five years. It is occasionally more than the difference between two machines. Check they are still sold for the maker's older models too — that tells you what availability will look like in year six.
8. Check the cord length or the runtime honestly.Corded: how many sockets you will move between to do a floor. Cordless: the runtime quoted is on the lowest setting with a non-driven head. On carpet with the brush bar and boost engaged it is often a third of that, which is the number that decides whether you can do the house in one go.
9. Look at how it is emptied and cleaned before you commit.A bin that releases into the bin without you putting a hand in, a brush bar that comes out without a tool, and filters you can reach. A vacuum whose maintenance is awkward is a vacuum that quietly stops being maintained, and it will lose suction within a year.
10. Match the warranty and parts availability to the price.Some makers offer five or more years on the motor. Combined with parts still being sold for their decade-old models, that is a far better predictor of how long the machine lasts than any performance number on the box.

Tips

• If you buy one thing above the base model, make it the floor head. It does more for pickup than any change to the motor.
• A pet household is a filtration and brush bar question, not a suction question — hair wraps the bar, and dander is the fine fraction the filter has to hold.
• Cordless machines are used more often because they are to hand. For many households that convenience genuinely cleans the house better than a more capable machine in a cupboard.
• Ask to see the machine at full extension if there is a wand. Weight at the far end of a lever is what people notice after the first fortnight.

Common mistakes

• Comparing machines on motor wattage — It measures consumption, not cleaning. Every mains vacuum sold is under the same 900W cap, so the number tells you nothing about pickup and never did.
• Buying a stick vacuum as the only vacuum for a carpeted house — Bin capacity and runtime are sized for maintenance cleaning. Doing a full carpeted house means emptying it repeatedly and, on many models, recharging mid-way.
• Buying a stiff brush bar for hard floors — It scatters crumbs ahead of the head and can mark soft floors such as vinyl and engineered wood. Hard floors want a soft roller or plain suction.

If it doesn't work

Alternatives

• Corded cylinder with a driven head: The best value per pound for a mixed-floor house. Unlimited runtime, high capacity, and generally the cheapest consumables. The cable is the price.
• Cordless stick: Best for hard floors, small homes and frequent quick passes. Batteries are the long-term cost and the reason it eventually gets replaced.
• Robot vacuum plus a proper vacuum: The robot handles maintenance between real cleans. Sold as a replacement, it disappoints; used as an addition, it genuinely reduces the work.
• Bagged upright: Still the strongest option for large areas of fitted carpet and for allergy households, because the dust stays sealed in the bag.

Questions people ask