Are window vacs any good? In my experience the answer is 'HELL YES!'

I've been using a battery-powered vacuum window cleaner and I've seen the light

Kärcher Window Vac WV 6 Premium review
(Image credit: Kärcher)

I confess to having never heard about window vacuum cleaners until my editor, the most informed man in journalism, asked me to write a review of a Kärcher window vac. My first thought was, 'why anyone would want to vacuum clean a window when the task can be easily completed using a roll of Blitz and a bottle of Windolene?' Nonetheless, I duly called in the most expensive model in the Kärcher roster – the convolutedly named Kärcher Window Vac WV 6 – because, well, if the most expensive model turns out to be a lemon, what chance for all the others?

Two days later a bright yellow box arrived containing a bunch of different parts. This immediately got my hackles up because I hate products that come with loads of different bits and pieces. This one comprises a battery-powered hand unit, a charger, two different sized squeegees, two different sized Velcro-backed microfibre mops, a long black plastic thing that turned out to be a fitting for the longer mop, a squeezy bottle with screw-in squirter, a tiny sachet of Kärcher concentrated window cleaning liquid and a tiny plastic scraper for bird droppings. Needs must, so I proceeded to put them all together and ended up with two main items, one for each hand – a cleaning solution bottle with a long mop attached and the main vacuum unit to which I’d fitted the longer squeegee thingamajig.

Abseiler cleaning windows with large tool

With a window vac, you no longer need the abseiling equipment and unwieldy tools

(Image credit: Getty)

Before I continue, I should add that, like half-witted 20th century British comedian George Formby, I actually enjoy 'cleaning windas' – you won't believe the things I see. Mostly I enjoy it because the results are gratifyingly instantaneous. One minute you’re looking at a foggy view outside and in and the next it’s like you’ve had cataracts removed. It’s a similar effect to cleaning reading glasses – suddenly everything’s brighter and sharper, as if there’s no glass there at all. Of course, once you’ve seen the results of one window, there’s no choice but to continue until every pane of glass in the house looks totally transparent. But this soon becomes exhausting so you start cutting corners (quite literally) to finish the task as quickly as possible. The end result, of course, is nowhere near perfect but, hey, it’ll do.

When doing the house I usually use half a roll of Blitz paper towelling and a bottle of window cleaner, and the system works very well except for the fact that, by window number four, my arm and shoulder starts to ache and my right hand has had so much moisture sapped out of it by the cleaner’s smorgasbord of chemicals – Hexoxyethanol, Isopropanolamine, Ammonium hydroxide, Lauryl dimethyl amine oxide and Sodium dodecylbenzene sulfonate – that it resembles the Bonneville Salt Flats. Worse still, I’ve cut my fingers a number of times on flaky paint while rigorously doing the edges. Yes, I should have worn thick rubber gloves but I didn’t.

How well does a window vac perform?

Kärcher Window Vac WV 6 Premium review

(Image credit: Kärcher)

So, back to the window vac. All set and ready to roll, I headed straight for one of the large patio door windows, sprayed on the solution from about 12 inches away for better coverage and, using the integrated mop, proceeded to spread the solution around until the view outside onto the garden looked like a psychedelic Picasso painting of swirly greens and browns. So far so good and, what’s more, my hand wasn’t aching and it wasn’t covered in cleaning solution. That’s already a tick in my book – a mop and squirty bottle in one. I’ll take that.

Swapping units, I positioned the 28cm squeegee suction thing – which is apparently made from silicone for extra supple slipperiness – right at the top of the glass in one corner, switched the motor on and drew it all the way down the window in one fluid movement. Blow me down! It quite literally sucked up every last drop of liquid leaving a completely streak-free finish that made the world outside go pop. I only needed a second pass on the window to complete the task before I moved on to the next pane.

Do window vacs really save time?

Kärcher Window Vac WV 6 Premium review

(Image credit: Kärcher)

The whole process for a single inside window – from squirting and mopping to the vacuum procedure – took exactly 40 seconds. So I tried the Blitz and Windolene method and timed that, too – one minute and 20 seconds plus two wet and dirty sheets of Blitz and another for the drying.

In true pedant style, I’ve worked out that the 15 interior windows in my open-plan lounge-cum-summer room would have taken about 10 minutes to clean using the Kärcher vac and 20 minutes using my paper towel system. Multiply that figure if doing the whole house inside and out – about another 20 windows – and you can see how much time could be saved using a system like this. Enough time to watch at least two episodes of Curb Your Enthusiasm, which, incidentally, I’m trying to curb while writing this article.

Incidentally, the Kärcher WV 6 also comes with a narrower 17cm squeegee which I used for the smaller ‘vent lights’ – I had to look that term up – and the side windows on my titchy Citroen C1.

Are window vacs cost effective?

Why I'm a convert to window vacs

I now only employ five window cleaners for the upper floors

(Image credit: Aleksandar Pasaric | Pexels)

The Kärcher WV 6 costs about £100 but there are plenty of other models in its roster that are much cheaper – as low as £40 for the Kärcher WV 1 which comes with just the vacuum unit, a single 25cm vacuum nozzle and no squeezy bottle or mop.

Mind, Kärcher isn’t the only window vac manufacturer out there – you can see a few more brands in our guide to the Best Window Vacs – but since Kärcher invented the window vac and its range has been so favourably reviewed by other users, that’s the brand I thought I’d concentrate on.

In terms of value for money, I’ve worked out that I can save about £15 a month by getting our regular window cleaner to only clean the outside windows on the the top floor, which I can’t reach. I’ll happily do the rest. Add the admittedly small reduced cost of half a roll of Regina Blitz and, in the long term, a window vac will pay for itself. Of course I will still need to buy cleaning solution but I’d need that anyway.

Aside from its efficiency and speed, for me the most impressive thing about window vacs, this model especially, is how effortless they are to use. The microfibre mop system is much quicker than a ball of paper towel and it doesn't make my arm ache. My skin is also happier for it and I haven’t cut myself once on a window frame splinter or piece of flaky paint.

What else does a window vac clean?

Kärcher Window Vac WV 6 Premium review

Window vacs don't just clean windas 

(Image credit: Kärcher)

Having sorted the windows, I started looking around for other glass-like surfaces to clean and there are quite a few around the average home. The Bosch induction hob was an obvious first since the top is made of glass. For this I used the smaller 17cm squeegee and the result was astonishing. I then tried it on a polished granite worktop using just water and no cleaning solution in case it left a catastrophic stain. Bingo again! How about the fridge and all those finger smudges? Tick. The mirrors? Tick. Glass picture frames? Yes, yes, YES. 

Final thoughts

I will say this only once: window vacs rock. They save time, require less effort to use, and they genuinely clean all smooth and shiny surfaces impeccably well with no streaks and smudges. I thought they were just another ridiculous gimmick, a solution for a domestic task that didn’t require solving. But I was wrong, so wrong.

Now you know that window vacs are cool, read my full review of the Kärcher Window Vac WV 6 Premium

Derek Adams
Derek Adams

Derek (aka Delbert, Delvis, Delphinium, etc) specialises in home and outdoor wares, from coffee machines, white appliances and vacs to drones, garden gear and BBQs. He has been writing for more years than anyone can remember, starting at the legendary Time Out magazine – the original, London version. He now writes for T3, and a number of its more low-rent rivals.