We test extractor noise level for hobs with built in extractors 

Thanks for taking the time to comment, it's nice to know people are finding the videos of use! Steve Feb - Aug 2022: Hi reader. If you're feeling generous, please consider donating a few pounds to my personal challenge to climb a mountain. All donations go directly to 3 chosen charities. More about why I'm doing this here: www.roots.uk/expedition-w3w and you can jump straight to the donation page here sponsorme.charitiestrust.org/event/cbdf1e64-4af4-4905-865d-49ebaedb105b

Yes, that's perfect and that set uses rectangular ducting. An further option with that to turn the ducts (extra parts needed) so the air isn't blown directly onto your feet whilst you're cooking. For other readers: This is not the same as Miele Plug and Play (also used by Neff and Bora with different names) where the hob vents to the void in the back of the cabinet. There is no ducting but you need to work out where the air will go and allow for suitably sized vents. Also you don't want to do this onto cold exterior walls (chance of condensation).

Yes... but (there's always a but!): The goal is lower noise, so the less resistance to airflow the better. Thus, the larger and smoother the ducting, with as few turns as possible, the better. So, The 6 inch (equivalent diameter) rectangular duct is good, but if you use the 4 inch rectangular duct the extractor will run nosier and have a lower flow rate. 6 inch (diameter) round duct is good, technically should be better than rectangular (less surface are of duct to volume of air) but that becomes very hard to fit into cabinets, so the flat version is a sensible compromise. The fitting to the hob is rectangular. Never flexible soft pvc ducting (it will vibrate with the airflow creating it's own noise and reducing flow) although there is a type of round rigid but bendable/positionable aluminium duct tube that I have found useful in the past. Even with 6 inch duct, ideally guide vanes within the duct will help - eg: www.compair-flow.com/compair-flow/en/ but finding that type of ducting can be challenging. And finally the optimum duct will be as short as possible with as few turns as possible, but in reality you'll be working with what you have. Also for readers considering a Bora hob, you should know that the ducting must be specified (and supplied) by Bora as part of their warranty conditions. Your retailer should provide a ducting plan for your installer free, so speak to your Retailer ..or us, if you're in East Kent ;-) The Bora ducting isn't overly expensive in my opinion if you compare it with sourcing equivalent performance smooth/performant ducting. I hope that helps Steve

Hi Sarah, Pros of downdraft + hob: two appliances, if one goes wrong other probably still works and/or is cheaper to replace Cons of downdraft + hob: more intricate fitting (takes longer to fit, detail of worktop cut outs and position of motors is complicated) Cost? - I'd assume it's cheaper but that could be because you can get a lower spec hob/extractor than the all in one models tend to be. Pros/cons for all in one styles are the reverse of above :-) Which to go for? I don't think either is a bad option. The better option for you will depend on your furniture design, ducting options & how/where the motor will fit. Oh, and the cost of course! When comparing extractor performance look for a combination of Extraction Rate + Noise at given rates (no point buying a silent extractor when it's only silent at a running speed of 1m3/hr instead of the hundreds of m3/hr needed for it to be effective! - the video on hob noise tells you how to find the specs ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-SBfysIfETlg.html ). As for models, we regularly use Neff, Miele and Bora venting hobs. Neff is generally less expensive Miele and Bora are comparable in price when comparing as near like for like as possible and if money is no object I'd go for these over Neff every time. The biggest differentiator after cost is if they fit into the furniture we're using and how to duct them. Finally, the biggest differentiator right now: do the manufacturers have them in stock! Lead times on some models are 12-16 weeks so that may have a bigger impact on what models you can choose.

Hi Bill, I'd hope your retailer would've been able to answer this.... you have a couple of options: a) If you're working with a 60cm worktop depth, kit Z861KE1 has an "s" bend to connect to the hob so the vent points down. Then use your own ducting to turn through the wall (we like Compair Flow, and you can go through the wall as a circle or rectangle). b) If you're working with a 70cm+ worktop depth, kit Z861KR0 as a regular bend (which is why you need more worktop depth, but that also means you get more useful space inside your cupboard - deeper worktop useful if you want drawers below the hob). This kit also includes parts to recirculate into the room but you can throw those away and use your own ducting to turn through the wall (we like Compair Flow, and you can go through the wall as a circle or rectangle). This means you won't go through the wall at waist height level with the back of the hob, but exit slightly lower. There's also no need for flexible ducting as you trim the vertical section to height as you fit and can drill the hole through the wall before you've fitted cabinets. For location along the wall, remember the vent exit is not in the centre of the hob. Check the hob/instructions if you have them but if not the Neff web site has the technical drawings. As a last resort (because the image might be for the wrong model, or change over time) here's a link to the drawing. - media3.bsh-group.com/Line_Drawings/900x506/MCZ_03371842_2721475_PVQ711F15E_en-GB.webp I hope that helps you and and any other readers. If it did - I'm collecting some money for charity - ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-a7u_TKLhDKg.html and www.roots.uk/expedition-w3w and all donations go directly to the three good causes. Thanks, Steve

When hoods (vented or a wall mount version) recirculate the air they should have carbon filters that take out the smells. You'll need to replace the carbon filters periodically. Do carbon filters work, yes - at least I think so, but there isn't a way of testing that I've ever found and it's not mentioned in the EU standard either.

Hi Annie, I've not tested any but I'd suggest you use the EU product specifications file as a guide to performance (the testing is a standard across manufacturers). The video here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-SBfysIfETlg.html covers what words to search for to find that.

...and I just realised I'm replying to a video with a link to the same video, sorry! Still, EU standards file best way to compare and maybe I'll get one to play with in our next showroom update.

Short answer: Industry wisdom is that an extractor should be capable of removing or filtering all the air in the room 10 times in an hour. Long answer: number of meals a day shouldn't make a difference in calculations as we want to remove smells & humidity reasonably quickly when cooking. Likewise Indian cooking can be substituted for any cooking, be that boiling potatoes or frying fish. Air mixes constantly, so you have to change the air in the room more than once. If you remove air you need to replace it, so allow for doors into the room to be open, or windows ajar. If a room is 2.4m high x 4m long x 5m wide, it's (2.4x4x5=) 48m3 of volume. 10 times is 480m3 so ideally plan for an extractor with a max setting of at least 480m3/hr extraction rate. This formula doesn't work so well for open plan spaces as it's clear no extractor can reach 10 times the room, so rule of thumb it to prefer [the highest extraction rate] with [the least noise] at [a price point that works in your whole room plans]. Generally, you pay more for power+quietness. As for whether it should be built into hob or overhead, that's a function of design. I like to use wall mounted extractors where the hob is against a wall, and these venting/downdraught extractors in islands. I'll design in ceiling mount extractors where a) the ceiling is suitable and b) future access to change filters is acceptable [I worry over details like how will customers remove the filters for cleaning if they're too high. Of course, all those design choices have other factors specific to a room (how it looks, how much it costs, how it can be fitted). I hope that helps! Steve

@@RootsKent thank you so much for your prompt reply.

>"opting for a more powerful extractor (like the Bora you mentioned in your video) would allow to use it at a lower setting" Yes, so when looking at the data fiche you're comparing BOTH [extraction rate] + [noise level at that rate]. (and industry wisdom is to aim for a rate of 10 times the room volume, though that becomes impossible for large/open plan areas). Also, turn extractors onto their low setting on as soon as you think about cooking and leave them running on a low setting for a time after cooking. It takes time to get air moving so a low quieter setting for longer is a more pleasant room to be in. Neff, Bora & Miele (and probably other brands, but we don't sell those) all start the extractor as soon as you turn the hob zones on and all have an option to run on at a low setting, so they're encouraging that approach. >"..the windnoise is equal. Therefore, it could be primarily the noise from the air that you're hearing .." Often that's the case, and the motivation is for manufacturers to design filters that catch grease/humidity without increasing the wind noise, and design motors that are quiet running. The Fiat Panda will generate more wind noise than the Ferrari even if you're dragging both cars at 100mph with their engines turned off. That's why the EU product sheets are so useful, they contain rates + noise at different settings in a way that's comparable between models. That doesn't mean that's what you'll get as that depends on your room acoustics, size/type of ducting, etc >"Second question: I'm worried about food spilling into the extraction unit." .... is going to be my next video ;-)

An overhead extraction unit will make far less noise for the same effectiveness of extraction. Spilling stuff into the downdraft unit sounds like a disaster area for tenants. For quiet, try some of the units where the fan is mounted outside the building.

Most downdraft extractors have a 0,2 liter tray that sits in the filter part that goes in the dishwasher for cleaning. Siemens and Bora usually will have a 2 liter reservoir that is drained with a sponge, as such spills are not a disaster. For a rental property I would not do downdraft due to costs of replacement

Watch to the end! - NEVER trust a RU-vid video that compares noise level. I could be playing with sound levels to make you think the one I want you to buy is quieter. As I said at the end, you can compare noise levels by looking at the EU specification sheet that includes standardised test results. The actual noise level in your home will vary due to the ducting size you use, the furniture you're fitting into and the soft furnishings in your home. If you really get into noise level detail, Bora have an option for a remote filter that is quieter and changes the tone of the sound which some people prefer. I hope that helps, Steve.

Thanks for the feedback. Out of interest, what sort of tests would you like to have seen? This video came about because of another video I made where lots of comments were that the extractor is noisy. So this video was to illustrate that I can change the volume or edit the sound out of a video completely, making video a poor way of comparing models and the way to compare is the results from the EU standardised test results. I have thought about a video comparing different sizes, types and lengths of ducting attached to the same extractor (flow rate and sound level from different configurations), would that be interesting? Or are there other questions you have I haven't thought of? Thanks, Steve

⁠​⁠​⁠@@RootsKentI for one would expect hearing the noise at each speed in duct/recirculation modes, compared to some reference sounds (e.g a boiling pot, running water, your speech) and ideally compared to a hood, that one can buy for the difference between a hob with and without extractor built in. Right now I’m left wondering if these things are only effective when they’re at their highest speed, when they sound noticeably louder than everything else in a kitchen.