Thats a complicated answer. Kas on here can elaborate, but its more a function of capture area and use than anything else. If your hood is not wide or deep enough than much of the air from the bacon will miss the hood and end up in your room.

Also there is the question of HOW you use the hood. If you turn the hood on the moment you turn the burner on, before any cooking has occurred and allow it to run and creative positive air flow, that will mitigate much or the oder/smoke to begin with. Also leave the hood on for 15-30 minutes minimum after cooking has completed.

Thanks Joe. We went with the 36" hood insert over a 36" range. Good call on turning it on early to create some air flow.... Do these things typically vent into the attic or outside?

I hope you aren't venting greasy bacon effluent into the attic. If so, a historical review of the Swift meat plant fire will be foreboding. A succinct summary may be found at:

http://www.thecrimson.com/article/1963/4/15/general-alarm-fire-levels-meat-plant/

If your bacon pan is relatively centered under the hood aperture such that the hood entrance aperture surrounds a 10-degree half angle expanding cone rising from the bacon pan edges, and the bacon is cooked at a relatively low temperature so that the up-rising expanding effluent has a low enough velocity to not exceed the hood air speed at the aperture (no baffle aerodynamics advantage applies with a VaH), then you should have adequate capture and containment.

Note that VaH is actually claiming 300 CFM from the blower when mounted in the hood. The actual flow will be less due to the added pressure drops (also called pressure loss) from the ducting, roof cap, and MUA flow restriction when using only house leakage.

So, as an example, if the overall actual flow rate on maximum is a generous 240 CFM, and the hood aperture area is six square feet, then the average air velocity at the aperture is 40 ft/min. In the case of VaH, this may not be as uniform across the aperture as with quasi-commercial baffle hoods; I have no information on that aspect of VaH design. In any case, hot griddles can generate effluent velocities up to 180 ft/min, so I am imagining fairly tame bacon cooking will be needed (low sizzle).

kas

You're gonna smell bacon. Or fish. Or Schezuan chicken. Or cabbage. Everywhere. In the furniture and in the drapes. At the far end of the house. Not nearly enough capture area or CFM to work here. Give up smelly foods or get a better ventilation system.

Was 300 your area's per code max with no MUA? I would certainly get the max that you can. I would also try to fry it on a back burner (center back if there is one) so that you have the greatest capture area....I would leave the empty unwashed pan under the vent, vent on, until you are ready to wash it. I would wipe spatter up asap using a degreaser soap. That smell really can get everywhere.

Make the bacon in the oven. 300cfm would not contain the smells.

Good luck!

Thanks for all the comments. Yes, 300 is the max per code without make up air.... I think this is one of those things we'll compromise on in the house and upgrade/add make up air down the road if it really bugs us.

For the overall appliance package we ended up going with the Thermador suite. You just can't beat the bundled pricing that they provide. I know folks aren't enamored with the cooktop/dishwasher. I guarantee the cooktop will be better than the electric glass tops that we've had for many many years. As far as the dishwasher we came from a lower end Bosch and LOVED it. We upgraded to the Sapphire and I think it will work great for us.

I learned about baking bacon via GW. It is easy and definitely less messy.

I run my fan on boost 350(shhh as our city limit is 300 also)

300 is OK but wish I had bought a more powerful model to improve ventilation.

My Broan only has a fan on the left side of the unit which is not helpful. Many lower CFMs only have one fan on one side. I did not realize this when I bought it.

IMO....A 300 cfm liner over a Thermador sounds like a disaster about to happen. Whoever allowed you to buy this range, range top or cooktop and use a 300 cfm insert at 36" minimum above the counter top is a fool ........

^Agreed. It might have been OK with a standard 30" gas range, but not a powerful cooking surface that I'm betting is at least 36" wide. Remember, this stuff is never easier to add than when you have everything torn up for renovation. Have you actually gotten quotes for makeup air, or are you just assuming it will be unreasonably expensive?

As for Thermador, the dishwasher is good, rebadged Bosch. People's opinions on the cooktop vary. Namely some people don't like the XLO feature that cycles the burner on and off automatically for the super low simmer. Personally I wouldn't mind that at all and actually really liked the feature when I used someone else's cooktop. Other than that the cooktop is great, more powerful than many other high end cooktops and has the star burners for better heat distribution to the bottom of the pan. And the Thermador fridge reviews have overall been very positive. My biggest area of concern with that package would actually be the oven.

In upgrading the hood flow rate, we must first and foremost concern ourselves with safety. The safety issue, which drives the MUA requirements, is the presence of combustion appliances (gas furnaces, dryers, hot water heaters, for example) that might be back-drafted by a powerful kitchen hood blower. If combustion appliances are not present in the home, or have their own MUA, or are otherwise air-path isolated from the kitchen air, then a simple, bordering on poser, MUA will be sufficient if one doesn't care if the hood flow rate is restricted by MUA pressure loss. Few inspectors are going to measure house pressure under full hood power unless the MUA code requirement is specified as a maximum differential pressure.

Simple MUA means a duct to outside with some means of keeping it closed when the hood is not running. When combustion appliances are affected by the hood, then the MUA path itself has to keep the differential pressure below -0.03 inches of water column (w.c.) to avoid back-drafting, and this requires very low flow restriction or else blower-augmented MUA. In such a case, the cost of the MUA system may become significant.

In either case, in some locales conditioned MUA (at least heated) may be required. This will add some cost but if electric heating is used, the complexity is minimal.

Bottom line, a performance range should be thought of as having two extra-cost HVAC appendages -- an exhaust ventilation system and a replacement air ventilation system. In some cases, these can have the character of a 100% tax on the range.

kas

Thank you for all the feedback on that hood vent and MUA. The other option was 700 CFM and the appliance sales person quoted MUA at roughly $3k. I am going to speak with our builder in more detail later this week and figure out the plan.

Outside of smells that cannot exit, are there additional problems we may have with high end cooktop and 300-450 CFM venting?

Make up air kit cost $349.00 again your sales person is a fool.

^That sounds like the "poser" passive makeup air system kaseki was describing. Yes it's cheap and you can get away with it in many cases, but in other cases it isn't optimal and won't work. Far from the holy grail makeup air solution many appliance stores are pushing it as.

Yes if you use an underpowered hood there will be disadvantages other than lingering smells. You could have smoke that doesn't get exhausted going in your face and all over your kitchen. Hoods exhaust heat as well, so the cooking area will be hotter with those powerful burners.

Pick 2 of the 3:

1. Powerful burners

2. Effective ventilation

3. Reasonable price

And then there's the whole issue of what to do in cold climates. The common "simple" solution is to dump it into the HVAC return duct and interlock with the furnace blower but that is rarely a good idea. Most furnaces need the mixed air return temperature to be at or above a certain temperature, say 55 degrees. With the size of typical residential HVAC systems, you are not bringing 400+ CFM of freezing outside air in while staying above the required mixed air temp!

Basically, as kaseki said the best way to do makeup air involves a fan forced solution, with tempering if required provided by electric heat strips or a hot water coil.

Go ahead and try it, or do a test run with simmered cinnamon sticks. It might not be perfect, bu you aren't really going to smell bacon in the far reaches of your home for eternity.

Tempering makeup air is not a cost effective option for most people @ $3k +. So the options are....

1) Work with less cfm to the point where the removal of smoke and grease is ineffective, as it might be in this case.

2) Buy a MUA system that does the job just fine, which in turn allows the OP to purchase the correct CFM need for a thermador.

3) By tempered Make Up air system.

I would say 90% of people would select option 2..... I can only recall one poster on this site who purchased a "Tempered System" in the last 3 years since MUA made the code list in many states.

On the other hand I recall hundreds who purchased a MUA system for s few hundred $ and have not come back and reported it to be an issue in hot or cold climates. I could be wrong but thats my recollection... Sure if money was is no issue buy tempered, but if its a budget were working to buy whats needed to do the job then get the right cfm's IMO....

Jakvis - finally someone with the right perspective!

In all seriousness, I would say that 95%+ of the food we cook makes the house smell wonderful. Outside of removing smells from bacon, curry, fish, etc is there any benefit from higher CFM?

[Hand up] Me me

Reducing the rate at which the walls and ceilings have to be cleaned and repainted.

Avoiding having a house odor that doesn't go with the meal du jour.

Avoiding floor dust sticking to the floor instead of being easily vacuumed.

Providing a better environment for pet species that are particularly sensitive to odor.

Of course tempered makeup air systems aren't always needed and I didn't say that. Though, they are required by code in some places and in some climates can get awful uncomfortable with the proper MUA if it isn't tempered. Anyhow, the only reason I mentioned tempering at all was to illustrate why not to dump makeup air into your HVAC return duct. My main point was not to compare tempered vs. non-tempered MUA, but instead passive vs. active MUA.

Less tight homes without backdrafting concerns may need little to no makeup air. Yet, the code still applies to them, so a damper could be a cheap, effective way to satisfy the requirement.

In tighter homes where non-direct vent combustion appliances are a factor, Kaseki did a good job explaining why the passive damper system is worthless (even if popular and to code), and an MUA fan should be used, tempered or not. Even here you could pull it off with a passive systems, but you would need such wide openings and so many dampers that it would be impractical and more costly than a fan-forced system. It used to be that fan-forced systems were a pain because you had to custom-spec everything like Kaseki did in his own home, but now Fantech sells a neat packaged solution with a variable speed fan.

Do it right, even if other people aren't. Makeup air is a safety issue and not something to mess around with.

You'll be fine. People have fried bacon for years without venting at all. I use an electric skillet for larger amounts of bacon instead of using my range. No problems no horrid smells. No grease on the cabinets or counter. Properly cooked bacon is a slow process over low to medium heat. I only turn on my vent for heavier cooking.

All this angst on this forum about venting is downright silly. Unless you are high heat cooking for hours on end on all burners the recommendations are way over rated. And some people just love to spend other people's money. It's refreshing to hear the appliance dealer didn't try to upsell you.

Cooking smells in houses is a good thing. It's what makes a house a home.

Range hoods are for removing combustion products,smoke, heat, airborn grease, and steam from the area above the cook top. They were never designed to be whole house ventilation systems.

Windows let in fresh air. Range hoods remove cooking effluent.

"Cooking smells in houses is a good thing. It's what makes a house a home"

Agreed, while the cooking is actually happening. Not the next day. Opening the windows is great but not feasible year round in all climates.

That said, I have lived in places with no ventilation as well, and I would go back to that any day before I took an overpowered hood with inadequate makeup air.

The people who are telling you that you need the big hood for that range and to do it now, not after the fact are doing you a really great favor. I don't get the $3K pricing on the hood; there are tons of hoods for less. Does it include the MUA in that price? You really need to look into this now. In my area, Los Angeles, everyone will gladly install a hood during a reno but afterwards, there are very few and only if there is a straight path through the roof. Is the pricing coming from the contractor? If so, consider, that they may be quoting high prices to discourage you from it because they don't want to do it now...and won't be doing it later.

Who on earth thinks rancid grease smells good? Even ''good'' bacon grease will be aerosolized and float around the house without adequate ventilation. After a few months of that, you get a stale rancid smell that won't leave. Especially in your soft furnishings. People get nose blind to a lot of smells in their homes. Just visit a few multiple pet owners. Or cabbage cookers who don't vent. The houses all smell. The owners just don't smell it.

Many people buy 600+ CFM hoods but find that the low setting (100-150 CFM) is more than adequate and pretty much don't use the mid to high settings. I think you will actually find that 300 CFM will meet your majority of needs.

Now this thread has made me hungry so I'm going to make a BLT with extra bacon !

Mmmm Bacon.......

What Jakvis says is true, but I wouldn't suggest that low setting for much more than steam. One thing that is also true (but which Kaseki can explain well and I can't) is that a high powered fan works better at its lower range than a low powered fan at its higher range even though the cfm numbers might be the same.

I've had decent venting for many many years and mega venting in the new house. But until we built the new house, we always had a range, not a wall oven. With the prevalence of wall ovens, I don't read anything about venting of smells.

I'm not talking about baking bread, here, many people cook bacon in the oven, or a lot of roasts. Sometimes the wall ovens in new and large kitchens are nowhere near the vent-- where do those smells and aerosols go? I ask because I've never heard of this as a concern.

(This is coming from someone who "tested" their new smoke alarms by heating a pizza stone pretty hot. You know that faint bit of cheese oil they sometimes contain? Well, the fan above the range always grabbed it, the one just 5 feet away didn't, of course.)

I think the concept was that at equal flow rates (CFM), a higher capability flow rate fan running at low speed will cause less blade turbulence noise than a lower capability flow rate fan running at its maximum speed. The option to choose between them may not apply in all circumstances.

k

That's a good point about wall oven venting. They used to make those pull out vents above wall ovens but they no longer do. The best you could do is probably a general exhaust fan close to the oven. The other thing is, since lots of ovens nowadays require closed door broiling and have catalytic converters, it's not as much of an issue as it used to be.

That's interesting, hvtech. I didn't realize the technology had changed. Maybe that explains why it isn't a topic I've seen discussed. But now I have a baking steel that doesn't absorb anything!