As long as you don't have a grill, 600 CFMs should be more than enough. There is a rule of thumb that says 1 CFM for every hundred BTUs but that often overdoes it, unless you plan to run all your burners on maximum most of the time. Besides, in many locales if you go over 600 CFMs you need to worry about make-up air which can get very expensive - in some cold areas they require make-up air with even fewer CFMs.

OK thanks! You refer to cold areas. I live in snowy Canada, so this is good to know. We just had a lousy blizzard today...April 5! Ugh...

This is a rather hot topic, Lucybear. First I'd check my local code and state codes on make up air (MUA). When strong venting out of combusted cooking products is performed, it's important not to sequester your gas furnace and water heater exhaust by-products [one of which is odor-less carbon monoxide (CO)] through limiting their make up air system. Fireplaces, wood stoves can pose a similar problem too.

Many states and localities have adopted mandatory MUA regulations. This poses a quandary for cooks with high BTU ranges and organic effluents needing venting. Some say get the 1000 cfm vent when you re-do your kitchen so you can use it on high when needed. If you put in a 600 cfm vent system you won't have the option to go higher. There lies the heart of the issue if code does not specify.

I plan on a 36" range yet am not sure how BTU powerful it will be. I still want to put in a 1000 cfm vent system however, as that's what I have now and believe I'd like to continue to have the option of turning it to high on infrequent occasions. Our local and state codes are silent. My house is not tight. I know to crack a window if need be. I have many CO detectors up and check them regularly. I have the ventilation ducts in place already. I will vent again to the exterior of the house. But I won't use that high cfm without caution. And if I need to, I will add 400 cfms through my AC system, a relatively cheap and effective way to supply important make up air.

These are some considerations. I hope they help. You ask a great question.

Thank you SparklingWater! I have e-mailed our builder and asked them to discuss this issue with the mechanical contractor, to ensure we have appropriate venting and CFM's for this range oven. I believe our current spec is 600 CFM, so we need to be sure that is enough.

Just wanted to add one more thing. This likely isn't the case in your situation, but just in case it helps someone else...

If your hood is mounted higher than the standard/code recommends--which is 30-36" above the cooking surface--you should figure in add'l CFMs, and possibly even additional ventilator width. Wolf can tell you how many--it's a certain number of CFM (maybe 100?) for every inch over 36" above the cooking surface.

I have the Wolf DF 36" with an 1100 CFM blower, b/c mine is mounted about 42" above the cooking surface. That additional height is tricky to really compensate for, but the Best by Broan 58" ventilator with 1100 CFM in-line blower seems to be doing the trick.

Madeline's point is well made: height of vent hood may impact need for speed to capture the produced effluent.

Another consideration, if I may, is the "capture area" over your range. More depth to the vent, with a good blower, will capture that plume better than a narrower vent hood. Plumes (that burst of combustion) rise quickly, and if nothing is there to capture it in time, the lateral spread becomes more prominent.

In venting, depth of hood over one's burners matters.

Oh, great point Sparkling!

...and Lucy, ask your contractor to mount the hood as far out towards the front of the stove as possible. So, if there are 6" of lateral space (front to back) to play with, don't mount it flush up against the wall, mount it as far forward as possible for better capture.

Thank you so much for this! OK, so if recommended height is 30 to 36", we would definitely want to do the higher end, because my husband is 6 feet tall, maybe a bit taller. I don't want him to be constantly clocking himself!

What are the considerations for height, other than adequate venting? Is it just aesthetics and how tall you are?

There seems to be a trend on this forum that CFM requirements are strictly related to hood size, height and BTU of the cooking surface. While those are all important factors in the equation the bottom line is that no one can give a totally accurate response with out seeing your home. What is the diameter of your exhaust? How long is the run? How many turns in the run?
There is a significant loss of CFM for every 90 degree turn or even a bend in the exhaust.
A qualified installer should be able to help you factor your CFM requirement after they inspect your home and determine the requirements of your exhaust vent.
Once that is done you can look at the information you have acquired and make an informed decision.
We currently have 600 CFM over a smaller range than the OP is considering. I would want to start at 900 CFM for a 36" range and then consider the other factors that will affect the actual CFM before deciding if that is enough. Every home is going to be different even if ranges and hoods were equal.

Lucy, the height decision was purely aesthetic for us. I really wanted it to be very high and open-looking.

Of course, Docsknot is totally right, and clearly you're working with your contractor on figuring out exactly what's needed in your situation. I found the GW forum to be incredibly helpful, though, in educating me so that I could communicate intelligently with the contractors. No contractor cares about the details of your kitchen as much as you do!

Dear Lucybear05 & Laurat88,

We thought we could be of some assistance. Please refer to the Wolf Ventilation Guide linked below. As you can see on page 10, we recommend a minimum 900 CFM blower for 36" Gas Ranges, regardless of rangetop configuration.

On page 9 we discuss the Equivalent Duct Run for our units. Using a 10" round duct is ideal, however smaller duct sizes may be adequate depending on the specifics of your particular run.

If you have any further questions or concerns regarding this or any other issue, please contact us directly. You can contact us via phone Mon-Fri. 8:00-5:00 CST at 800-222-7820. We can also be reached via email at CustomerService@SubZero.com.

Thank you,

Customer Care Team
Sub-Zero/Wolf Appliances

Here is a link that might be useful: Wolf Ventilation Guide

Am I the only one who can't open the link to the Wolf Ventilation Guide? I tried to read this guide the other week and could not open it.

The Wolf Design Guide .pdf is downloading.

Hi Lucybear,

I have great page on ventilation. It covers the real issues when venting your range... If you go with a range hood that uses a 6-7" round duct work, you need to read this... Lot's of mistakes are made in this arena!
Check it out... DesigningRichmondHome.com
There is a section on professional/luxury range ventilation.
Hope it helps! Good Luck!

Here is a link that might be useful: How to vent the professional range - DesigningRichmondHome.com