ventilation requirements

simple question.......how much ventilation would b required for a setup that would rely on pulling a slight vacuum to compensate for small air leaks? the volume of the space is roughly 700 cu ft

Forgot to mention will b using an inline turbine type blower and pulling thru a high flow carbon filter. in summer it will exhaust out a window and in winter will exhaust indoors .....if u pay to make heat u may as well us it eh??

I would do 8 inch dialed down.

About how many cfm would u say? thanks for the advice by the way

About 600 cfm is what an 8" makes. However, you have not given enough info to really answer the question accurately. Outside air temps? Day or night lights on? How many lights and how many plants? Active exhaust? Passive?

it really doesn't take too much to keep negative pressure on a room. An eight inch fan running @ 50% would work for sure. If smell is still leaking out turn it up a bit. hell you could probably get away with a little 4 inch fan if neg. pressure is all you wish to accomplish.

I would upsize your filter to ten inches at least tho. This will lessen the frequency at which you need to replace it as well as take some of the load off your fan.

also the less duct work and turns or elbows the better. Some sort of intake will be necessary on the room the fan is located. The intake should be smaller than the fan to put a good neg. pressure on the room . DOing this will not help to cool your room efficiently . Only keep neg. pressure on it. You will see some cooling effects . Mount your filter near the ceiling to remove the warmest air in summer.

I put negative pressure on an entire building, with a little 6 inch fan running @ 50% .

What he said.To be specific a 350 CFM fan would be plenty.

I was thinking about this..and the fact that sealed hoods leak like a sieve. You would probably do well to mount a 6" fan ducted to your hood and get rid of the glass.

So carbon filter, hood, fan, outside.

You never want to blow into your CF. you will quickly clog it with dust and debris. That is why try come with a prefilter