my growbox design , have a few questions and want an overall opinion on it

hello ladies and gents, let me first say hello, as i am new to roll it up, my name is Des and im glad to be here!
Tomorrow im building my grow box for doing SOG and my specs are going to be 4foot across x 3foot tall x 3foot deep. going to use 3 out of the 4 foot for flowering my plants and the other 1 foot im going to use for my clone station. im using 2x2s and 1/2inch plywood for the whole box. except 1 2x4 where my doors are going to be located so you can open each separately. one of my questions is what do you guys suggest i use to cover the walls ? reflective mylar? or other media? and how about sealing my doors from light ? also for this setup im going with CFLs. im going to use 4 light fixtures, each containing 4 bulbs each in the flowering area, and 1 in the clone area also containing 4 bulbs. going to space up metal hooks across the roof to hang my lights off of chains with, but is this amount of lighting good enough for growing under the SoG[sea of green] method, going with 1 plant psf? next up is my ventilation, im either going to get a bathroom ventilator from the local homedepot and hook it up in the flowering area with duct running to my window to vent it to the back of my house, and at my window im going build a wood insert with a duct mount for the ducting. im not going to have anything to air cool the box, so with the tempature here right now being between 30 degrees F and 65 degrees F, should i add a fresh air intake to the box to drag in outdoor air ? with those 2 being said what do i cover the duct holes with INSIDE the box to make sure light doesnt penetrate to my flowering area and hermy a plant? ive got the pest side of things covered so if it was needed to add a fresh air intake id be ok, and at this moment i cant think of anymore questions i need answered, so if you guys have any other suggestions or answers for my questions they would be much appreciated. Thank you for stopping to read and for those who answer/suggest, in advance i say thank you very much as this is my first grow, anything helps,luckily i have an experiences grower helping me out here & there,but he hasnt used the sog method, which i want to.

Hi and welcome to RIU! I'll answer these in the order they arrived:

1. Yes you want to cover the walls with either a while plastic or Mylar.
2. Yes those doors need to be light-tight! Build that into your design from the start!
3. With those CFL's you want to cram as many as physically possible into the box, more wattacge = more buds.
4. A passive intake is fine for small systems, as long as you're pumping the used air our of the box it will draw in fresh air.
5. To light seal your ducting make a sleeve out of some dark+dense fabric then cable tie it around your ducting/power cables/whatever.

Good luck with your grow,

thank you for the welcome and for your suggestions, whats a good media to use, or way to go about making the doors light tight ?

alright got the framework of the growbox, well more like cabinet... just need to finish cutting 3 3foot 2x4s to mount the seperating wall to heres a couple of photos of it, dont mind my background mess lol, sunlight was shining brightly into the window its infront of so i had to move it... also i got my weather stripping, should i put it on the framework before i screw the plywood to it, or once i put the plywood on put it over all cracks/ seams ?

bump, need some1 to throw some advice my way