Ball Python Enclosure Ventilation

I'm constructing my snake's enclosure of plywood and sheet metal (which will all be securely covered by either cement-coated styrofoam to look like rock or lizard liner on the bottom.)
The front of it is plexiglass, so i can see him.

Dimensions are 33"x19"x16" (LxWxD)

How much ventilation am I going to need do you guys think? Frank is approx 2.5' long.
I was planning on at least using a jigsaw to put six "slits" in the plexiglass door 25" long and about 1/8th to 1/4th of an inch wide. Is this enough? Options for more ventilation are to either put more holes in the door or to put some holes in the back as well for better airflow. I need to decide this now before I cement the styrofoam - harder to drill holes in cement!

Jim

What is the top going to look like?

Covered. This enclosure is actually being built into my turtle tank's stand, so making screen or other ventilation on top is not an option. The heat lamp is set to shine diagonally through a hole in the plywood "divider" screwed into the stand that splits franks tank area from the small compartment where the turtle's filter is. This part has a hinged cabiner door, whereas Frank's tank area has the plexiglass door I mentioned.

In theory, the screen on this side provides a good deal of ventilation, but only to another part of the tank stand, not to the outside.

EDIT: Divider has metal screen over the hole, so frank can't crawl out / burn himself on the heat lamp.

hmm, I would add something on the sides then, to get some cross ventilation in it.

Hey,

That sounds interesting, why won't you post some pix so we can see ?
Also if you are using plywood you could incorporate couple of old PC fans to get ventilation going

PS

yes we are pic obsessed.

The best way to setup ventilation is to have an inlet usually in the lower half of the enclosure and an oulet usually in the top half of the enclosure. This will create convection. As the warm air rises it will be replaced by the cooler fresh air.

I agree this is usually a way the ventilation is set up in PCs.
I will be installing the similar system in my enclosure.

Ig.