OK- back to it...

Couple more ventilation notes, and then on to room prep.

I heartily recommend using thru-wall flanges anywhere that you need to run ductwork thru a partition. Fer instance- You're using a window to exhaust... First, Mount a mini-blind in the window.(Camoflage from outside). Leave the window cracked open a few iches top and bottom,so that air can flow easily around the sash. Now cut a piece of luan (good) or cardboard (cheap) that fits inside the interior casing, flush against the stop. ( The stop is the piece of molding that holds the sash in the window opening, preventing it from falling into the room.) This should block the entire window. If you're dealing with a newer (vinyl) window, you won't have a stop- instead, the body of the window unit will but right up against the casing. You'll mount your blackout panel against this instead.

Put the blackout panel in place and make sure it fits well. Determine where on the panel you're going to run your exhaust- cut a hole ( holesaw), sized to match your fan's output dimension. Home Depot and the like, in the HVAC section, will have ??starter flanges?- they're used to mount branch ductwork off of sheet metal mains. They look like a little top-hat that somebody has punched through. (Again, sized to your fan's output dimension- if you're using a 6? fan, you'l be using 6? flanges and 6? duct) Mount this with a couple of short screws over the hole in your blackout panel, so you have a nice clean, light-tight place to mount your ductwork. This will essentially eliminate issues with ductwork coming loose ( and beaming a veritable bat-signal out your window), which is not uncommon when you start pressurizing flexiduct. If you wish to use this window as an intake as well, put your exhaust port high, and use multiple intake ports at the bottom. To light proof the intakes, merely attach ductwork to the starter flanges that you put over your intake holes and allow to bend down 90 degrees. I'd also advise ( strongly) putting insect screening over the intake holes from the outside- you can just glue it in place with caulking.

On a wooden window, I'll usually affix this with some wire nails ( very wee)- On a vinyl window, I use cheap acrylic non-siliconized caulking, as this can be cleaned off pretty easily if and when you need to make the room go away. Don't use the siliconized here, as it'll be tough to clean up perfectly.

If you're ducting thru walls or ceilings, you can usually use ?? duct coupler? units- tube of sheetmetal, sized to fit inside your ductwork, that are designed to join two lengths of duct. Cut your holes ( with the appropriate hole-saw) and slip the coupler in place. If your walls are too thick for the coupler unit to go all the way through, you'll need to use ??hard duct?- the sheetmetal stuff. Also home depot. Measure the length you need to have and cut to fit. Most easily cut if you open it up, lay it flat, trace your measurement several times with a utility knife, and then bend the sheet metal back and forth until it pops apart. Beware of razor sharp edges!

OK- so we know what our ventilation looks like, we have all of our flanges mounted- couple more details before we treat the walls.

Find your ceiling studs- a studfinder will cost about $15 , also at Casa de Pot, and will be good for really unlimited humor value ( Fer instance, you can walk up to your hubby/BF, wave the stud finder, (which doesn't go off), and mumble ??...hmm...guess I'm still looking..."- My daughter has been known to bring one to bars...) If you have a studfinder, you can skip the next paragraph..

You can often find studs by tapping on the surface and listening to the sound it produces- an open wall cavity will sound boomy, while tapping over the stud will produce a deader sound. This will get you within a few inches- now you need to poke thru the wall surface and look for wood. If you have plaster and lathe ceilings, make sure you are hitting frame and not lathe- if you hang a heavy light fixture by the lathe, you'll probabley be allright- but maybe 1 time in 10, the lathe will eventually pull free, dropping your light and 50-100 lbs of ceiling onto your garden. (Same thing with drywall anchors) Establish the pattern of your ceiling studs ( really joists, but whatever) and trace till they meet the walls. Mark the wall where the stud hits, extending the mark down maybe 3-4 ??s. Hang your panda/mylar/paint on the ceiling. Now, before you cover the marks on the walls, snap a line from mark to mark corresponding with the joist run. These show you where you can hang things from the ceiling, SAFELY.

So go buy a studfinder- or borrow your dad's ( He'll be so proud).

OK- you're ready to paint, or to hang your reflective film.

Mylar comes in 48 and 54 inch widths, and 1 and 2 mil thicknesses. I really recommend using the 2 mil if your going to use mylar- 1 mil tears like tissue paper. If using mylar, be aware that it's not perfectly opaque- you need to black out any windows that you haven't already.
Start in one corner on the ceiling. Unroll about 6? from the roll and tuck into the corner where the ceiling meets the wall, and put a few staples in. Now unroll across the ceiling, keeping the edge of the mylar paralell and butted against the paralell wall. Put staples in to tack it up every couple of feet. Keep things tight and neat- Neatness counts a whole lot. Roll right over any ventilation flanges you have previously mounted. Repeat until the ceiling is covered. Rooms are never perfectly square- overlap your mylar by a few inches so that you can adjust.

Once it's all up, tack it in place thoroughly. Staples will pull thru mylar very easily- anywhere that you need to staple, put a little square of duct tape up first and staple through that, to re-inforce the mylar. (Duct tape, by the way, uses an adhesive that gets soft when warm- don't rely on it as a growroom fastener. Here, it's just a buttress) Use a Sharply to translate your joist marks up onto the ceiling covering.

If you're hanging mylar alone, it's usually easier to run the wall covering in vertical strips, as gravity will help keep it straight. If you have a partner, run it horizontally ( One holds in place while the other staples.) Again, roll right over blacked out windows, vent flanges.
( Don't cover the door.)

Cut out the mylar to expose any electrical outlets, vent flanges, etc. I like to poke a hole in the center of flanges and make asterisk (*) shaped cuts out to the edge- gives ya a nice clean fit. Of course, be careful using a knife around an electrical outlet. Mylar is electrically conductive, so avoid the temptation to tuck the mylar under the cover plate, no matter how much better it looks.

Panda's similar, but 10' wide off the roll. You'll want to measure the length of your walls, and cut panda a few inches longer. Panda's folded do that you can pull one edge out- align w/ ceiling edge, letting a few inches run down onto the wall. Staple heartily. Now unfold panda across ceiling, stapling as you go. Panda's a lot tougher than mylar, you won't need as many staples. Same deal, same cautions regarding vent flanges, electrical outlets.

Paint's pretty straight forward- just don't lose your joist marks! Caulk the edges of any flanges going through a window blackout, to ensure that you won't have tell-tale glow from outside.

Might as well mylar, paint, or panda the inside of the door while you have all this stuff out. Make sure that the door will close properly! If you have a louvered door, or a door that really doesn't fit well, hang panda over the inside casing and install a self-adhesive zipper to allow you to open and close it. Wherever you got the panda will have the zippers, or you can get them for tarps at a lot of lumberyards. You're looking for a ?? tarp zipper?.

OK- so now you should have a highly reflective room. Grab a grease pencil or sharpy. Go inside and close the door. Block off your duct flanges. Turn off your worklights and hang out for at least 5 minutes to allow your eye to adjust. The ONLY light leaks that you should see should be incompletely blocked ventilation flanges. Anything else- circle it in greasepencil or sharpy, so that you will be able to find it again with the lights back on. Doors can be a drag- do the panda&zipper thing, or use v-seal weatherstripping if you have a problem. A door sweep is also a really good idea- go look at your storm doors to see what I mean.

This is very important- it's much easier to fix stuff now, while the room is empty.!

Once you have plants in there, you will not see the room in the dark- most folks discover their light leaks when they start seeing hermies. Prior Planning Prevents Piss Poor Performance!

Ok- gonna break again. In our next installment, you'll see why it's so important to know where your studs are.