Velcro and a large piece of Black Cloth.

In rec.photo.darkroom Leonard Evens <len@math.northwestern.edu> wrote:

 Drapes. Old heavy drapes. Put them up when you need them take them down
afterwards.

      Nick

Len,
Why not buy a changing tent?  I got a Redwing tent from Calumet (I think it
was about $60 or $70).  It holds itself open with fiberglass poles, is made
of material that I can easily wipe down with a damp cloth for dust control
and has plenty of room for me to load/unload 4x5 film holders and load my
developing tanks.  When finished it folds to about 1" x 18"x24" (very
approximate as I haven't folded it in a couple years).

Even though I have a darkroom I just leave the lights on and do the dark
work in the changing tent.  Easy and cheap.  Another advantage is being able
to work at the kitchen table where you can sit in a chair.  It might be
easier on the back!

Sherman
http://www.dunnamphoto.com

For a "long term" solution to light tight doors, I use a thin adhesive
backed foam strip (available at any hardward store) to close gaps along the
edges.  For the bottom, I use a rubber insulating strip which drags on the
floor a bit (also from hardware store).  In your case, a rolled towel or two
alog the bottom edge of the door prbably would work OK.  Maybe a strip of
heavy cardboard leaned up against the bathroom side after closing might work
too.  Just be sure you give your eyes a few minutes to adjust to total
darkness before deciding there are no light leaks.

I got a piece of flat black painted plywood about 2 feet tall, the width of
the door and place it between tha jams on the other side of the door stop
so it's about 1 inch parallel from the door on the outside. I put a towel
along the outside bottom of the plywood to block any light going under the
plywood and air can then go down between the plywood and the door, turn 90
deg and go under the door. Just turn off any lights outside of the door and
you'll have darkness and fresh air.  

There's a product called v-seal that 3M makes. I use it on the top and sides of my door.
It's pretty light tight. I seal the bottom of the door with a towel. Since my room is
a dedicated dark room, the towel just lays there all the time. Just to be absolutely sure,
when the sun actually shines on the door (a couple of hours a day in the afternoon) I've
got a curtain on a rod over the door that I can pull across.

The easiest and possibly most agreeable for the spouse (this is a bathroom that gets used
on occasion I assume) is to just use a thick dark velvet curtain. Let the velvet touch the
ceiling, and extend about 6 inches beyond the door on either side. Let it drag the floor.
When not in use, restrain it behind a "tie back" on the hinge side.

   I keep a WELCOME mat on the floor just outside my DR/WC.  Folded
over and snuged up against the door, I'm safe.
   Adjacent area room lights are kept low.
   Door jam leaks or other small leaks are ignored. When processing
film I, in a manor of speaking, turn my back on them. It is what the
film sees not what you see.
   Paper will tolerate very low levels of light. It is a mistake to
think that paper must be processed in the depths of a coal
mine at night.                                                   Dan

I had the same problem and used an aluminum door tread with a rubber insert
across the bottom of the door. Since I didn't want to make it permanent (in
concrete) I cut the aluminum to fit from side to side and tapped it in place
with a hammer.
Ron Skaug

I've used two methods in the past. In one location, I made a light
trap/cornice frame inside which I had a curtain rod that supported a
black felt drape. It was wide enough to extend past both sides of the
door, and long enough to drag on the floor. Tucking it in a bit at the
bottom edge of the door worked OK. The light-trap/cornice attached to
the wall above the door, and left only a few easily repaired screw holes.

In my current setup, I simply painted the inside of the door frame and
the edges of the door flat black, and added aluminum-backed felt
weatherstripping along the inside surface edges of the door. This works
particularly well at the bottom edge by pressing it down a bit while
tightening the screws. There are commercially available light-tight
vents for doors, as well. This latter arrangement may be more permanent
than you want in your situation, though, Leonard.

cheers,

Ralph

For the seal around sides and top, get the foam tape from a hardware
store. For the bottom, if the door opens inwards, there is a weather
seal that cams down into place when you close the door. If the door
opens into a bedroom that has a carpet, then use a small carpet, roll
it up, and place it at the bottom of the door from inside the
bathroom.

A piece of plywood across the tub will give you working surface. Use
the top of the commode lid for the enlarger. Put a safelight in a
light fixture -- clamp-clip on type. Store the stuff in the closlet
when you are done. Set up/tear down time maybe 5 minutes. Solutions,
etc., stored in bottles in a dishpan under the sink.

Clips to hang film and a couple of wire loops to go over the shower
rail.

Been there, done that, and am doing it again in a summer condo I have
now.

You don't even need a darkroom to process film -- just a changing bag,
which you should have anyway for jammed cameras. A daylight tank, like
a Nikor does the trick. Bottles at the supermarket for solutions. I
use Rodinol one-shot for development, though HC-110 is good.