Not sure if this is the right board but it seemed most appropriate... it is after all a home furnishing!
Just very, very small.

I needed a tiny couch for a project, and when I couldn't find one the right size I decided to make one. It's made of about $1 worth of basswood and some fabric I had leftover from another project.
It's about 3" long and 1" deep. It's not terribly comfy, the cushions are "stuffed" with wood. But if anyone complains, it means I'm seeing tiny people and that's a problem in and of itself...
Here's the tutorial... it gets a little confusing at the end though with the upholstry. I think I need to make another one and take pictures along the way, my illustration skills are rather lacking. I also posted it on my website,
http://www.dadahaus.com/articles/dollhousecouch.php with some pictures and diagrams.
If anyone needs clarification on any part (likely) just ask!
Materials:
1/8" basswood. One 2" by 12" sheet will be plenty
glue. I used Gem-Tac, but just because it was lying around. I suppose you'd want to use wood glue.
Fabric. Just a little scrap is all you need really. The piece I used was about 6" square. You'll want to use something nice and thin though. Avoid fabrics with large patterns, as it would be lost. Each cushion is smaller than an inch square.
Tools:
An exacto knife or small saw
scissors
an iron if your fabric is wrinkled
sandpaper
Constructing the damned thing
http://www.dadahaus.com/images/tinycouchtut/framepeices.jpghttp://www.dadahaus.com/images/tinycouchtut/interiorframe.jpgThe first thing I did was construct the seat frame, which is basically a box. The only catch is, the side peices are slighly angled at the back. The side peices you see here are *not* the armrests! They are interior supports.
I just "eyeballed" the sizes of the pieces. The front peice I used is about 5.5 cm by 1.5 cm. The top of piece (B) is 2cm, and the bottom edge of the piece is about 1.75 cm. Really the only important thing is the height. If the height is OK, everything else will work itself out. Standard dollhouse furniture works on the assumption that in a 9' room, the couch seat is about 19 inches off the ground. So you just figure out the hight of your miniature space and scale the height of your couch from there.
The back piece (C) is not perpendicular to the floor but also at a slight angle. This makes the back of the couch seem more natural when it is attached. The only part of this assembly that you'll actually see in the finished product is the front peice (A).
Secondly, attatch the backrest piece. The piece I used was a simple rectangle, about 5.5 by 3.5 cm. Just glue up the bottom part and stick it onto your seat frame. The
pictureshows the view from the right side (so the part of the backrest piece you're seeing in this picture is the edge of it).
You'll notice that a bit of the back piece hangs down, due to the fact that it's glued at an angle. You can either sand off this extra bit or decide you don't care.
I went with the latter.
Now the fun part: upholstry. Cut a long strip of fabric, slightly wider than your couch, leaving about 1/8" extra on each side. Start by gluing it at the bottom rear, and work your way around the piece. Place glue at the top of the backrest, the crease between the backrest at the couch, and at the bottom front. The green lines on the
diagram represent where glue ought to go.
Pull your fabric nice and tight as you're gluing it. After you glue it down to the bottom front, cut off the excess length of fabric.
Cut notches in the fabric at all of the corners, as indicated on the
increasingly ridiculous diagram. Do this on both the right and left side. This will allow you to easily fold the frabric over the edge of the frame. Also cut a notch in the back, opposite where the seat and backrest meet.
Take a nice sharp exacto knife and cut off the flaps of fabric on the back near the top, flush with the backrest. These flaps are shaded in black on the
diagram.
Make sure you only cut the fabric on the back side of the backrest!
Tuck the flap from the front of the backrest underneath the fabric on the back (where you just cut off the flap). Glue into place.
Glue the other flaps down. They will be covered by the armrests.
Cut two armrests, following the same angle used for the side of the seat frame, but slightly taller than the seat. Make sure to account for the cushions. Glue these peices onto the seat frame.
Cut short bits of wood for the feet, glue to the bottom of the couch.
To make cushions, take a piece of foam or wood the size of the seat. Cut into three peices. Upholster each peice the same way you would giftwrap something. Place them onto the couch and... you're done!