The flat is one of, if not the, most used method of building a set in the traditional sense. In this method wooden frames about four feet by eight feet are put together to build the box set. These will then be covered in wood or fabric. There are of c ourse ways to 'design' a play so that it does not need a set as such (eg in the round).
Flats are however easy to make and use. Start off by making a frame of 2x4s (though if you are using fabric instead of wood you can use 1/4 inch to make them still lighter) this frame should be 4 feet side and 8 feet tall, a centre strut should be pla
ced at a height of 4 feet. To make the joints don't try any fancy joining techniques but take some off-cuts and screw them over the join. This will have the advantage of making the easier to adapt later. Then either apply plywood onto the other side, t
his should be large enough to take any weight needed (eg pictures) but remember the thinner it is the lighter the flat will be.
If you are using muslim or another material this should be stretched taught and stapled on the backstage side of the flat.
Holes (for stuff like windows/doors) can easily be added, I will start off explaining windows as they are easier.
Cut the required hole for the window, this will probably go through the centre beam, to correct this 'divert' it up and down so it goes around the hole. If you recycle your flats simply adding two bolts onto the centre beam across the cut will enable the window to be removed and the 'filler' placed in again. Place your window frame into the hole, at this point remember you will need a backing flat behind it to give the impression of looking out a window.
Doors are slightly harder though start the same way, cut a hole and add the door frame, the centre beam should then be attached to the door frame. The door should have either a working handle or a bolt on the back stage side so that it can be 'locked' close during set changes.
Once assembled the flats will need to be assembled on stage, there are several ways to do this, I will however explain one of the simplest if you have another way I can include then please Contact Me. This method is often called the 30/60/90 triangle method. If your flats have been built properly if will work, otherwise you will need to add some weight to the supports. From the top of the flat run a length of wood (2x4?) from each of the top corners downward at an angle of about 60 degrees, this will then make an angle of about thirty degrees with the stage where it can either be screwed into the stage or have a base added. This should keep the flat at an angle of 90 degrees to the stage.