In the last section we talked about rooms with opposing walls that aren't parallel to each other - that is, the angles in the corners are not 'square'.

Often you'll find that a room generally does have square corners, but there are also odd angles around recesses or projections. You're likely to come across them in hallways or at bay windows, or around features like fireplace hearths and staircases.

In most instances, the easiest way to mark these angles on a floor covering plan is to simply show the diagonal line as the 'hypotenuse' in a triangle.

In other words, draw in the two imaginary square sides of the triangle and write up the lengths of all three sides.

You can see that in the case of the bay window in this drawing, the depth of the recess is actually 600 mm, even though the angled wall itself is 848 mm long.

So if you're calculating how much sheet flooring is needed with the roll running towards the window, you'll need to allow for an extra 600 mm in length across the full width of 3600 mm.

For more information on triangular shapes and angles in general, go to the following lessons from the unit: Make measurements:

• Area
  
  
• Angles