I've just started adding dimensions to my plan, and I've noticed that the dimensions of each wall don't match the wall lengths I entered!

For example, I have one "sticking out" wall that has a length of 126, but the dimension from corner to corner measures 128.

On the other hand the opposite wall ...

Of course! Thank you!

I had an inspiration. I think I may have a different solution, if you have a scientific calculator.

1) Measure the same distance out from the corner on both sides. Call that distance a.

2) now measure the distance between those two points. Call that distance b.

3) calculate (2a^2 - b^2) / 2a^2 ...

update: I bought something similar to this and while it works brilliantly for measuring outside angles, it fails at measuring inside angles like the corner of a room.

The problem is that you can't get it into the corner; one of the two "feet" on the protractor stops you. So, buy carefully.

That's interesting. I've just found the plans, not for the room as it is now, but for the modifications the last owners had planned.

Those plans contain neither corner angles nor dimensions.

That's brilliant, thanks! I'll see if I can buy or make a bevel protractor -- I see plenty of pictures on google.

As for the building plans, if I had some, I wouldn't need to use the program...

I'm trying to create a plan for an old room in which the corners are not at 90 degrees.

I had hoped that I could just enter the wall lengths and then drag them around until the room was right in the program - but when you drag a wall it changes the length, so that doesn't work.

Has anyone got any ...