Here's some funny-but-true info that will keep you from being labelled a "kook".
In the wave riding world, there's sort of a standard to measuring waves that has no basis in anything other than tradition when giving foot measurements. Here's the general rule of thumb when measuring waves:
You may use all the numbers up to 6 feet, but when giving a range of wave size. Example- It was 1-2 feet. It was 3-5 feet. It was 4-6 feet.
Above 6 feet, you may only use even numbers, or multiples of 5. Example- It was 6-8 feet, it was 8-10 feet, it was 10-12 feet, it was 12-15 feet.
You can't say: It was 7-9 feet, it was 11-13 feet...and for some bizarre reason, saying it was 14 feet isn't acceptable. That number is rarely used to measure waves.
Above 20 feet, you only measure waves in increments of 5 feet.
Now, we move on to how to measure waves:
Basically, there are 4 ways that I've learned to measure waves, and that depends on where you are in the world.
East coast USA: Waves are measured using body parts until it gets overhead. Example: It's knee high, stomach high, thigh high, chest high, etc.
West coast USA: Also use body parts, though not as detailed as east coast. West coasters don't use "thigh high", or "stomach high". Face height is typically used to measure waves, the wave's rideable face from trough to crest. Therefore, with an average man being close to 6 feet tall, a head high wave is 6 feet.
Hawaii: 1/2 the face height. Not sure why this is done, but that's just how they do it. There's alot of theories as to why, but who knows. A head high wave in Hawaii is 3 feet.
Australia: These guys have the weirdest method that has been described to me by my Aussie friends as measured by "the powerful part of the wave". So, for example, a mushy head high wave to an Aussie would be about 3 feet, but a top-to-bottom barreling head high wave might be 5 feet. Neither measurement is accurate technically, but that's how they do it. Plus, they measure the swell height in meters anyway.
So, there's "Wave Measurement 101" for those of you still in the learning process. "