Floating your rate is exactly what it sounds like. If rates improve, you get the better rate. If rates increase, you assume the market risk, and take the higher rate. Given that floating puts you at risk, we typically do not advise it.
Locking your rate establishes the worst case scenario and removes your anxiety associated with a volatile interest rate market.
Knowing your options available will help you play the game…and win!
If you lock and interest rates increase before closing, you will WIN because your rate is below the current market rates.
If rates stay the same as where you locked, you will still WIN because you did not waste a lot of your time trying to figure out the rates each day.
If rates drop before your closing, you still WIN because most lenders will allow you to lower your interest rate if the market drops. The Lenders would rather lower your rate and keep your business rather than watch you walk away.
Moral of the story is you should seriously consider locking as soon as you can.