I'm sure it is already common knowledge that teams get a boost when playing at home. I decided to do some quick research into how much of an advantage the home crowd gives their team. I know there are many variables that could affect this such as injuries, starting goalies, etc - but my results seemed directionally consistent.
First, I took a look at home winning percentages for all GHL, SHL & BHL teams. For the purpose of a percentage, I considered OT/SO win a win and OT/SO loss a loss. The average home record and win percentages are below.
GHL: 11 - 2 - 2 - 8 = 56%
SHL: 12 - 2 - 1 - 7 = 63%
BHL: 12 - 1 - 1 - 9 = 56%
Second, I took a look at my own team's history to determine how my home record compared to my overall record. For example, my Win % this year is 80%. My home Win & is 83%. An advantage of 3%. Last year, my Win % was 72% and my home Win % was 83%. An advantage of 11%. When averaged out from Season 1 - 11, my average home ice advantage was 6%. This falls in line with the GHL/BHL results above where home ice seems to add a 6% advantage. SHL seems to be the outlier.
Finally, I tallied all goals scored in BHL this year (I did BHL since that's the league I'm in). On average, the home team is scoring 3.8 goals per game, while the visiting team is scoring 3.3 goals per game. The home team is scoring 53% of the goals. I did the same for GHL and the results were 2.66 Home for 2.27 Away. The home team is scoring 54% of the goals. These numbers seem a bit lower than the first two sets of results.
For now, until I have a chance to do more research and understanding that there are many variables that could sway these numbers, I will conclude that the home team gains a roughly 5% advantage.