fuel odor in and under trunk

I am getting a fuel odor when I get a change in temperature in my trunk and around the fuel tank. I don't notice one when the temperature remains constant and the garage is closed. I am wondering if it could be my fuel vent hose. I ran the hose from the tank, through the trunk floor and out my fuel filler door. I have a roll over vent valve inside the fuel door. I am wondering if it could be the hose that I used. I used clear flexible PVC hose. Does anyone know if gas will permeate through PVC? I thought it should be fine for fumes. I can't find any signs of leaks anywhere. The tank is original, but was super clean inside, and never had any leaks. I used US radiator gas tank liner just to be sure. This is a new build, so everything is new. I did notice that when the temperature gets warmer and I smell gas, the hose seems to be a little softer in places.