Hello! We're working with a designer to build a fireplace outside in our backyard. The final design will be approximately 3-4' from a corner block wall in our yard.

The design looks really cool, and the designer sketched it being open on the back side of the fireplace. This is something I hadn't considered... and I really think it would be cool. There will be a dedicated gas line to start the fires, and we're planning on burning wood.

The concern I have about a passthrough fireplace is about heat. The question for you experts and people with experience is: How much heat do you loose in an outdoor passthrough fireplace, vs a traditional fireplace?

Should I be prepared for 50% loss of heat, vs a traditional fireplace with back? Or because of the wall, and the nature of fires, is it closer to 20% heat loss?

I really like the new design... but I don't want to have it just look pretty, I want it to throw enough heat to get warm and stay cozy.

thanks in advance for any help or insight you can share. :)