Kevin Nolen

Thanks for the advise.  It's greatly appreciated.  
I look forward to receiving the book.  

Thanks for the response.  I've ordered the book.

My main objective is to keep some patio plants alive through the winter.  I would also like to grow some vegatables and other plants during this time.  I also plan on starting all of my garden plants in the greenhouse, from seeds.

Winters here in west Tennessee aren't very harsh (daytime temps usually 40's - 50's, nighttime temps usually 20's - 40's.  The greenhouse stays plenty warm during the day but cools really quickly at night.  I would like to be able to divert the heat from the
greenhouse during the day.

I would like to build a simple rocket mass
heater for an existing 16’ x 20’ greenhouse.
I would rather it be outside, with the heat
piped in. I live in west Tennessee. I’m new
at this and would appreciate any advice.