  We use a one-dimensional (1-D) cloud-free climate model to estimate habitable
zone (HZ) boundaries for terrestrial planets of masses 0.1 M$_{E}$ and 5
M$_{E}$ around circumbinary stars of various spectral type combinations.
Specifically, we consider binary systems with host spectral types F-F, F-G,
F-K, F-M, G-G, G-K, G-M, K-K, K-M and M-M. Scaling the background N2
atmospheric pressure with the radius of the planet, we find that the inner edge
of the HZ moves inwards towards the star for 5ME compared to 0.1ME planets for
all spectral types. This is because the water-vapor column depth is smaller for
larger planets and higher temperatures are needed before water vapor completely
dominates the outgoing longwave radiation. The outer edge of the HZ changes
little due to competing effects of the albedo and greenhouse effect. While
these results are broadly consistent with the trend of single star HZ results
for different mass planets, there are significant differences between single
star and binary star systems for the inner edge of the HZ. Interesting
combinations of stellar pairs from our 1-D model results can be used to explore
for in-depth climate studies with 3-D climate models. We identify a common HZ
stellar flux domain for all circumbinary spectral types
