The magic of thermal heating is amazing. on one side you can use thermal mass to heat and on the other you can use the lack of thermal mass to also heat.

And you can even combine the two. For example you could have a low mass sun room, with just glass for example, that is attached to the house which has two large doors. During the day the low mass room heats up quickly. Open the doors and let the warm air into the house. But at the same time you let the sun shine through the two doors into the house where there is a high mass floor, tiles for example. The tiles don’t heat up so fast but by the end of the day they are warm. When the sun goes you close the doors because the sun room is going to get cold and you want to keep that cold out. But at the same time you are keeping the warmth from the tiles in the house.

This is the same general theory with Spanish style arched entrances. The entrance patio crates an enclosure like the low mass sun room. In the day you let the large front doors open to the main entrance room that is usually tiles.

And the flip side is that during the summer when the sun is high in the sky that very same entrance patio becomes a cool shaded space.