Favourite building material?

[HungAryan]

For anything.
Churches, houses, roads, palaces, anything.

[Zephyr]

Cast Iron:

http://upload.wikimedia.org/wikipedia/commons/5/56/Central_Park_New_York_City_New_York_4.jpg

[Geronimo]

Maple and Oak, nothing beats the smell of wood

[Waidewut]

Latvian pine trees beat anything.
I was building a sauna-house, before the winter, using it.
http://desmond.imageshack.us/Himg140/scaled.php?server=140&filename=attls0687.jpg&res=medium

[Libertas]

Wood is my least favourite. I barely take it seriously as a building material.

I prefer stone and brick.

Cast iron and steel are good.

Not fussy about too much glass though.

[Gaztelu]

Wood (specifically pine) and steel are proven to be reliable materials to construct structures.

Stone also is also a good choice in rainy environments.