美国的房子，基本上是木头房。内墙是drywall，碰一碰没有什么事，但是踢

一脚，肯定是一个洞。听说主要是安全，小孩调皮，头撞上去，没有什么事，不会有包。如果网上看到非常不满意的东东，暴跳如雷，把头往墙上撞，也没有什么后遗症。

Drywall, also known as plasterboard, wallboard or gypsum board is a panel made of gypsum plaster pressed between two thick sheets of paper. It is used to make interior walls and ceilings.

Drywall panels are manufactured in 48-inch (120 cm) and 54-inch (140 cm) wide panels in varying lengths to suit the application. Common panel thicknesses are 1/2" (12.7 mm) and 5/8" (16 mm), with panels also available in 1/4" (6 mm) and 3/8" (10 mm). Both 1/2" (12.7 mm) and 5/8" (16 mm) panels of TYPE 'X' (a gypsum board with special core additives to increase the natural fire resistance of regular gypsum board[14]) are used where a fire-resistance rating is desired. Regular 5/8" (16 mm) panels are used (with or without light gauge resilient metal channels) where additional mass is needed for the reduction of sound transmission.

Drywall provides a thermal resistance R-value (in US units) of 0.32 for 3/8" board, 0.45 for 1/2", 0.56 for 5/8", and 0.83 for 1" board. In addition to increased R-value, thicker drywall has a higher sound transmission class