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UNIT 4: KEEPING THE WATER OUT (ROOFS) INTRODUCTION The roof is on top of the building. It has a very important job. It must keep rain and snow out. It also protects us from the sun. There are many different types of roofs. Pitched Roofs A pitched roof is sloped. It looks like a triangle or an A-shape. This shape is good for rain and snow. Water runs down the slope and does not stay on the roof. Snow slides off. Pitched roofs are common on houses. They are usually covered with tiles. Tiles can be