1. He built a house with straw.

2. He built a house with straws.
3. He built a house with wood.
4. He built a house with woods.
5. He built a house with brick.
6. He built a house with bricks.

(Which one is right? Do I have to use a singular form or plural form? Can we use 'out of' instead of 'with'?)

You may use "out of" in place of "with".

#'s 1, 3, 5 and 6 are all correct usage.

bricks

The correct sentences are:

1. He built a house with straw.
3. He built a house with wood.
5. He built a house with brick.
6. He built a house with bricks.

In these sentences, we use the singular form of the material to describe what the house is made of. For example, it is "a house with straw" or "a house with wood." The plural forms, "He built a house with straws" or "He built a house with woods" are not grammatically correct because we don't typically use the plural form to describe the material that something is made of.

Regarding your second question, it is more common to use "with" instead of "out of" when describing the materials used to build a house. However, using "out of" is not grammatically incorrect. So you could say "He built a house out of straw" or "He built a house out of brick." It is more a matter of personal preference and style.