Firmament is heaven

14 And God said, Let there be lights IN the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years: (The lights IN the firmament are the sun, moon and stars)

15 And let them be for lights IN the firmament of the heaven to give light upon the earth: and it was so.

17 And God set them IN the firmament of the heaven to give light upon the earth,

20 And God said, Let the waters bring forth abundantly the moving creature that hath life (Fish), and fowl that may fly above the earth (Birds) in the open firmament of heaven.

above the Firmament is a throne

Isaiah 14:

13 For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God: I will sit also upon the mount of the congregation, in the sides of the north:

Exodus 24:

10 And they saw the God of Israel: and there was under His feet as it were a paved work of a sapphire stone, and as it were the body of heaven in his clearness.

Isaiah 40:

22 It is He that sitteth upon the circle of the earth, and the inhabitants thereof are as grasshoppers; that stretcheth out the heavens as a curtain, and spreadeth them out as a tent to dwell in:

Job 22:

14 Thick clouds are a covering to him, that he seeth not; and he walketh in the circuit of heaven.

Psalm 19:

6 His going forth is from the end of the heaven, and His circuit unto the ends of it: and there is nothing hid from the heat thereof.

There is no space.

Water ABOVE the firmament:

Genesis 1: 

7 And God made the firmament, and divided the WATERS which were UNDER the firmament from the WATERS which were ABOVE THE FIRMAMENT: and it was so.

Lights IN the firmament:

Genesis 1:

14 And God said, Let there be LIGHTS IN THE FIRMAMENT of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years:

Windows of Heaven:

Genesis 7:

11 In the six hundredth year of Noah's life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened.

Deuteronomy 8:

7 For the LORD thy God bringeth thee into a good land, a land of brooks of water, of fountains and depths that spring out of valleys and hills;