This is a great build if you're looking for a home with adequate storage!

You will need:

81 pieces of glass

A tool to break stone or gravel

A lot of mental endurance (gravel WILL be annoying and there is no way to stop this other than to break the 81 block of gravel where you will put the glass (UNDER WATER))

4 – 6 torches per room

Let’s get to the steps on building it. 

First, find an ocean with a flat sea floor near land for easy access to the base and land (this build looks really good in a frozen ocean). Now we get to making the room.

• Break a 9x9 room 4 blocks beneath the layer of gravel with the gravel being the layer you will put the glass, making the glass one level higher than the room.

• Place the glass on the level where the gravel was so that water stops pouring into the room.

• (IF YOU HAVE NOT ALREADY BROKEN THE GRAVEL) Break the gravel that has fallen onto the floor of the room you have mined.

• After this, place torches in the corners and middle of your room so that the torches face each other (this is purely optional, you can choose what layout the torches go however if you want to make more rooms then this is the best layout).

Now with this done, you have completed a room. If you wish to make more rooms then read on.

If you’re choosing to read on then follow these steps to make more rooms.

• (Break a 3x2x4 gap in the middle of a wall (make sure to place blocks at gravel level so that water does not pour in)) OR (Make a 5x2x4x5 gap in the corner of your room so that an 8x8x4 room would be made by doing the same on the other side of the gap. This will make each corner of the 8x8x4 a possibility for a room ((mine out 9x9 rooms on each corner of the 8x8x4 making it so there is a 2 block wide, 4 block tall wall between each 9x9 room) (I know this is confusing but follow carefully). If followed correctly you should have 4, 9x9 rooms all connected by an 8x8x4 room in the middle of them with a 2 block thick wall between them)).

With this confusing base built you should have 4, 9x9 rooms that can be used for storage or housing, and you can repeat one of the processes above to create more rooms. 

(I’m sorry it was confusing)