Research needed to build: Conservation(Economy)
Purpose: Allows one to store more resources.
Build in more then one town: Yes, will want them to increase storage in each of your town/colonies
Soft Cap: lvl 16 Can build higher but after 16 the cost is greatly increased.

General Information regarding the WareHouse

Lets take a look around the window from the WareHouse's view(once you click on your on the Warehouse)

On the left side of the screen you will see



Here you can see how much materials will be needed to upgrade and how long it will take. Also you have the option to demolish the building as well. Clicking demolish will give you a confirmation screen showing how much resource you would recover. This option is helpful for when you want to abandon a colony and recover some of the luxury resources and wood.

Also on the left side you will notice:



Here you can see how many resources will be keep safe from pillaging at the next level of the warehouse.

Now in the main area you will see the follow:



This give you vital info on how much you can store safely, how much is currently lootable, how much of each you have in total and finally, how much you can store maximumly.

Misc Info

Lvl 1 WH needed for 1 colony
Lvl 5 WH needed for 2 colonies
Lvl 9 WH needed for 3 colonies
Lvl 16 WH needed for 4 colonies
Lvl 18 WH needed for 5 colonies
Lvl 19 WH needed for 6 colonies
Lvl 20 WH needed for 7 colonies
Lvl 21 WH needed for 8 colonies