The above line has been taken from the poem The Silver House written by John Lea.
1). In the poem, "the silver house" implies the silver moon in the lovely sky.
The two weeks to build it up means the weeks required for the moon to complete its journey from the new phase to the full moon phase.
The two weeks to pull it down implies the two weeks during which the moon keeps decreasing its size.
2). The poet says that there is a lonely man who lives in the silver house.
3). The two pairs of rhyming words are blind - find and bare - there.
4). It takes two weeks to build it up and two weeks to build it down.
I hope that helped.