Wemmick considers his home a haven away from the harsh reality of London.
In London, Wemmick seems stern and harsh. He is Jaggers’s law clerk, and everything at the Jaggers office is strict and tough. However, Wemmick prides himself on keeping a division between his work life and his home life. His home could not be any more different than his work.
Wemmick himself seems to be a dry and boring person at first.
Casting my eyes on Mr. Wemmick as we went along … I found him to be a dry man, rather short in stature, with a square wooden face, whose expression seemed to have been imperfectly chipped out with a dull-edged chisel. (Ch. 21)
Pip notices that Wemmick has an interesting personality underneath the hardness. He is definitely more talkative than Jaggers. Therefore, he begins to spend more time with Wemmick, and even asks to hang out with him. He gets invited to Wemmick’s home at Walworth.
Wemmick loves his house. He is very proud of it. In fact, he built it mostly himself. It is an extraordinary house.
Wemmick's house was a little wooden cottage in the midst of plots of garden, and the top of it was cut out and painted like a battery mounted with guns. … I think it was the smallest house I ever saw; with the queerest Gothic windows (by far the greater part of them sham), and a Gothic door, almost too small to get in at. (Ch. 25)
The house looks like a castle, and even has guns set off every night and a real flagstaff. He has his own gardens and small livestock. All of the eccentricity is designed to keep his elderly father, the Aged Parent, happy.
It is almost like Wemmick has to make his house completely different from everything that Jaggers is, and make his life at home completely different from his life at work. He takes the stern, dark, harsh life at work and contrasts it completely with whimsy and light at home. He creates an escape.
No one is allowed at Wemmick's house other than Miss Skiffins, his girlfriend (whom he marries) and other close friends. Jaggers knows nothing about any of it, and when Jaggers finds out Wemmick is mortified. Wemmick had explained to Pip that he tried to keep his two selves separate.
“Mr. Pip,” he replied with gravity, “Walworth is one place, and this office is another. Much as the Aged is one person, and Mr. Jaggers is another. They must not be confounded together. My Walworth sentiments must be taken at Walworth; none but my official sentiments can be taken in this office.” (Ch. 36)
Wemmick cares about two things: portable property and home. Home is sacred. It is his way of keeping a balance in his life, and pushing out the cobwebs of Newgate and Jaggers.
Many people struggle with leaving work at work. Wemmick does it by creating a mental barrier and making sure that his two selves- the work self and the home self- never merge. Pip changes all of that, of course, when Wemmick befriends him. Wemmick breaks his unbreakable rule in becoming friends with Pip, and his relationship with Jaggers is altered because of it.