Wemmick works with Jaggers, who is a rather formidable man who works with all sorts of interesting and even sometimes unsavory characters. It is dark there, alarming because of the strange artifacts, and Wemmick is very matter-of-fact and professional, keeping his distance from any personal relationships. His workplace is cold, aloof, and feels unfriendly and impersonal, and Wemmick himself is very businesslike and task-oriented there.
His home, on the other hand, is almost the opposite of all of these things. It is warm, inviting, homey, and incredibly unique. It is well taken care of, and there, Wemmick is almost an entirely different person. He is warm, affectionate, affable, and shows his true congeniality and happiness. It is a quaint and unique place, each and every item of decor showing individual character that is all his--not a hodgpodge of random meldings from clients, like his workplace is.
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.
"My own doing," said Wemmick. "Looks pretty; don't it?"
As the novel continues, Wemmick's workplace continues to be a place of mystery and confusion, almost a symbol for Pip's dark journey through the shadowy circumstances of his wealth, and his confusion over his situation. Wemmick's house, on the other hand, becomes more and more a place of warmth and refuge, a prime model for a happy home, something that Pip lacks in his new life. It symbolizes all that can be found if you are with those that you love, in a place that you love. The contrast is stark, and one worth noting in the novel.
I hope that helps a bit; good luck!