Location of Mr. Hyde's house?

From the text:

No, sir, I make it a rule of mine: the more it looks like Queer Street, the less I ask.’
‘ A very good rule, too,’ said the lawyer.
‘But I have studied the place for myself,’ continued Mr. Enfield.’ It seems scarcely a house. There is no other door, and nobody goes in or out of that one but, once in a great while, the gentleman of my adventure.