Trees make themselves out of the CO2. A growing tree absorbs CO2, an already grown tree is effectively neutral, and a dead tree releases the carbon when fungus decompose it.
If you cut down a tree and turn it into a house that lasts for 200 years, then you've sequestered that carbon for longer than the tree likely would have.
Note that this really depends. A quick growing tree wouldn't have lasted 200 years, but there are tree species in which individuals have been around for longer than recorded human history. I don't think any of them occur in the right part of the world, but if they did it'd be easily possible there's a tree which was once pissed on by a mammoth (~4000 years ago), and yet is still alive now.
England has some trees that are definitely hundreds and probably a couple of thousands years old. And England isn't exactly the ideal place to be a tree, it's small, heavily populated and the people who live on it cut a lot of trees down either for firewood or to build things. I'd be surprised if Canada lacks 2000 year old trees.
If you cut down a tree and turn it into a house that lasts for 200 years, then you've sequestered that carbon for longer than the tree likely would have.