When rating this book I was torn between 2 and 4 stars. In the end I decided to give it 2 stars for it's entire lack of readability.
House of Leaves is definitely the most exhausting book I ever read. The author tells several stories that overlap each other. The central story is about the House. On it's outer wall is a door that should open into the garden but instead leads into a long, dark, seemingly never-ending corridor which turns out to be a labyrinth which can change its size and cleans itself of all intruders. The story about the House is told by Zampano, an old blind man. After his death the book is found by Johnny Truant, a young drug addict with a bad childhood whose mother is in a psychiatric clinic.
The author tries to make the whole story look true by giving prooves: there is a ca. 200 page long appendix. There are also masses of footnotes giving sources. Most of these sources were invented however.
The lack of readability comes from the author's very special style: The story about the House is written in a very matter-of-fact, reportage-like style. Also, this central story actually is the shortest part of the whole book. The author sometimes writes page after page about different topics: architecture, physics, religion, Greek mythology, language, psychology etc. Often the strcutre is like this: one paragraph of the actual story, excursus to a topic touched in this paragraph, footnote giving a source and a further excursus, footnote on this footnote telling Johnny's story. So after having read 10 pages of something else you can finally go back to the real story.
The author tries to make the labyrinth visible by using this method. Sometimes he also uses loops: if you follow all the footnotes eventually one footnote will put back in the text again so that you'll finally be lost in the labyrinth.
Sometimes the text is also written in an experimental fashion: you have to turn the book round to be able to read it. Or there are only a few words on each page (I actually liked that because I able to make faster progress :)
All of this is very interesting. But only for about 400 pages. After this the book started to really annoy me.
The book also was very different from what I expected. I have often read here on Goodreads that it is quite creepy. The central story actually is. But all the footnotes and the excursus extremely take out speed and suspense. So if you are looking for a horror novel that will really scare, House of Leaves definitely is not the thing for you.