Please click here for the website of Mr Jorg Ostrowski of the University of Calgary, who is an architectural expert in tulou. He presented his knowledge on tulou at the Toronto Hakka Conference 2012.

I'd like to promote the link to a paper published by Dr Keith D. Lowe 罗金生 of the Tsung Tsin Association of Ontario:

Lowe KD. Heaven and Earth—Sustaining Elements in Hakka Tulou. Sustainability. 2012; 4(11):2795-2802.

The paper is published by the Multidisciplinary Digital Publishing Institute (MDPI) on this page on their website. From here you can download a PDF of the paper for free. I have already learned something new from the first page - that I was using the term 'tulou' to mean the roundhouses when in fact it can refer to buildings of other design as well. Hope you enjoy finding out a bit more about our Hakka architecture.