Tuesday, 25 October 2011

DECIDED! Timber frame with DIY SIPS construction

A modern timber frame home with exposed posts and beams
It has been while since the last post and much has happened on narrowing down the construction method. I am now ready to announce the final construction decision and the rationale that went into making it!

The ecological concept drove me to research a wide variety of materials. I have been through straw bales, earth houses, papercrete, and just about everything else on the search for the best construction methods. I have settled on locally sourced timber. Where timber production is highly regulated it is perhaps the most carbon-neutral ecological material. The timber for my house will be sourced within one prefecture of the building site and will be Japanese cedar or "sugi".

Many houses are today made from wood, but today a wooden house normally means that the house has been built using the 2x4 method (also known as platform framing, stud wall or stick construction). Houses built in this style are strong and reliable and when well built can offer good insulation values. The disadvantage with building in 2x4 (or the larger 2x6) is that the structure retains no cultural or historical integrity--it could be a house from anywhere in the world.

The reason I went for a "timber frame" house rather than 2x4/2x6 was that it allowed me to preserve some of the character of Japanese timber framing style (again, 2x4 is a generic modern style made for structural integrity with no particular historical tradition).

For fast reference and those who are particularly interested, the biggest influence over the final decision on how to build the house was from Ted Benson's book, The Timber-Frame Home: Design Construction Finishing. The book Natural Timber Frame Homes is also a great read to get one enthusiastic about the style and its merits.

Benson's book explores the history of timber frame design as it has evolved across several parts of the world

Choosing to build in the timber frame method is also an advantage when it comes to Japanese building regulations. Essentially, unless going for an approved pre-fab or log-house company product, the easy options available to the home builder are 2x4, concrete or timber frame construction (zairai). Zairai is the most common construction method in Japan, and represents the most traditional style timber construction (although 2x4 is catching up fast at the time of writing).

With a Japanese timber frame on the inside of the house and insulating panels wrapping around this frame, the house will show off it structure to the inhabitants--all the posts and beams will be visible features of the interior living space. For an idea of how this looks do a google image search on timber-frame homes.

So, that's it, the house will be a timber frame with insulated panels wrapped around the outside in the Benson style. I will post more over the next weeks about the exact materials and sourcing. Thanks for reading!


  1. Benson's book is most certainly an interesting read. His methods can be criticized today however I am a big fan. I personally like the Japanese methods of designing and building, so I really enjoyed reading this post. If I were to build my own bathroom, I would use deca design flooring - I have used them for a while now and I couldn't say a bad word about them. Much similar to how I feel about Benson!

    Thank you for sharing this.