cob resources

Resource Review –

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We’ve been looking into several resources on cob building and learning to build with cob, and one of the best resources we’ve found so far is Alex Sumerall’s We’ve read his book, signed up for his online cob building workshop, subscribed to his blog, and most recently, attended his free webinar, “Introduction to Cob Building”.

Alex has also been incredibly helpful in providing specific answers to questions we had on cob building. He’s responded to every email promptly and with great detail. It’s definitely a bonus having quick access to the author and teacher of the course!

Some of the free resources Alex offers are webinars, blog posts, and articles, as well as links to more information from other cob experts. However, if you’re ready to dig into (pun intended) more detail, he offers an intensive and in depth course on cob building that’s as close to a workshop as you can get without actually having to invest the time and money required to go to one (although he offers the workshops as well).

The course is presented in video format, a combination of footage from his build sites and PowerPoint presentations on more of the “classroom” type knowledge, and includes printable notes and a Q&A comment section for each lesson. It’s a 12-month course, although I believe only 5 months are up on the website right now, but that could be because we don’t have access to the later lessons yet. Each month is broken down into basically what you would be doing for that month on your own dig site, at least that’s how the first month has been for us. Alex includes case studies, monthly Q&A reviews, and instructions for different design options, including round and square foundations and walls.

He has two books, Build a Cob House: A Step-by-Step Guide, and Cob to Code, which covers building codes and their impact on cob housing. The first book breaks everything down, truly step by step, with instructions and photos of each part of the building process. The second book I have yet to read, mostly because building codes don’t apply in our area.

Casey and I both attended the free webinar today, and I really hope Alex plans on hosting more of these! It was informative and included a Q&A at the end. Unfortunately, Alex received so many questions that he wasn’t able to answer the several I submitted before the end of the webinar. I sent him a quick email, and once I’ve received the answers, I’ll update this post to include them.

UPDATE: Just seconds after I finished this, I received a response from Alex. Thanks for the quick reply!

Q: I’ve read in your book and Becky Bee’s book that you shouldn’t use hay, but instead use straw. However, Bee also mentioned that many local grasses and reeds can be used. Isn’t hay a type of grass? And if used and it does sprout, can you just let it sprout and pluck it before plastering? We don’t have good sources of straw in SE Oklahoma, but we have tons of hay!
A:  Yes, you could let the hay sprout and then just go from there. Straw is always best if you can get some though. It has stronger tensile strength.

Hay is a pre-harvest crop. Straw is post harvest, and doesn’t have the living organic parts left that can easily decay.

Q:  Can you use cob for roofs?

A:  Cob can’t be used for roofs since it’s too heavy. The only way to use earth materials for a roof is to do a dome or vault using either adobe blocks or superadobe, but these are quite technical to construct.

Q:  Can you use cob for tubs or sinks?

A:  You can sculpt cob sinks, tubs, showers and then plaster them with a lime render called tadelakt. It is waterproof.

Q:  [Regarding a special Alex ran during the webinar] Can we get the cob plans even though we’ve already registered for your course?

A:  And yes, I’ll attach the plans for you too!

So if you’re looking for more information on building with cob, check out And the special Alex is running includes both of his books and two sets of cob building plans, one for a house and one for a garden wall. It’s a great value, all included in the current subscription price for the online course.

Have you found any great resources you’d like us to mention or review in upcoming posts? Add them in the comments below, and we’ll be sure to check them out!