It seems that Clark & Tim, the guys who wrote Building Green, moved in the Passivhaus direction. They have a project called Nauhaus where they are attempting to bring together their past experiences with the Passivhaus standards.
I believe, as I have written before, that the Passivhaus standard is not a practical nor sustainable form of construction – though there are some excellent and applicable ideas and inspiration to be drawn from it. The Nauhaus was built with hemp, which from the theoretical (at this point) knowledge I have gathered simplifies, ecologizes and reduces costs of many construction aspects. Yet because of Passivhaus standards Nauhaus also reintroduces many complications which I find … uninspiring. Just this morning I was reading their chapter on building a green roof, then I came across the massive, industrial insulated crane-lifted panels they used in the Nauhaus project. Though I can appreciate their efforts to move forward and improve … it feels to me like they took a wrong turn somewhere … I think Passivhaus had something to do with it.
Amongst the information on their website is an educational set of posts with images showing the contruction chronology – from foundations to a completed building. At this point in my education, these documented processes are extremely useful and rewarding. The chronology starts at the end of this page – from where you can scroll up and forward in time to see the project progress.
My main take from these images is on some thoughtful tricks on how to efficiently prepare and install formwork for the hempcrete as you can see here and here:
And also this super-simple ingenious carpentry lesson from Tim – as he creates a simple tool for measuring and placement of formwork from here.
Wouldn’t it be ideal if you could grown your own hemp and then use it to build your home? 1 or 2 hectares of hemp stalk is potentially all you need to harvest enough building materials to build a house. Imagine that – growing your own house! … but it isn’t a simple thing to do.
The hemp plant has four elements: seeds, leaves, fibers and a wooden core. The part you need for construction is the wooden core – also called the hurd or shiv. Separating it from the other elements of the plant requires effort. You need to grow the hemp, deffoliate it (remove the leaves) before harvesting, harvest or remove the seeds, harvest the stalk, let it ret (start decomposing so that the fibers can be separated from the hurd) and then decorticate it.
This finally step of decortication seems like the greatest obstacle – this is the process of separating the fiber and the wooden core. It can be done either through massive manual labor (of which I don’t yet have all the details – but it involves collecting the harvested stalks into small bales and then beating them to separate the fibers and wooden core) or in an industrial process. The indutrial process is usually designed to extract the fibers, the actual wooden shiv is simply a left over of that process.
It would be so much easier to grow your own construction hemp if decortication could be avoided – and this may be possible but my understanding is that it depends on the climate you live in. This research paper on Hemp-Concretes claims that it is possible to create hempcrete using both shives and fibers – BUT it is important to note that the research focuses on the structural aspects of the resulting hempcrete. It does not address the effect of fibers on insulation and breathability of the hempcrete.
Introduction of fiber to the hempcrete mix can cause humidity problems. When fibers are clumped together they tend to draw moisture and that is not something you want to happen in your wall. According to Steve Allin it is possible to add 5%-15% of fiber to the mix but not much more. This may be less of an issue in a hot and dry climate – but otherwise the risk seems unwarranted.
Maybe when the hemp industry matures it will be possible to cultivate stalks with very little fiber and a massive wooden core – which could then be used in whole? For now though it seems that self-grown hemp is not a feasibly reliable option for construction unless you have the means to decorticate it.
There is only one book (worthy of being called a book) I know of (in English) – Building with Hemp by Steve Allin. It isn’t the one and only book you will need to actually build with hemp – but it provides the best overview, explanations and images I’ve encountered so far on doing so. It touches on many hemp-effected aspects of construction. You will still have to do a lot more inquiring and apply your own common-sense but this book will be an excellent road-map for you on your journey.
Last week we met with two inspiring organizations with whom we hope to collaborate in the process of creating our home here in Romania.
Habitat for Humanity Cluj
The first meeting with with Habitat for Humanity Cluj (English website, Romanian website) who’s mission is to provide decent housing where currently housing conditions are very poor. Here in Romanian they have a few house templates that they can build in a few weeks. They organize volunteers from around the world to come and partake in a quick and efficient building process. They also provide home owners with a zero-interest loan at very small monthly payments (over as long as 20 years) to fund the costs of construction materials.
Our hopes are to both gain from their building experience here in Romania and to offer a shared learning opportunity on the benefits of building with hemp. We believe that hemp-lime construction can be a wonderful alternative with the benefits of simpler construction, better housing (insulation, air quality, durability) and ecological. A win for the organization, for residents of their houses and for the planet.
Our second meeting was with EcoRuralis (English website, Romanian Website) who’s mission is to support traditional Romanian peasants (who represent ~50% of Romanian population) in the face of external forces of industrialization and commercialization (mostly originating from the EU) that threaten their survival and prosperity.
I realize that mission statement may sound petty and remote to non-Romanians so let me give you an example. It is now absurdly illegal for Romanian peasants to sell their traditionally developed and evolved seeds (over hundreds of years). Legal and commercial standards are pushing to replace traditional seeds with genetically modified industrial seeds. Such measures, together with beaurocratic hurdles required to selling their crops in local markets threaten not only their existence but an entire tradition of agrictultural knowledge.
A Peasant Meeting
EcoRuralis were extremely pleasant and generous with us. We immediately signed up as members and over the weekend they invited us to a member-meeting which took place in Calimenste (a 6 hour bus ride south of Cluj-Napoca). Not only were we welcomed in no-questions-asked, they also covered all the expenses in getting to and partaking in the meeting. We had a wonderful time and met inspiring people.
It is so exciting and comforting to know that we have access to everything we need (from knowledge to seeds) to create up our own farm. Though we are currently focused on the construction aspect of our home we are also on our way to becoming peasants and taking up healthy traditional farming.
Another interesting shared interest is hemp-construction. Hemp was once a popular crop here in Romania and we hope it will be again. Everyone was very curious to hear more about hemp construction. We can’t wait to invite them all to see when the house is actually built and then to be our guests and experience what a wonderful quality-of-life it can afford.
Everyone was so kind and so generous. With some translation help I said to them that after almost 40 years of life I am for the first time beginning to feel I am at home.
We just got back from a meeting at the school of architecture in Cluj. It was a good meeting with some followups to look forward to. But we did meet with some skepticism – “ecological building is a fashionable thing” … I agree that there is a lot of fashion in ecological building – even intellectual/academic fashion. I couldn’t possible put it better then George Carlin did:
But, I also think it’s important to be able to discern between the bullshit and the real shit. Ecological building should have direct impact on quality of life – otherwise it really is a fashionable indulgence. So I thought to take this opportunity to share some of the things I consider to be ecological in the context of building a rural house in Romania.
My general impression of homes in Romania (actually Israel too!) has been that they are cold in winter (public spaces are generally much warmer then homes I have visited). This is a combination of poorly insulated homes and fairly expensive fuel resources.
In cities gas is the primary source of heating energy – it is very expensive and building-blocks built of concrete are poor heat containers. We are struggling to keep our gas costs under control and can just manage to keep the apartment at 19-2o degrees celsius.
Village homes are usually poorly insulated (despite super thick mud-brick walls) and even though firewood is relatively cheap, it is expensive when you live on what you can grow … and you can’t grow money. So those that do have fire-wood used sparingly – again, just enough to keep out the cold.
Hemp is said to be one of the best insulating construction materials. This means that the same quantity of fire-wood that a village home uses ine year to just-barely keep the cold out can be sufficient for keeping the same house comfortably warm for 2 years (if not more!).
I’ve mentioned before that almost every apartment or house I’ve visited in Romania suffers from humidity problems. Humidity is locked inside the house and it’s walls (you have to see it to believe it – water running down the windows and accumulating in pools on the window-sills). It turns into mildew which leads to respiratory problems.
Hemp is also said to be a healthy building material. It creates a permeable wall that absorbs excess moisture on the inside and releases it on the outside. It does this without any insulation or sheathing materials. It is a natural quality of a properly built and well ventilated hemp-masonry house.
Self Grown Homes
Romania used to be a major supplier of hemp-fiber – which means that the land here is good for it. As a rule of thumb one hectare of land yields enough crop to build a house. Oh and hemp requires no herbicides or pesticides, kills weeds and renews the land in which it grows. Oh and it is said to have huge potential in world markets for zillions of applications. Oh and its seeds can be used for food and oils which are magically healthy.
Almost every Romanian farm has vast farm lands – which means that most Romanian farmers can potentially grow the hemp they need to build/rebuild their homes.
Simple to Build
Hemp masonry is poured around a wooden frame – which a small group of people with basic coordination and tools can build in a week or two. Romania is gifted with vast amounts of excellent and afforable wood.
Hemp building requires the most rudimentary frame building skills – many framing complications involving insulation and sheathing are completely obsolete do to the nature of hemp construction.
Bringing the Toilet Home
Our new friends, Ina and Sabine, eloquently described the challenge of reviving the image of village homes in Romania “Bringing the toilet – a freezing outdoor shack with a hole in the ground – indoors”. The ecological implications of technologies (they are so simple – that calling them technologies, though true, can be misleading) such as dry-compost make this easy and afforable to do. Running water is used to evacuate waste from the home and then a simpleto-install and super-easy-to-maintain mechanical system separates water and waste and converts the waste into dry and usable compost. So much cheaper and easier then digging a hole in the groun and installing a sceptic tank that needs chemicals, can demand unpleasant maintenance to run and a periodic evacuation service.
So, All Fashion Aside …
We are still beginners when it comes to ecological building – but we are committed to this path. We have a very limited budget to create our home. A limited budget comes bearing gifts of simplicity – complicated, expensive indulgent technologies are just not an option. Ecological means simple solutions, many of which are do-it-yourself (or do-it-with-your-friends), based on and respectful of natural available resources.
That’s it, direct simple things that come together to make life good.