“… it’s not the materials but the builder that makes a building green”
Clark Snell,Building Green
I first saw a preview of Building Green (I think it was on Google Books) and wasn’t impressed by it. Then Ina & Sabin introduced us to it and loaned us their copy and I was really surprised by it. I have been immersed in the book and gained a lot from it. It doesn’t mention hemp-construction in any way. It does cover many other green building techniques and materials. But most importantly it is written with an appeal to common sense and with plenty of educational images which demonstrate that common sense really does work. Though I will probably not be using any of the building techniques mentioned in this book directly, I will be using a lot of my own judgement to make design & engineering choices and relate to solutions offered by professionals.
To me, the spirit of the book is best embodied in this quote which I have frequently brought up in conversations since it came to me:
“One the biggest sources of our environmental woes is the constant and polluting movement of humans about the planet. To create a sustainable lifestyle, we need to stay put more of the time and derive more of our social, physical and spiritual sustenance from our own backyards. For example, it takes a longtimeto build healthy soil to grow food; to build a network of friends and compatriots that will be the basis for community; to nurture the trees and other plants that will be part of a house’s cooling strategy. These things simply won’t happen if you aren’t sufficiently seduced by your home to stay there for the many years it will take to turn it into a real place that nurtures both its inhabitants and the environment. A “green” house, then, needs to be beautiful, a place that is as hard to leave as a lover and as unthinkable to neglect as your own child.”
As someone who has lived in rented apartments and houses all of my adult life and am now heading towards creating what may be our first and only house in this lifetime I can completely relate. I have been a tourist in most of the places I’ve lived – never quite made it to become a resident of the place.
The people of Green Building Store (UK) have generously produced and published a freely available online movie about some of the challenges they faced in a Passivhaus construction project in the UK. Though I am wary of taking on the Passivhaus standard as is (reservations I’ve written about in posts about Passivehaus and Rural Studio) I am also trying to be careful not to pour the baby out with the water. There is a lot of common sense in Passivhaus and much of it is excellently communicated in this movie. You can view all the parts here or possibly start with this embedded video and then continue to each consequent part:
So, with much curiosity and interest I watched the movie (reviewing some of the chapters numerous times) and made some notes of things that I hope to incorporate into our building process. This list does not include the core-issues of Passivhaus construction (insulation, minimal thermal bridging, air-tightness, ventilation and passive solar gain) which deserve careful context and consideration – especially when it comes to hemp-lime construction which introduces unique qualities to both the construction process and the resulting structure.
Design & Details
It is invaluable to spend time designing and paying attention to details before the actual construction process. Construction is an established process and skill which carries with it a taken-for-granted attitude. Professionals have a way of doing things and will prefer to do things the way they’re used to doing them – which may lead to cutting corners in design and to on-site improvisation.
This can be destructive in a project where new standards of building, new materials and new techniques are involved. Taking the time to plan things in advance, to drawing diagrams & making calculations creates a thoughtful path towards a desirable result. Of course it is inevitable that unforeseen challenges will arise during construction and that some changes and improvisation will be required – in which case a plan gives some indication of how far you’ve deviated and what you need to do to get back on track.
Special attention should be given to details. I’ve been working on a wall-to-floor detail for weeks – compiling all the information and knowledge I have come across, reconsidering it in the context of hemp-construction, our house design, minimizing costs, minimizing the use of concrete and relying on locally available materials. There is no ready-made template for what we are doing, there are many options to choose from, there are many considerationt to incorporate. We could take the easy path and hire foundation contractors and let them do their thing – but that would lead away from the kind of warm, pleasant, ecological and efficient house we hope to live in and bring us to the standard cold and humid house that contractors have been building in Romania for may years.
A typical construction process tends isolate and compartmentalize knowledge and skills. We would consult with an architect to design our house. Then we would pass the plans to an structural engineer who would need to figure out how to support our house. Then we would pass the architectural and structural engineering plans to a heating engineer who will try to provide an adequate heating solution within the existing constraints.
This kind of approach can lead to an inefficient process and an inefficient house. A good engineer can provide a structural solution to meet almost any need – but at what price? How much extra work, materials, construction effort and waste may be required to implement the engineered solution? Similarly a heating engineer can theoretically heat any space – the question is how expensive and complicated will the system be and how much energy will it consume? This is a brute force approach.
We are trying to put together a team that will work together during all phases of the project. We’d like everyone to be there to provide input at every stage of the project. We’d like the architect to provide input on choosing good land and on siting of the house on it. We’d like the structural engineer to make suggestions on architectural decisions that may lead to simpler and more efficient construction using less materials. We’d like a heating-engineer to review the size of our spaces and to make suggestion that may improve the energy-efficiency of the house.
It takes integrated and out-of-the-box thinking to create the kind of integration that leads to a house that facilitates an “eco” existence.
I have been wondering about how to go about properly insulating openinsg like windows and doors. The movie offered some very useful tips about these issues and these are the ones I noted:
Windows should be placed at the center (depth) of the wall.
Windows should open inwards – placing the thicker part of the frame on the outside for better insulation.
Special sealing tape (such as Pro Clima Contega FC) should be applied between the rough structural opening and the internal wall and then covered by the the internal render.
Special sealing tape (such as Pro Clima Tescon) should be applied between the window frame and the rough structural openings.
A concrete slab should not extend to the door opening to prevent heat loss through it.
The door opening slab requires an insulated and weather resistant material (such as fiberglass).
A big thank you to the people at Green Building Company. This movie has been very educative and helpful.
We want to have a really pleasantly warm house when it gets cold outside. Building with hemp insures that we enjoy a wonderfully insulated home. Now we need to deal with heat – which includes both environmental heating and water heating.
In typically built houses which tend to be cold when it gets cold outside it’s more a brute force challenge. With an ecological house it is actually more complicated because it’s easy to design a system that overheats the house. We still don’t have a clear picture or understanding of our heating needs – though we are working at it.
In the meantime I wanted to share with you some great resources that we are using to educate ourselves:
Stoves Online (UK) – it s great resource for learning about the different elements that make up a heating system with a very rich offering of solutions if you happen to live in the UK.
Boiler Stoves (UK) – seems like a sister website which specifically explains how boiler stoves work and can be incorporated into a smart and efficient heating system.
Radiant Design Institute – though not an appealing website has a lot of really well-grounded and useful information I believe can be very useful especially to do-it-yourselfers.
I’ve been struggling to understand on if/why a concrete slab is necessary. I completely understand the need for footings and foundations – but slabs are not that clear. It’s somethinge eveyone seems to take for granted … but I am undecided on it.
Anyways … I did come across this excellent free eBook generously published by Cement Concrete & Aggregates Australia – which seem to have many more freely available resources on their website. IF we do end up building with concrete foundations (yep – that’s an if!) we will probably hire a contractor for it – it’s one of those jobs where DIY doesn’t seem to have much point/value. Even so – this eBook is a must read because at least I know what to expect, to relate to engineering/design choices and to make sure things are getting done right on site.
I will probably be spending some time with their resources – I’ll let you know if I find anything interesting 🙂
I’ve been spending the last few weeks immersed in reading about wood-framing. I’m really enjoying the experience of feeling that it really is possible to self-build a home. It’s logical, straightforward and building with hemp simplifies it even more.
I recently came across these sample PDF plans of an eco-house from Studs – a UK timber frame design company. I am happy to say that it isn’t all giberish to me anymore 🙂 I still can’t read it all – and some parts are a bit overwhelming – but I think it’s good practice to start looking at such plans. They provide house design ideas, they teach structural lessons and they prepare you to communicate with other professional which we expect to be doing.
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.