I’ve long wanted to write a blog post titled “Everything I Know About Architecture I Learned from Sailing.” Looks like you’re already on it Lloyd! (Of course Peter Prangnell might have played a bit of a role too. 😉) Fabric First plus Adaptive Control perhaps? Throwing technology at the problem is the architectural equivalent of what we called motorboats when I was a kid: stinkpots.
It’s nice to have a name for how we (try to) manage the temperature of our 100 year old grandma house in the okanagan valley. The single best thing we have done to manage the heat is to put up curtains and bamboo blinds away from the house to stop the walls from getting hot, and then in the winters to use draft dodgers, curtains, and storm windows. It’s not perfect, but it means we can restrict use of our portable, inefficient ac to days that reach 34C+ and nights that don’t go below 25C.
Oh, and as a cavalier owner, lovely to see the late Millie, especially as Millie is my childhood nickname.
I agree with you that PassivHaus is a mistake, and the need for thermal mass, but I do not agree with some of the rest because you are missing many of the fundamentals.
Just for some cred, I have been responsible for building over 100 houses, been involved in building around a further 400, and have won design awards, including an award for eco-homes made of straw bales and rammed earth.
The problems with Passivhaus if that they focus of air-tightness and insulation, because they heat only the air, not the fabric of the building that is usually wood. Not just wood, but wood chips stuck together with toxic glues and treated with chemicals to stop it rotting, so you will be living in a sealed box full of toxic, carcinogenic and gender-bending chemicals. Not good!
I liken Passivhaus to this; supposing you live in a caravan in winter, zero degrees outside, with poor insulation. The fan heater is on full blast and it barely gets to 16*C. Then someone opens the door, all the warm air escapes and the temperature falls to zero.
So you decide to fix it. You talk to the local farmer and he brings over some straw bales, and you encase your caravan in all that insulation. Wow, what a difference! Now the fan heater easily gets it up to 22* and for the first time you feel warm! But then someone opens the door and still the temperature falls to zero, because it is still only the air that is warm.
You are right to discuss thermal mass, but the whole point of thermal mass, like rammed earth or concrete or containers of water, is that IT MUST BE INSIDE THE INSULATION! Then when you heat the house, you heat the thermal mass and that becaomes a massive heat store, far more than the warm air in the building. Now when someone opens the door or window, the warm air escaped but the massive heat store quickly warms up the 'new' air that enters the building, and you don't feel cold.
An example may be you buy an old stone cottage and bring it up to high eco and comfort standards. What you must NEVER, EVER do is insulate the inside of the walls and plasterboard it, because in the long term it will destroy the building fabric. Old buildings, especially stone or brick with lime mortars, rely on a balance of moisture, ventilation and warmth in the walls to keep the mortar damp. If you insulate the inside, the wall will become wet all the way to the insulation, and damage the mortar, even the bricks. And you have made your home like that caravan; all insulation but no thermal mass, so only the air gets warm.
There is much more, but if you want an eco building on the (relative) cheap, I would recommend using lime-rendered structural straw bale on the outside, thick rammed earth floors and internal walls, and a Trombe Wall on the south side with a lean-to conservatory. If done properly, it will barely need any heating beyond the sunshine on the Trombe Wall.
If I’m understanding it correctly, for example, the cloth hangings covering the walls offered little insulation benefit directly but they created a layer of still air that itself acted to some degree as a thermal barrier between the castle’s stone walls and the interior of an occupied space?
GreenBetween 13C-30C (55F-85F) is my mantra, driven by the crucial need to promptly minimize our greenhouse gas emissions. Don't heat above 13C. Don't cool below 30C. Dress warmer or cooler to accommodate the temperature range. That covers the basics at zero cost. With added costs, comfort levels can be improved as per your article. Https://greenbetween.home.blog. ... Don't hesitate to be a climate hero and extend the temperature range. I do. ... OK. I "cheat" a bit. I keep the bathroom at 60F (15.5C) during the heating season - and a bit warmer for showers.
I'm recalling a friend who's home I lived in for 3 years. As the first winter approached, I was acutely aware of his desire to use as little energy as possible. I started the difficult conversation with him of what the thermostat would be set at that winter. We haggled for a while and the highest I could get him to go was 12°. I made it through a few winters like that. It wasn't as bad as I had imagined but it's also not something I would care to do on an ongoing basis. That being said, I'm 61 and I've seen a very clear rise over my lifetime in what's considered "normal" indoor temperature. When I was young I remember 20° being normal room temperature . These days I think most people have it at 22°.
I’ve long wanted to write a blog post titled “Everything I Know About Architecture I Learned from Sailing.” Looks like you’re already on it Lloyd! (Of course Peter Prangnell might have played a bit of a role too. 😉) Fabric First plus Adaptive Control perhaps? Throwing technology at the problem is the architectural equivalent of what we called motorboats when I was a kid: stinkpots.
It’s nice to have a name for how we (try to) manage the temperature of our 100 year old grandma house in the okanagan valley. The single best thing we have done to manage the heat is to put up curtains and bamboo blinds away from the house to stop the walls from getting hot, and then in the winters to use draft dodgers, curtains, and storm windows. It’s not perfect, but it means we can restrict use of our portable, inefficient ac to days that reach 34C+ and nights that don’t go below 25C.
Oh, and as a cavalier owner, lovely to see the late Millie, especially as Millie is my childhood nickname.
Lloyd, I really appreciate your ability to continually rethink previous ideas. We need more of that in the world!
I agree with you that PassivHaus is a mistake, and the need for thermal mass, but I do not agree with some of the rest because you are missing many of the fundamentals.
Just for some cred, I have been responsible for building over 100 houses, been involved in building around a further 400, and have won design awards, including an award for eco-homes made of straw bales and rammed earth.
The problems with Passivhaus if that they focus of air-tightness and insulation, because they heat only the air, not the fabric of the building that is usually wood. Not just wood, but wood chips stuck together with toxic glues and treated with chemicals to stop it rotting, so you will be living in a sealed box full of toxic, carcinogenic and gender-bending chemicals. Not good!
I liken Passivhaus to this; supposing you live in a caravan in winter, zero degrees outside, with poor insulation. The fan heater is on full blast and it barely gets to 16*C. Then someone opens the door, all the warm air escapes and the temperature falls to zero.
So you decide to fix it. You talk to the local farmer and he brings over some straw bales, and you encase your caravan in all that insulation. Wow, what a difference! Now the fan heater easily gets it up to 22* and for the first time you feel warm! But then someone opens the door and still the temperature falls to zero, because it is still only the air that is warm.
You are right to discuss thermal mass, but the whole point of thermal mass, like rammed earth or concrete or containers of water, is that IT MUST BE INSIDE THE INSULATION! Then when you heat the house, you heat the thermal mass and that becaomes a massive heat store, far more than the warm air in the building. Now when someone opens the door or window, the warm air escaped but the massive heat store quickly warms up the 'new' air that enters the building, and you don't feel cold.
An example may be you buy an old stone cottage and bring it up to high eco and comfort standards. What you must NEVER, EVER do is insulate the inside of the walls and plasterboard it, because in the long term it will destroy the building fabric. Old buildings, especially stone or brick with lime mortars, rely on a balance of moisture, ventilation and warmth in the walls to keep the mortar damp. If you insulate the inside, the wall will become wet all the way to the insulation, and damage the mortar, even the bricks. And you have made your home like that caravan; all insulation but no thermal mass, so only the air gets warm.
There is much more, but if you want an eco building on the (relative) cheap, I would recommend using lime-rendered structural straw bale on the outside, thick rammed earth floors and internal walls, and a Trombe Wall on the south side with a lean-to conservatory. If done properly, it will barely need any heating beyond the sunshine on the Trombe Wall.
If I’m understanding it correctly, for example, the cloth hangings covering the walls offered little insulation benefit directly but they created a layer of still air that itself acted to some degree as a thermal barrier between the castle’s stone walls and the interior of an occupied space?
The fabric breaks the radiation of heat from your body to the wall. The layer of air breaks the conduction. its different. Read this https://www.energyvanguard.com/blog/Naked-People-Need-Building-Science
I suspect that you may have seen Kris De Decker’s related article “How to Dress and Undress your Home” in LOW←TECH MAGAZINE. https://solar.lowtechmagazine.com/2025/06/dressing-and-undressing-the-home/
It’s comprehensive but doesn’t deal with mean radiant temperature, which is a big oversight!
He is always terrific, and I hadn't seen that yet! there is also this one from Kris about clothing that is also great https://solar.lowtechmagazine.com/2011/02/insulation-first-the-body-then-the-home/
It would be nice if makers of technical clothing like Patagonia would measure and list their clo values.
GreenBetween 13C-30C (55F-85F) is my mantra, driven by the crucial need to promptly minimize our greenhouse gas emissions. Don't heat above 13C. Don't cool below 30C. Dress warmer or cooler to accommodate the temperature range. That covers the basics at zero cost. With added costs, comfort levels can be improved as per your article. Https://greenbetween.home.blog. ... Don't hesitate to be a climate hero and extend the temperature range. I do. ... OK. I "cheat" a bit. I keep the bathroom at 60F (15.5C) during the heating season - and a bit warmer for showers.
Thank you for commenting Don, I couldn’t remember your name but did remember the green between, I thought you would like this!
I'm recalling a friend who's home I lived in for 3 years. As the first winter approached, I was acutely aware of his desire to use as little energy as possible. I started the difficult conversation with him of what the thermostat would be set at that winter. We haggled for a while and the highest I could get him to go was 12°. I made it through a few winters like that. It wasn't as bad as I had imagined but it's also not something I would care to do on an ongoing basis. That being said, I'm 61 and I've seen a very clear rise over my lifetime in what's considered "normal" indoor temperature. When I was young I remember 20° being normal room temperature . These days I think most people have it at 22°.