Installing the underfloor heating manifold

We have finally completed the manifold for our underfloor heating system.

It has taken ages to
– design the system.
– fit the design into the space available.
– collect all the required bits of plumbing from various suppliers and retailers.
– puzzle it all together.
– test it.
– resolve the inevitable leaks.Manifold

Alex is usually quite good at producing plumbing that doesn’t leak, but this time, one of the connectors just didn’t want to hold water. Eventually he discovered a slight imperfection on the shiny manifold part and filed it off. That stopped that leak, but started off another one.

After a bit more puzzling and an added plastic o-ring, all is finally well. We are ready to pour concrete on our floors to cover the underfloor heating pipes. It’s a bit of a landmark.

Crossing boundaries

We urgently need to do things differently. The industrial growth society we have built is destroying the natural world. It is no longer tenable. We need to build a new world in the shadow of the old. There are many people across the globe building aspects of that new world. People are rediscovering or reaffirming […]

Celebration: fertile soil for a flourishing world

For several weeks now, I’ve been working closely with soil. I have given it the mulch and fertiliser it needs to thrive. I’ve sown seeds in it and watched baby plants grow. And I have relished eating the first fresh greens. I witnessed very closely how important a good, healthy soil is. As a Druid, […]

A Council of the Wildwood

Sitting in a sacred circle, we listened intently. The spirits of the Wildwood spoke. Each in turn they gifted us with their wisdom, their warnings, their love. Three of us created and held a safe space where people could explore their relationship with a spirit of the Wildwood. Nine others took the journey, staying close […]

Giving gifts to the soil

Working on my raised vegetable bed, I’m learning once again that soil is alive. Every time I dig into the earth, I meet beetles, worms and centipedes. Apart from those, the soil is teeming with micro-organisms and fungi and all sorts of things that you can’t even see with the naked eye. All of them […]

Underfloor heating – it’s just cool

We’re very used to central heating that responds fast when we turn up the temperature. We like our rooms to heat up on demand. With underfloor heating running on cooler water, things are a little different.

Underfloor heating uses water of much lower temperatures than a conventional central heating system. High temperature heating systems run at about 70 degrees C. The water in underfloor heating and low temperature radiators can be as cool as 40 degrees C.

Also, our underfloor heating pipes will be encased in about 20 cm of concrete. It will take a long time for the central heating system to heat up all that concrete and warm up the rooms.Underfloorpipes

That’s part of the point, though. The concrete is a solid thermal mass that will hold on to the heat even when the underfloor heating isn’t on. That means the house will maintain a relatively stable temperature throughout the day and night.

Our heating system won’t be very responsive. If we want to warm up quickly, we’ll need to use our wood burning stove. If we want to cool down, we’ll need to open a window.

The advantage is that it doesn’t take much energy to maintain an even temperature when a lot of heat is stored in the fabric of the house. We’ll be able to keep warm on very little – hopefully just thermal solar topped up with a small amount of wood in winter.

Our heating and hot water will be completely carbon neutral. And that is just very cool.

Making magical connections against the coming storm

“We urgently need to do — and I mean actually do — something radical to avert global catastrophe. But I don’t think we will. I think we’re fucked.” – Stephen Emmott, 10 Billion Those aren’t easy words to read. They’re harder still to take in. Even though I have intellectually known this for years, seeing […]

Heating the house without warming the planet

We hope that we won’t have to heat the Westacre house at all. And if we do, the thermal solar panels should cover most of it.

If all our insulation efforts, and the money we spent on high quality triple glazed windows, work out as intended, our house should be snug throughout the year.

A 16 cm layer of insulation on the outside of the walls, combined with the air tightness we hope to achieve, should cut out any draughts. That should keep all the warmth we generate from cooking, running appliances, and our body heat, inside the house.

Air tightness is great for that, but of course we also need to breathe. We will have to pump fresh air into the house and duct it to different rooms. The air will go through a heat exchanger, sharing the heat of the stale air going out with the cold air coming in. Our heat loss overall should be minimal.woodstack

It’s no guarantee that we’ll be warm enough though. We’ll need to live in the completely insulated house over one winter to work out exactly how much heating is needed.

If we do need to heat the living areas, we intend to do that with hot water from thermal solar panels on the roof. The hot water they generate will go into a heat store, basically a big insulated tank of water that can be pumped around the house when needed. We intend to use it for washing and bathing. And for any heating we need on cold days.

The tricky part, of course, is that when you need heating most, on cold winter days, the solar hot water panels are going to be the least effective. If we find ourselves feeling cold in winter, we’ll use a wood burning stove as extra heating. A stove with a back boiler will also be able to generate more hot water if we need it.

Consequently, we’re building a bit of redundancy into the house. We’re putting pipes for under floor heating into the concrete layer of our downstairs floor in case we need them. We’ll wait and see if we need a wood stove with a back boiler, and how big it needs to be.

And we’re keeping our eye out for free wood, like the dead alder trees Alex’s dad had removed from behind his house. It took us a fair while to chop them up, transport our share to Westacre, and pile them under the leylandii where they will have to season for a couple of years. We are also growing hazel trees for coppicing in parts of the garden.

Wood is a carbon neutral fuel, but if everyone started heating their uninsulated draughty houses with wood, there would soon be a shortage of trees. Insulating the building as much as possible first ensures that we don’t use more than our fair share of trees.

Worth, value, and the cycle of gift giving

Over the last couple of weeks, I have been considering some new ideas for the Westacre Spiritual Centre. I am developing a programme of one-to-one mentoring for younger or less experienced Pagans. The question, as always, is how to charge for that. The whole issue has brought up a host of other thoughts about my […]

Insulating under the floor

Insulation is the main ingredient in our efforts to minimise Westacre’s carbon footprint. If we can retain as much heat as possible within the house, we may not have to heat it at all. To get there, we need to insulate thoroughly, including above the ceilings in the loft and below the concrete floor.

We are adding a substantial layer of concrete to the floors downstairs. They will function as a heat store, helping to keep the house warm and the temperature even.


Of course, if you want your concrete floor to be a heat store, it needs to be insulated from the actual cold and damp earth. Consequently, we have to install a lasagne of insulation layers under the floor. When all of it is done, it will look something like this:

The starting layer is the site concrete. In the part of the house we are working on, that’s nearly 90 years old now, and very lumpy. We had to even it out with sand to protect the first layer of our lasagne.

First of all, we put down sturdy black plastic as a damp proof layer. It is glued to the actual damp proof course of the house. And of course, it’s important this is not perforated anywhere. Hence the sand.underfloor1

On top of the plastic are three layers of polystyrene, to a total of about 22cm. All of that is edged with thin Celotex insulation boards going a bit higher up the walls. It’s all been foamed in at the edges to keep everything in place.

Next comes another layer of clear plastic for protection.

The concrete layer is next. But we’re adding a few more features to that.

A lot of electrical and date wiring will run through conduits under the concrete. And we are putting in the pipes for an underfloor heating system. As we don’t know how much heating we’re going to need, we intend to be prepared for everything.underfloor3

So, on top of the insulation, raised on some bricks, we will be placing a mesh of concrete reinforcement bar (rebar). The underfloor heating pipes are coiled on top of that.

And then we order in the cement lorry. When that day comes, I’ll be sure to get the video camera out. We are hoping for a concrete layer of about 15cm.

The whole thing is levelled off with screed, and eventually we’ll tile on top.

We are investing in staying warm for the long run. When the renovation is finished, we hope to only have to use the underfloor heating on very cold days. It will be fuelled by solar hot water panels, backed up by a back boiler on our wood stove. We’ll only know how well that has worked when the whole project is finished and we’re living in it.