| Good morning. |
| In the last few lectures, I've been talking about the history of domestic building construction. |
| But today I want to begin looking at some contemporary, experimental designs for housing. |
| So, I'm going to start with a house which is constructed more or less under the ground. |
| And one of the interesting things about this project is... |
| that the owners - both professionals but not architects - wanted to be closely involved, |
| so they decided to manage the project themselves. |
| Their chief aim was to create somewhere that was as environmentally-friendly as possible. |
| But at the same time they wanted to live somewhere peaceful - |
| they'd both grown up in a rural area and disliked urban life. |
| So the first thing they did was to look for a site. |
| And they found a disused stone quarry in a beautiful area. |
| The price was relatively low, |
| and they liked the idea of recycling the land, as it were. |
| As it was, the quarry was an ugly blot on the landscape, |
| and it wasn't productive any longer, either. |
| They consulted various architects |
| and looked at a number of designs before finally deciding on one. |
| As I've said, |
| it was a design for a sort of underground house, |
| and it was built into the earth itself, with two storeys. |
| The north, east and west sides were set in the earth, |
| and only the sloping, south-facing side was exposed to the light. |
| That was made of a double layer of very strong glass. |
| There were also photovoltaic tiles fixed to the top and bottom of this sloping wall. |
| These are tiles that are designed to store energy from the sun. |
| And the walls had a layer of foam around them too, to increase the insulation. |
| Now, what is of interest to us about this project |
| is the features which make the building energy-efficient. |
| Sunlight floods in through the glass wall, |
| and to maximise it, there are lots of mirrors and windows inside the house. |
| That helps to spread the light around. |
| So that's the first thing - light is utilised as fully as possible. |
| In addition, the special tiles on the outside convert energy from the sun |
| and generate some of the house's electricity. |
| In fact, and it's possible that in future the house may even generate an electricity surplus, |
| and that the owners will be able to sell some to the national grid. |
| As well as that, wherever possible, recycled materials have been used. |
| For example, the floors are made of reclaimed wood. |
| And the owners haven't bought a single item of new furniture - |
| they just kept what they already had. |
| And then there's the system for dealing with the waste produced in the house. |
| This is dealt with organically - |
| it's purified by being filtered through reed beds |
| which have been planted for that purpose in the garden. |
| So the occupants of the house won't pollute the land or use any damaging chemicals. |
| It's true that the actual construction of the house was harmful to the environment, |
| mainly because they had to use massive amounts of concrete - |
| one of the biggest sources of carbon dioxide in manufacturing. |
| And, as you know, this is very damaging to the environment. |
| In total, the house construction has released 70 tons of carbon dioxide into the air. |
| Now that's a frightening thought. |
| However, once the initial 'debt' has been cleared - |
| and it's been calculated that this will only take fifteen years - |
| this underground house won't cost anything - environmentally I mean - |
| because unlike ordinary houses, |
| it is run in a way that is completely environmentally friendly. |
| So, eco-housing like this is likely to become... |