Nick's New House

Design Philosophy

Setting goals

• First and foremost, the house must be affordable as I am unwaged and therefore have a very fixed budget based on the price I will get for my present home.
• Bearing in mind that I am unable to go out to work and that any future employment may involve me working from home, I want to be feel happy and be healthy in the new design. That means plenty of space (as much as my budget will allow) and plenty of light.
• The construction of this dwelling must comply with my strongly held environmental principles.

For a long time I have been interested in timber-framed buildings for the advantages they offer over the brick/block/concrete alternatives. However, while watching the building of several timber-framed houses on television, I couldn't help feeling that the amount of timber being consumed in their construction was rather extravagant. I don't want anything which anybody else couldn't have and if we all wanted to live in timber-framed houses, there wouldn't be a tree left standing on the planet!

Then I came across a design which is referred to as a 'Zero Heat' house. The design goal of the 'Zero Heat' house is to reduce the need for additional heating (it's main source being from solar heat) to as close to zero as possible. The design uses Masonite panels that are made from thin ply and other recycled timber and are extremely economical in their use of timber. The box sections created are just a strong as any brick or block wall and it is possible to achieve very thick walls at little extra cost which can then be filled with large amounts of insulation.

Next, I came across a design for a house on the Fillcrete web site. This seemed to fill all three of the fundemental goals that I had set for my own design so I read all I could about the project. I say project, because this was not just a design 'on paper'. The house had actually been built and lived in. Better still, the performance of the house is being monitored by Aberdeen University as an ongoing project. Having spent a lot of time surfing the net, I haven't yet come across another design that I like better, so I am now looking at refining the 'Zero Heat' design and tailoring it to my own requirements.

You can read more details about the 'Zero Heat' house HERE.

Things I may change

After further research, there are some aspects of the 'Zero Heat' design that I may alter.

• It may be beneficial to increase the amount of thermal mass storage primarily by building the main dividing walls (that run from front to back on the ground floor) of block. Additional mass could be used, eg an indoor pond or water feature.
• Replacing the active heat-exchange system with passive ventillation provided by 'earthtubes'. See HERE for full details.
• Adding a conservatory to the front of the building that will act as a buffer zone between the exterior and the main living area.
• Raising the height of the rear wall in order to increase the amount of useable space on the top floor.
• Not using the Velux roof windows over the upstairs bedrooms to prevent them becoming too hot in summer.

How Green?

Going 'green' isn't a cheap affair unfortunately and as much as I would like to live in a completely autonomous house, I just couldn't afford the initial capital cost! So, it's now a matter of working out what I can afford to do, to both reduce the impact my home will have on the environment, and save me some money.

There are two aspects of 'going green' when building a new home. The first is how 'green' the actual house is in terms of the amount of energy that is required for its construction and how much pollution is generated. The second is how little energy the house (or household) consumes during its lifetime.

As regards the building of the house, here are some of the 'greener' options.

• Construction from wood which is a renewable resourse. Better still, using that wood economically in Masonite panels.
• Keeping the amount of concrete to a minimum. Concrete production results in a lot of pollution.
• Using recycled materials where possible. I am looking at recycled roof slates made from old car tyres. Read more about them HERE.
• Using materials that are easily replaced. Timber from managed resourses is an example.
• Using materials that can be easily and safely disposed of at the end of their 'life'. Again, timber is a good example.
• Using materials that do not have to be transported too far. So stone from a local quarry may be better than timber that comes from the other side of the world.

Once the house is built, the options for reducing its impact on the environment include:

• Passive solar heating (where the air in the house is heated by solar heat from the sun. This heat is also stored in the thermal mass of the building)
• Solar Water heating
• Generation of electricity from photovoltaic panels (PV's) or wind turbine.
• Harvesting of rainwater.
• Treatment of grey water (ie water from shower, sink, washing machine etc)
• Treatment of black water (ie water from toilet)
• Heat from heat pump (where heat is 'pumped from the ground)
• Heat recovery system (where heat from air being pumped out of the house is used to preheat fresh air being pumped in)

Apart from the fact that most of the above cost quite a bit to implement, many of them are not quite as 'green' as they are promoted to be. For instance, a heat recovery system requires electricity to keep it running. So does a heat pump system. Of course, both systems will arguably keep the occupants of a house cosier for less money than more conventional heating systems but they certainly don't provide 'free' heating.

In my own case, my current expenditure on gas and electricity is very low so it will be more difficult for me to save money. What I am aiming to do is keep my expenditure, and use of energy, the same while improving my comfort level.

One particular example that I have been looking into is that of a solar hot water system. On the face of it, this looks to be a very good idea, with a lot of hot water being produced at almost no running costs, at least for much of the year. However, in my case, where I am living on my own, I don't need so much hot water although some of the hot water could be used for space heating. But what about on those days, usually during the winter, when the solar heating doesn't provide hot water? Then it will be necessary to heat the water in the storage tank whereas in my present home, I use an instantaneous water-heater, heating only the water that I actually use. Depending on the number of days that I need to do so, this could result in me using nearly as much gas as I use now! So,I must consider if buying a £1500 solar hot water system is actually going to save a significant amount of energy and save me any money.

So I now have to decide which of the 'green' systems I will have in my new home. At present, and subject to further investigation, I will have:

• Rainwater harvesting.
  Not overly expensive and with water predicted to become very scarce, it's becoming ever more important to use as little as we can.
• Grey water recycling.
  As above.

• Solar hot water.
  After talking with somebody who sells solar water heating systems, I have decided not to include this at the outset. I may consider this later, especially if I share the house with another occupant. Even if I can't use all the hot water for washing and bathing, I may be able to utilise it for heating. However, I am still concerned that my present arrangement for heating only costs a maximum of £40 a year and a £1600 system will have a pay-back time of 40 years even if it produced all my hot water requirements which it won't.
• A geo-thermal heat pump system.
  Cost will be the deciding factor but it's a good idea in principle.
• A heat recovery ventillation system.
  Subject to running costs. Is a passive ventillation system practical and are there any negatives?
• A small wind turbine to generate some electrical power.
  The cost of a Two kilowatt PV system is approxiamtely £12,000. That would produce about 1500 units of electrical power each year, just over half of what I use now. Even with a 50% government grant, it would still take me over 66 years to break even! So my next investigation is to find out if wind power more cost-effective/practical?

A moan

Nearly every system that is available costs so much that you would have to be using very high amounts of energy for them to be economically sensible. But for most domestic dwellings, green/alternative energy is only an attractive economical propostion for the rich!

No doubt that this situation would improve if the products on offer were produced in higher numbers. But the demand will only increase if the prices come down. Obviously what is needed is action from governments to offer realistic subsidies on green energy systems, at least in the beginning to stimulate demand. Any subsidies could be funded by an increase in tax on energy supplies which should be on a sliding basis. For instance, the first so many units that you use would be taxed at the existing rate. Above that the rate of tax increases in steps as the usage increases. That way, the people who causes the most pollution pay the highest price.