My Theory, Facts & Figures

I would say that my theory is based on common sense rather hard scientific facts but nevertheless I have found that common sense often prevails.

The first thing I learnt was that there is a whole industry out there, grown up on the back of what I call 'Greenwash'. By this I mean, selling you energy saving kit you probably do not need and certainly will not save you money. The majority of people do not need expensive heat pumps, solar PV, solar thermal etc if you can get mains services i.e gas, electric.

From this I developed the 'Fab Roi' principle. This is based on a Fabric First build i.e. put all your efforts into building a super insulated airtight house, taking care not to over engineer it, otherwise costs can spiral.

Then every bit of 'kit' I considered for the house was assessed on its Return On Investment (ROI) performance based on the following:- 1-5 years, almost certainly goes in, 6-10 years and it is carefully considered, over 10 years then it was thrown out.  My reasoning on this is that technology is moving at a pace that within 5 years most of what is today considered efficient is likely to be surpassed

Our house is close to Passive House Standards but there are three main reasons I did not go the 'whole hog'. There is a significant cost in achieving the last 5-10% of the passive house standard but can cost 30% plus of the total build cost - so therefore did not pass my ROI test. The second reason is that not everyone has a house that sits on a nice sunny south facing plot. The third is design, I am passionate about getting houses to look good and fit in with their surroundings. Passive Houses tend to look modern unless you again spend a fortune.

So with my basic theories out of the way. What did we build?

So we knew we wanted a sort of Victorian/Georgian style property but one that firmly had its roots in Sussex. We are lucky to be building in a country setting, so decided that a New England weatherboard house would be ideal, particularly as this 'American' style actually originated in Kent & Sussex.  For the interior, rather than slavishly follow one style, we picked all the bits we liked from Victorian, Georgian, Colonial, Baroque and as my wife, Liz, designed it, a new style was born - 'Queen Liz' style. I feared at one point that mixing up the styles could end in a mess but I think she has done a stunning job and hope you agree.

Some other tips for interior design. When designing the interior space many self builders fall into the trap of making rooms too big. Avoid this, as you end up just building a big house not a warm inviting home.  Get the flow right to suit your living style and mix up the roof heights.  If there is one thing that can make a room boring it is the standard 2.4m ceiling height.

Now for the technical stuff........

Timber frame house using rockwool/HD EPS in the walls and roof with an insulated beam and block floor. So the house is like a big thermos flask wrapped in insulation. U values for walls/roof/ floor approx 0.12 Great attention paid to airtightness. The goal was 0.6 but we always knew this would be impossible as we have 3g sash because we chose design over performance, but we managed to get airtightness down to 1. Installed a MVHR system - brilliant by the way, the house is so fresh - and for heating a simple gas condensing boiler feeding U/F heating to groundfloor. The house is SW facing and we do have significant solar gain. Things we did consider, solar thermal, heat sink under the house, water recycling but none came close to passing the ROI test.