I have my first self build in for planning approval at the moment - a 250 sq m New England style timber framed house - with no particular requirements of the local authority to achieve any CSH level

My issue is whether to go for a normal gas boiler and some reasonable level of insulation to do the minimum to get through Building Regulations or to try and ramp things up a bit to achieve a higher energy efficiency

I've looked at MVHR (including linked in air source heat pumps), passive stack ventilation, passive flue gas heat recovery, heat pumps, CHP, pv, solar water, the NHBC report (Energy efficient fixed appliance and building control systems) etc (wind, biomass, water not relevant to us) - but it all seems so expensive for the payback that you get out of it. And that's not including electricity costs, breakdowns, maintenance, ancillaries (filters etc), reduced house value (arguable maybe)

Everything seems to be based on 10 year returns which when you take in product obsolescence and ancillary costs seems way too long. Are equipment prices being somehow based (managed) on this assumption? For example if income from the government went up and/or electricity prices increased would the capital cost of all the energy equipment also go up to maintain the ten year formula? Or maybe I'm being too cynical. Would there be so many self build magazines around without the advertising revenues of all the energy saving suppliers? (and what impact does this have on their editorial policies?)

And does the UK really warrant these costs in any event? (we are not Scandinavia or Germany with consistently lower temperatures through the winter)

I just wonder if, to some extent, the self build community just chasing the law of diminishing returns with all of this?

Are there proven technologies with fast pay backs (under 5 years) that a novice like myself should be looking at
- or is it just the case of closing the trickle vents in winter and remembering to switch the lights out!

Sorry for the element of frustration

Yes, insulation and associated airtightness every time. You don't see insulation either, or hear it, smell it. It is the unsung hero.

DHW is my biggest energy use and in my location solar thermal is probably with while, but I would go looking for the cheapest system I could find rather than the most efficient, because, as you say it is a law of diminishing returns.

Seret has a formula that seem quite sensible:

£ kgCO2e-1 per year

Or if I understand it correctly, how much CO2 do I save every year for every improvement £ I spend. This takes into account different fuel types and overall conversion efficiencies.

Have to look at the whole story. A 10 year pay back on something that's going to last 50 is better than a 6 year payback on something that will last only 7 years.

A bit of a mantra on is fundamentals and I am a strong believer in KISS. The 3 best things you can do are a bit like a Tony Blair speech - education education education, but substitute educ with insul. After that airtightness.

When planning our build 4 years ago, I wanted all the gizmos, but they were the first things to cut to keep on top of the budget.

Mags are full of ads and features but it is the only way they can make money, but does not reflect what the majority actually do.

You learn far more from here than you ever will from a mag, I now I have.

Good luck,

Nik

Posted By: SteamyTeaNot of you move in 5 years

I'm hoping the day will come when a higher EPC rating and demonstrably lower bills will be worth something when you come to sell.

Our big local estate agents are now showing the EPC headline figures on their newspaper advertising. i.e. mention EPC in a 50x50mm Ad (which is mostly photo).

This seems like a game changer as previously they were at the back of a 4 A4 page brochure, if at all (once you'd already decided you liked a house).

To return to the original question, yes, insulate, insulate, insulate.

I have a newly built t/f house; been in it 18 months. I looked at all the technology and decided not to put any of it in. The only thing we did include, and I will never see payback, is a 6000 litre rain water collection tank. It's good to know that flushing the toilet is free, if one discounts the initial installation cost!

Warmcell insulation and 3g are brilliant. I have 300mm in the roof and am the only house in the street that still has a good layer of snow. A newly built neighbouring house, brick built by a 'luxury house building company' has all of 100mm Celotex in the roof and all the snow had melted three days ago.

So save on technology, spend the money on increasing the insulation thickness and being super, super super diligent on air tightness. Then add MVHR. The two matra that I was advised to follow; Insulate, Insulate, Insulate and Build Tight, Ventilate Right!

Rex