Trafford Eco House

Our latest planning application is in – we’ve made many, many, changes to placate the council but have managed to keep the main elements that improve the house’s performance:

  • 200mm of external insulation
  • Extensive solar PV
  • Locally-made triple-glazed windows
  • A large thermal store, heated by solar thermal and a woodburner

Overall we’re still targeting a reduction in heating requirement of up to 95%, and to be a net producer of energy. All of this can only get built though if we can get planning approval though, and to date that has been difficult.

We need your help

We need to show that there is support for this type of sustainable building. We’re getting our neighbours to write letters of support, and add supporting comments to the planning application online – but the more we can get, the better.

What you can do – by November 27

Have a look at the planning documents, our application number is 81791/HHA/2013  and the documents can be seen here

If you have any questions, please contact us and I’ll do my best to get back to you quickly. If you’re happy then please send in a supportive comment. You can do that in three ways:

Online

The quickest way is to add your comment using the council’s online form with our application number – 81791/HHA/2013

Send an email

Or you can send your response to planning@trafford.gov.uk. Please be sure to include the planning application number (81791/HHA/2013), your name and address and your comments.

Snail mail

You can write to the Chief Planning Officer, but please be quick – we need all comments in by the 27th of November:
Planning and Building Control, PO Box 96, Waterside House, Sale Waterside, Tatton Road, Sale M33 7ZF

 

Please do what you can – we only have until November 27 to get comments in!

I’ve just realised that I haven’t made enough of some of the great people I’ve met who are also undergoing this amazing green journey – downshifting or re-moulding their lives to their views of the new reality we face. There are so many of them I won’t attempt to get them all into one post, so here is a teaser for you . . .

Becoming Domestic

Living the dream – a rollercoaster ride into the realities of downshifting with a family. Inspirational and nailbiting, as well as practical and down to earth . . well worth a read – becomingdomestic.co.uk

The ultimate pantry

Green Cottage

From someone who faces the workday reality of trying to tackle climate change through the constraints of local government – and at the end of the day he walks the walk – combining low-cost renovation of a Victorian terrace with high-effort regeneration of a woodland – ourgreencottage.wordpress.com

Away from green cottage – valley wood

La Ferme de Sourrou

La Ferme de Sourrou is where I see myself in another life – without the daily schoolrun or the pressures of catchments and SATs. Amazing tales of self-building and self-sufficiency, wonderful gardens and animals – read more at lafermedesourrou.blogspot.co.uk – and have a look at the gorgeous photos.

It’s all about the chickens

It’s been a great 2010 at the Trafford Eco-House, we’ve not posted updates recently not due to lack of activity, but the opposite!

The garden’s been going well and we’ve got trout and beds of winter veg surviving the snow. The pace isn’t going to stop in 2011 though, this is the year when the changes to the house should happen: Solar PV, Solar Thermal, Woodburner with Flue Boiler, extension with bike garage, wrap the whole thing in external insulation, put up much thicker curtains.

The garden in 2011 will keep us busy too – we’ll fix up the shed and give it a green roof, expand the aquaponics, and dig over another 500sqft of turf into veg patch.

Looks like a fantastic year ahead, and we’re really looking forward to what we’ll be saying this time next year.

Hope you’ve all had a good 2010, and are looking forward to an even better 2011.

We’re looking at windows at the moment, and trying to work out what will fit into our budget while giving us the best possible insulation effect (U-Value). The PassivHaus standards state that our windows should have a U value of <= 0.8 W/m2K, so we’re going to try and get as close to that as possible.

It has been suggested that, rather than going for PassivHaus certified triple-glazed units we should go for double glazing and put up some insulated curtains. I’m not sure that would work for every window we have, but it could deliver real cost  savings if it can deliver a decent U-Value.

Not surprisingly, very few people are prepared to put a U-Value on curtains! But I found this great table over at Action 21. It compares the different U-Values for windows alone, and then the total U-Value if using heavy curtains or insulated  shutters.

Window U-value [W/m2K]
Window only
(daytime / nighttime)
with heavy curtains
(nighttime)
with insulated shutters (nighttime)
Single glazed 4.5 3.3-3.6 2.6-3.1
Double glazed, 12mm cavity 2.8 1.9-2.3 1.3-1.7
Double glazed, 16mm cavity, low-E 2.0 1.2-1.6 0.7-1.1
Triple glazed 2.5 1.7-2.1 1.0-1.4
Triple glazed, 2 low-E, Argon filled 1.7 0.8-1.3 0.4-0.8

So it looks like we could get down to 1.2-1.6  with curtains – it’s not 0.8, but it’s pretty close, and according to this table is lower than standard triple glazing.

So this is well worth consideration – but what type of curtains would we need to get those results? Here’s what the Yellow House have to say:

Ecodesign books sometimes talk of “insulating curtains”. These would have to be home-made curtains of insulation sewn between fabric. In order to avoid downdraughts from the window they must fit snugly into a pelmet at the top and a tuckslot at the bottom. In theory an insulating curtain with 60mm mineral wool reduces the u-value of a double glazed window by 75% to 0.6. However they very hard to clean, and there are potential health issues with sharing a living space with mineral wool. A better option might be to convert old duvets into curtains, or make insulation shutters from timber and insulation sheeting. Our feeling is that all these options represent a major intrusion into the living space and are not appropriate for a normal house – though they would be justified in a solar house where there are very large areas of glazing.

Duvets at Sainsbury’s are now incredibly cheap – so maybe that’s what we’ll go for – I’ll chase up prices against triple-glazing.

Resources

In my PassivHaus Renovation post I said that:

Any non-solar water heating to be Gas Condensing boiler or CHP – wood fired stoves are not permitted (this conflicts with my peak-oil resilience planning)

In return I got a comment posted by Andy Simmonds at the AECB stating:

The AECB standards do not proscribe wood stoves, nor does the german version of the PassivHaus standard.

I’ve been back to the AECB standards and here are the sections of the Proscriptive Standard that deal with heating & cooking:

Space heating (Silver Standard):

Normally radiators or underfloor pipes. Fed from SEDBUK A-rated mains gas condensing boiler, CHP or, outside the gas supply area, SEDBUK A-rated LPG or oil condensing boiler, earth-source heat pump (seasonal COP ≥3.0) or cleanburning biomass boiler; i.e, one using liquid or gaseous fuels. Wood pellet boilers are permitted outside the gas supply area but are not encouraged due to the exhaust emissions. Blocks of flats or maisonettes to have a central boiler and/or CHP plant or heat mains connection; i.e. heat distribution within the block rather than individual boilers or electric heating.

Space heating (Gold Standard):

Normally hot water coil(s) in ventilation ductwork. Circulating pump consumption ≤0.1 W per m2 floor area or pro rata; e.g., Grundfos Alpha Pro or equiv. Heat sources as for Silver.

Cooking (Gold Standard):

Hobs gas, LPG, electric induction or clean-burning biomass – liquids or gases only. Ovens gas, LPG or electric A-rated. Electric min. A+ or A++

I don’t see anything in there which suggests a wood-burner would be permitted? I’ll have a chat to Andy and see if he can clarify things for me!

The more I get into looking at insulating our house, the more I need to learn! At the moment I’m fighting off a swarm of mismatched R, U, and k values. All I want to know is what type of insulation we need to come close to the PassivHaus standards but everything I see is quoting differing units. So what are all those units? and what’s the relationship between them?

What are R,U and k

  • k is the Thermal Conductivity of a material, so for Insulation LOWER is better. Units are W/mK.
  • R is Thermal Resistance of a specific piece of insulation, we want this to be as high as possible. Units are Km²/W. It is calculated as d/k where d is the thickness of the insulation and k is the Thermal Conductivity.
  • U is the Thermal Conductivity of a specific piece of insulation or building element and, as with k, lower is better.  Its units are W/m²K. It is calculated as 1/R or k/d. 

MySipHouse

MySipHouse

Looks like our dream house may be an as-PassivHaus-as-possible extension of a traditional 3-bed semi. So now I’m looking at how we make that happen. One of the things I’ve come across are Structural Insulated Panels. Essentially these are a thick “sandwich”, with two wooden panels separated by a thick layer of insulating foam. One of their advantages is size – you can get panels up to about 6m long, factory-cut to your dimensions, with all the window and door holes pre-cut. And that means that you can have a very short on-site build time – some SIPs builders claim to be able to have the house built in under a week. It also means you have less joints to compromise your insulation and airtightness.

While they are not all natural – the core is plastic – they do have several real positives:

  • All the  offcuts can be recycled at the factory – no skip required!
  • They use up to 50% less raw timber than a timber-framed house
  • They can result in thinner insulated walls than other methods – 150mm vs 250mm for a cavity wall
  • A typical U Value would be .22 w/m2K – heading for PassivHaus standards

There are lots of considerations when using them though:

  • You need to do all your planning up-front.
  • Use an architect and builder with SIP experience or you’re in for a world of (expensive) pain  caused by last-minute changes.
  • Try to ensure as much of the electrical and plumbing work is done on the internal walls to reduce the impacts on the insulation
  • Ensure that the builders seal all joints correctly with insulating foam (urethane) 
  • You may need to use a vapour barrier to prevent condensation inside panel, which could lead to rot.

They certainly seem to tick a lot of our boxes – they’ll go on the list as a possible option.

Resources