Passivhaus

[DexterH]

Hello all,

First post here!

Passivhaus is an area which seems to be growing more and more as time goes on, and I read recently that Chris Huhne was talking about it being introduced as a mandatory standard for all new builds.

I was just looking to start a discussion on it, what your experiences had been like, and whether you thought introducing it on a wide scale was viable?

We've just started a Passivhaus specific blog, and it would be great to have some feedback on it. You can see it here: http://encraftpassivhaus.wordpress.com/

Thanks!

[martin]

Can you give me one good reason not to nuke this piece of blatant spam by a company that has the idiocy/temerity to feature roof-mounted chocolate teapots on their website?
I'm also somewhat sceptical about the claims of passivhaus' being made "compulsory"

I quote "Some companies are now racing to offer roof-mountable turbines, that can be fitted directly to properties. Encraft can tell you the potential benefits of these turbines in your postcode area by doing the necessary calculations for you.
The main issues in choosing wind power relate to planning permission, which can become onerous if your tower height exceeds 7m"

Utter misleading cobblers! - the damn things are a blatant con, and you should know it!

[DexterH]

Hi Martin,

I certainly didn’t mean to provoke such a reaction. This isn’t spam.

My source for the Chris Huhne speech is here:

http://www.cuttingthecarbon.co.uk/index.php?mact=News,cntnt01,print,0&cntnt01articleid=18&cntnt01showtemplate=false&cntnt01returnid=101

It was during his 2010 speech to the Passivhaus UK Conference.

In terms of the con of roof-mounted wind turbines in built-up and domestic areas– something I would wholly agree with you on - this is something that we have helped to prove.

The Warwick Wind Trials, of which I am sure you are aware, are an internationally renowned trial set up to prove that such wind turbines do not work; the aim of the trial was to rid the market of cowboy installers, and it was a great success. The results can be seen here:

http://www.warwickwindtrials.org.uk/

We initiated and led the project along with Pilkington Energy Efficiency Trust, Warwick District Council, BRE Trust and participating homeowners. It was supported by DTI, BWEA, Warwickshire County Council, Action 21 and the Micropower Council.

I hasten to add that we are not installers, we’re an independent consultancy, and have recently been involved in a project in central Birmingham in which we strongly advised against the installation of a turbine.

Finally, as for the passage you quoted from our website, that only supports you’re argument doesn’t it:

Some companies are now racing to offer roof-mountable turbines, that can be fitted directly to properties. Encraft can tell you the potential benefits of these turbines in your postcode area by doing the necessary calculations for you.

What this implies is that some rogue companies are keen to offer these domestic turbines, hailing them as a great success, but Encraft can offer an impartial assessment to ascertain whether or not it is viable. I.e. we are able to offer incontrovertible evidence that they will not work, if you require us too. We advise against them in any case, without charge.

Sorry to have caused offence, but I hope I have clarified some of the issues. Feel free to ask anymore questions.

[martin]

In my humble opinion there was far too much foot dragging about the chocolate teapot fiasco, and the whole con staggered on for far too long  - they were exposed as a scam on this forum way before the Warwick Wind Trials - leading (genuine) experts pointed out that they were nothing more than a marketing scam as soon as they appeared, but sadly too many had the wool pulled over their eyes by clever marketing.

It may be a touch semantically pedantic, but I take the written word literally - "Encraft can tell you the potential benefits of these turbines in your postcode area by doing the necessary calculations for you" rather says to me that there are "benefits" to be had from the bally things, when we all know there aren't any!

As for "spam", I shall confer with the moderating team...

[clockmanFR]

Terrible blog.
No real info. Just photos of standard normal stuff. normal dropped ceilings for 500mm insulation but where are the roof/wall ties, whats in the cavity. If you are showing pics then explain.

Here's one of my jobs, 500mm wall. Re-used hand made bricks, 100mm cavity that's properly insulated, 150mm thermal block (siporex). Triple glazed Window sits inside and up to the brickwork.

Come on DexterH, if you show pics then give relevant info, or else you sound and look like another company that when the building trade gets tough you jump onto another bandwagon.  

[rondurrans]

Is this a step too far......are there any calcs. showing EE payback of this standard - also the MVHR system energy use, is it quite excessive when you reach such levels of air tightness? 

[martin]

I think we should be looking at such things as Passivhaus techniques, and discussing the relative merits of all sorts of ways of reducing our need for energy - that's what this forum is for - I think that down the years it has an impressive record on the broadness and depth of matters covered, and I hope it will continue doing so.
As to whether another "blog" will contribute anything more to the debate, I sincerely doubt, especially when it brazenly uses a company name in it's title (even though they may claim to be a "consultancy") - as I said, the moderating team will confer over this....

As for boasting of sponsorship from the BWEA and the Micropower Council, both of which did their best to help sell the teapot scam into a gullible market......... it doesn't to my mind reek of lack of commercial bias, impartiality and most important of all - good judgement!......

[Ted]

Would you not expect a politician, when addressing a Passivhaus conference, to do anything other than tell them what they want to hear. No surprises there.

Passivhaus may, or may not, be on the horizon for UK new build specs. But if it is, it is still a very long way away.

There is a recognised road-map for where we are going and we (in Wales) are currently at Code for Sustainable Homes level 3. Level 4 by 2013.

So at that rate we might get to Passivhaus (forget all the Zero Carbon smoke-screen) around 2020.

Anyone building a new home for themselves now would use Passivhaus if they had as much money as sense. Who wouldn't want to reduce their energy demand, and bills, by 90%?  But developers and builders will pretty much only do what they are forced to do.

And you can read my blog here: http://www.caerdelyn.co.uk/blogg/

[rondurrans]

According to Dr Strong the additional cost is 7% (see 2.28 mins into video also take into account the location) http://vimeo.com/9668095

I still think the amount of energy used to achieve such standards is questionable - must be a study somewhere showing the payback of energy - sometimes I feel we are making artificial environments to live in, that is relying upon Mechanical Ventilation even with Heat Recovery still does not 'feel' right - some would argue it is bad enough being in an office all day with a fully automated environment and then going home to one - we lose touch with our external environment. 

[Eleanor]

Ron, I'm more than happy to be in touch with my external environment - when I'm outside! Maybe we all need to get out more .. 

[biff]

ron has a very good point.
                  too much controlled enviroment is not good for us long term, the body need the extremes of temp to make it work properly. the brain get dozy if the conditions are too comfortable,a few degrees lower and there is a definate lift in brain activity,.
   i have no degree in science or such so i could be talking through my hat but going by experience i found that too much heat or dead air makes one dull and fresh air is a must.
                                                biff

[Eleanor]

It’s strange looking back at one’s old quotes, from here http://www.navitron.org.uk/forum/index.php/topic,2795.msg24590.html#msg24590 I clearly wasn’t convinced. Lightfoot was very patient and explained that it is possible to open a window  

Lightfoot et al

I'm not sure that I fancy the idea of a complicated heat recovery system. It does seem that the way we are going houses will be sealed so tightly that the occupants will be suffocated in their beds if the systems fail  . The thought of not being able to open a window without the system going into some sort of demented over compensating frenzy is a bit worrying. But I suppose there will be a control for that too ... a big flashing light and loud voice screaming "window open, window open"    

The PassivHaus is designed around 20C which is far too warm for me - last winter in my leaky caravan it was sometimes < 0C which is slightly too cold  .
In a couple of years I'd like to think we'll be living in a house that can make double figures most of the time without much heating which would be fine  . Natural ventilation would be better but tonight there wouldn’t be any and for the last few weeks it would have been draughty. I do have some misgivings about trying to build to the PH standard, the main one being that I think it’s difficult to achieve without a concrete slab. Most of the rest of it is insulation, orientation, expensive windows and attention to detail  

[camillitech]

I just can't come to terms with MVHR, and believe me I've tried. The very thought of anything running 24/7 no matter how much power they say it uses and returns two or three fold fills me with dread. Perhaps I'm a Luddite or perhaps it's because I'm off grid but I don't care how reliable it is, if it moves it WILL wear out, require servicing, filters changing and make a noise.

We are going to build on a concrete slab, it will have very expensive windows, super insulation and only one door but when the air needs changing I'll open a window and let some of the real stuff in. If we have to use more energy to heat the house that's fine by me, I'll just make more 

Cheers, Paul

[Contadino]

There was a documentary doing the rounds about 2 years ago about Earthships.  The claim the programme makers made was that you could achieve Passivhaus standards without the MVHR machine by having the atrium filled with plants.  The way the earthships are constructed, with each room hanging off the atrium meant that the plants maintain a natural level of humidity throughout the house, and clean the stale air.  It's a nice idea, and I'd like to think that the claim was true, but documentary programme makers tend to make unfounded and bold claims (anyone remember that Farm For The Future PoS? )

Sadly, I can't remember the name of the film, and a bit of googling didn't yield anything.

Every house I've been in that has had a MVHR system in place has either had all the windows open, or has been an unpleasant experience, plus I share Paul's concern about having a mechanical single point of failure.

[camillitech]

I can see the attraction in a town, city or by a motorway but out in the country and especially 'off grid' I'm not convinced. I do like the plant idea though 

Cheers, Paul