I have been looking through posts on this site regarding CfSH and thought I would share my experience and some advice which hopefully people will find useful.

I am an architect and in the process of building my own house. I am a big fan of the CfSH in principle as it takes such a broad outlook on a property / project, something which all other standards seem to fail in. When looking at finding an assessor I was a bit taken aback by the price quotes, and consequently undertook the training myself to become an assessor as it would also be another string to my bow for my architectural practice http://www.pa-ad.co.uk/.

Through the training and my experience thus far it has become blatantly obvious that CfSH is great in principal but not in practice. I myself am going for level 6 on my project (http://the-old-lemonade-factory.blogspot.com/) but the extra cost involved is quite shocking, hence the reason it will never become mainstream. There are benefits involved such as reduced mortgage rates and exemption from stamp duty, as well as the personal satisfaction, a practical efficient and green home, but these do not help with the upfront costs involved.

I would say that levels 3 & 4 are reasonably easy to achieve, especially if you are going for some sort of ecohome, but 5 & 6 are hard to achieve and will come at considerable financial cost. An essential piece of advice would be to get someone involved who are competent with and have a good knowledge of CfSH at concept / planning stage. Leaving the assessment to the end could leave you with lots of stressful and financial headaches. It will also save you money, as you will be able to pre determine where you can score the amount of points you require and how do this economically - to revisit this afterwards can be very costly and extend the project time considerably.

I would also suggest that serious thought be given to why you want a CfSH rating as it is costly and with the higher levels quite restricting on how you design and build your home. I would even go as far as saying that unless a site is suited towards the CfSH criteria, it may be very hard to achieve a level 5 and impossible to get a level 6.

I hope people will find this info of some use.

Nigel

I wholeheartedly agree about CfSH. Having designed my new house to be as close to passivhaus standards as possible, using a high percentage of renewable materials, solar PV and solar thermal, rainwater harvesting and no fossil fuel use (other than that needed to generate electricity) I was surprised to see that I'm going to struggle to get level 5.

The truly daft thing is that I may well end up with a house that is, in reality, zero carbon and with very low embodied energy and water usage, yet only rates level 4, because other elements cannot achieve a high enough rating under the assessment procedure..

I am not totally clear upon where it is required, but as I understand it, it only compulsory on new builds in Wales I think currently level 3 going to level 4 in the near future. Social housing with funding from government bodies / agencies require it. Also sometimes it is a condition in planning although I have not personally heard of a case. Think if a planning permission is controversial then the applicant committing to CfSH can help their case.

Financial benefits are from reduced mortgage rates (this is one but there are others http://www.ecology.co.uk/html/mortgages/discounts.htm), exemption from stamp duty (which could be a big saving) and the property will be an extremely efficient one. I don't think that it would add anything to the resale value of your house unless you are going for level 6 (zero carbon) which may appeal greatly to some people. It also acts as a good practice design tool but this has no consequence on actually getting assessed.

Thanks for the positive feedback on the blog. I have started the story of our project and will add installments each day over the coming weeks. I will also be adding news and images as and when. I have also done twitter @buildzerocarbon and facebook www.­facebook.­com/­pages/­The-­Old-­Lemonade-­Factory/­231090636959395 Will also be trying to get in press etc.

Nigel...

It was mandatory for all new dwellings to have a code rating (even if it was a nil rating); However the Government announced the suspension of Home Information Packs (HIPs) from 21 May 2010 and the requirement for sellers to give a sustainability certificate (either a Code for Sustainable Homes certificate or a nil-rated certificate) to buyers of newly constructed homes was also suspended.

A Code rating now is as mentioned generally a requirement for Social Housing developments or occasionally a planning condition from Local Planning Authorities for development of a given site.

Part of the problem for the specific example above is use of a heat pump as the heating/hot water system. By setting the main fuel type as electric, the Target Emission Rate is set much higher, albeit the DER will typically be well below this - commonly referred to as the 'Code 4 loophole'. However The actual DER is still quite a high number compared to say gas or a wood burner for main fuel. The Code 5 target is for a DER of zero, so the higher the start number - the more you need to do to get down to zero.

Code 6 is for DER of zero + cooking and appliances also compensated for (which aren't considered in SAP).

The only way to get to Code 6 is for lots of electricity generation - PV or wind typically - and lots of it.

There is also a requirement for a low Fabric Energy Efficiency target (ENE 2) - This bit is much easier to achieve(comparatively).

Whatever the wikipedia entry on CfSH might say, Codes 1 to 6 are all still doable I believe, but the ENE1 bit is set as mandatory minimum of L1A 2010 compliance, which equates to around the same level of Code 3 from previous version of the code. In practice though, most people look to achieve Code 3 or better if they do aim for a Code rating (Social Housing more commonly Code 4).

The code covers a lot more than just the energy and CO2 emissions requirements.

The reality is that there is enough PV and solar thermal to meet the house energy needs, I believe, but the fact that the heating and DHW is electrically powered is the killer.

I were to fit a dirty, high emission, wood burner, sacrifice all that airtightness for the sake of having a flue and all that entails and use a non-sustainable (in this part of the UK) fuel like wood I could get a higher Code for Sustainable Homes rating?

Barking mad or what..................

C4SH is obligatory for all new-build in Wales; private domestic Level3 minimum.

As someone said earlier in the post, if you get a 'switched-on' C4SH Assessor in at the beginning, it is not much effort at all, just a bit beyond Building Regs for L3 and L4.

However, as a post-build exercise, almost impossible, and very expensive, retro-fits cost way more than if they were planned for!

Some people don't appreciate that the C4SH also covers the building process as well as the building itself, and is designed to improve the whole construction process. Whether this is sensible or not is open to debate.....?

Also, our biggest problem as C4SH Consultants is explaining to small developers/builders, that it is designed for biggish developments, 40 dwellings plus, and does not sit well with a single dwelling construction. There (in my opinion) should be let-outs or exemptions/defaults for self-build single dwellings.....

Cheers...

JSH,

Yes, as you probably realise, you cannot get C4SH L6 with the 'dwelling' alone, you need the other bits around, the Considerate Constructors Scheme, Home User Guides, Ecology Reports etc etc... These are over and extra to a single dwelling, just not worth it.... the C4SH hs been badly implemented in my opinion, but then if you look at who has been 'driving' it, perhaps not that much of a surprise....

Cheers...

Glazing area will be modest and all passivhaus certified. Building is very airtight by design. MVHR and the ASHP together recover around 85 to 90% of the waste ventilation heat. Cold bridging has been designed out and house will be on a well insulated slab with detailed attention paid to the wall/slab joint. Assessment has been done using Stroma FSAP 2009. In all probability the house could be passivhaus certified if I wanted the hassle and cost of doing it.

I am also using FSAP so may be able to help out. You say you have designed out cold bridging - is this reflected in the y-value you have entered (opaque elements tab at top) / what value is it?, also what FEE value are you getting?

<blockquote><cite>Posted By: Nigejk</cite>JS Harris for the code assessment bizarrely gas seems to be the way forward. I have been round the houses with my heating systems. I have finally decided on solar thermal with gas boiler backup. Although a gas boiler does bump up the CO2 created it will get you the points for the NOx emmissions POL2. I have even tried the averaging of NOx emmissions but to no avail (and to be blunt the averaging calculation is so far off the mark it is unreal). The POL2 will get you more than 2 points out of the possible 100, so worth it in my opinion.

I think it is a prime case of where the code is flawed it is pushing you down an avenue that you have to do a particular thing to get points when I believe it is not necassarily the best or greenest solution. I have put so much time and money into getting level 6 I am not going to sacrifice changing to a different heating system. This is also a good example of when knowledge of the code is invaluable at design stage. I spent a long time to come to the conclusions of what is best.</blockquote>

That is a superb example of the flaws in the code! Pushing you to use gas just to get extra points for NOx seems bizarre. If it properly allowed for the offset from PV then perhaps an all-electric house might score more highly, but as far as I can see it doesn't. One issue is that the DHW calculation in SAP is a bit generic and doesn't match well to our needs I've found. I know our DHW requirement and it's about 1/2 of that predicted by SAP (maybe we're just frugal......). This skews the result, too, as DHW is the most significant energy consumer in the house through the year.

Andy,

I sympathise with your problems.... the C4SH is not well suited for self-build or single plots; it has been designed primarily to influence larger spec-built and main-stream developments. I am not an apologist for the C4SH in any way, but without it, no one is going to drive upwards the standards in domestic dwellings in the UK? Nearly every developer we have met or worked with in the last few years only is concerned with maximising profit at the expense of the people who end up living in their dwellings. They all winge about increased levels of insulation eating into their profit margin....

However, once we have explained the aims of the C4SH to builders/owners involved in self-build, for Level 3 it is not much more than Building Regs., and little beyond.

Perhaps your bad experiences are due to lack of information at the outset, and your Assessor(s) not being fully conversant with SAP and Building Regs?
I have seen some C4SH pre-Assessments that are rubbish, they bear no relation to the proposed dwelling, and if left intact would lead the owners into a minefield, of retro-fitting and expensive 3rd party reports, that cost money for no benefit other than a paper Certificate!

I am not trying to blow our own 'corporate' trumpet, but we try to show our clients the most cost effective way to whichever Level they wish to acheive, and so far it seems to be working.

Cheers...

Posted By: Joiner"Corporate trumpet."

Isn't that what BT used when they were making those excessive profits in the 90's

Fred,

(Tongue_in_cheek_mode) You're not a developer, are you...? (Tongue_in_cheek_mode off)

Posted By: Fred56The code is a very expensive road block to building. The only people who seem to like are the assessors and consultants raking in their fees for pointless work and dragging out the time taken.

It may be a troll but .... If we do not have something of this ilk, how do we push up the appalling build standards we currently tolerate? The house I currently rent is less than 10 years old and the build quality is just awful. I don't think it is the best way forward; a concerted push on quality of build, air tightness, and insulation levels alone would make a huge impact. SAP is a joke; but it is a start.

Wasn't part of the reason the changes to the planning system were being proposed, to make it easier for self-builders? Sure I read that somewhere.