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Whatever You Have Learned,

Put It Into Practice

The Code for Sustainable Homes (CfSH) incentivised a high environmental performance across a multitude of different environmental issues.  Energy was the most heavily weight section while other sections included water efficiency,

waste, pollution, management on site, health and well being.


As of March 27, 2015 the Code for Sustainable Homes was officially scrapped by the government as part of its ‘bonfire of red tape’ in the housebuilding sector.  The changes are the culmination of the Housing Standards Review, which aims to reduce the cost and complexity of building homes in England and stop the ‘pick and mix’ approach to housing standards by different local authorities in England.


The government arguably claims it has cut housebuilding regulation by 90%.  The Code for Sustainable Homes allowed councils to adopt their own sustainability levels as a planning requirement for new residential development, with code level 3, 4, 5 or 6 as potential planning conditions.

Elements of the code will now be incorporated into building regulations, which will be re-titled as “the new national technical standards” and set at the equivalent of a code level 4. BRE (formerly the Building Research Establishment) has said it will continue to certify schemes under the code… while setting up a voluntary code called the Home Quality Mark, which is basically an extension/modification of the Code for Sustainable Homes.  Some Councils still request an independent audit of a building’s performance but they can’t demand this, while clients have realised the benefit of providing an independent audit as it smooths the process with the Council, gives reassurance to all and can be used as a significant marketing tool.

We’ve all heard about Energy Performance Certificates (EPC’s) but unless one is an accredited domestic energy assessor that can create an EPC most people generally do not know what this is all based upon…  Simply stated, in 2003 the EU passed a directive on the Energy Performance of Buildings to create a common framework to promote the improvement of energy performance of buildings across the EU.

An EPC should be produced whenever a building is constructed, sold, or rented, and for new-build a Predicted Energy Assessment (PEA) is now normally required for Planning, and should be produced with a planning application as a matter of course.  (Instead of looking at this as another hurdle, when building to a high standard this should be viewed as a great marketing opportunity because the applicant is showing through third-party independent and approved certification the benefits to the community of building a design to high energy efficiency and great environmental impact ratings.)

Thir13en provides the solutions for a sustainable, energy efficient, lo-carbon thermal load-bearing shell for structures wishing to meet higher code applications, while easily meeting and improving upon current legislation. Thir13en has developed relationships to integrate solutions to meet the highest environmental criteria, while keeping the solutions cost effective and user/project friendly, leading to great benefits.

Along with this comes a requirement to focus on CO2 emissions as designers, developers and [in our strict opinion] contractors need to consider the impact that their decisions have on the environment, which is regulated by varied regulations, but we focus mostly on the Building Regulations Part L1A: Conservation of Fuel and Power which requires that SAP calculations are carried out on all new build developments.

SAP – refers to the Government’s ‘Standard Assessment Procedure’ for assessing the energy performance of dwellings.  The SAP rating is based on the energy costs associated with space heating, water heating, ventilation and lighting, less cost savings from energy generation technologies.  It is adjusted for floor area so that it is essentially independent of dwelling size for a given built form.  The SAP rating is expressed on a scale of 1 to 100 – the higher the number, the lower the running costs.


Therefore the following are essential to get the best performance out of a building’s design:

Minimal Thermal Bridging (¥ value)

Excellent Air Tightness

Very Low U-Values

Excellent Heat Loss Parameters

Low Heating Demand


Excellent Ene 1 & 2 performance

Mat 1 -Green Guide System Components A+


Mat 2 – Dependent upon EMS certification


Was 2 – Utilising systems that will help minimise construction waste and divert waste from landfill


Hea 2 – Sound Insulation


Man 2 – Reduction in transport movements to site


…just to mention a few of the most obvious requirements to reap the highest rewards…


CfSH Assessment is a two stage process – design and post construction stage and is carried out by licensed Code assessors.  Assessors submit their reports to the Code Service Provider and after quality assurance checks have been made certificates are issued by the Code Service Provider.


In the Design Stage review, all specifications are assessed wherein a rating is determined, and subject to quality assurance a Design Stage or Interim Certificate (PEA) is awarded prior to the start of construction.


In the Post Construction Stage, the independent assessment confirms that dwellings have either been built to the Design Stage specifications or to documented variations from the Design Stage constituting the ‘As-Built Stage’ which may require testing that confirms performance levels, leading to a Compliance Submission Report to Building Control, culminating in the final EPC and EIR being issued.


The final certificate sets out the dwellings’ SAP and Energy Efficiency ratings which should include a list of recommended upgrades in order of cost effectiveness and this forms part of the HIP (Home Information Pack).


This is where costly and time-consuming situations can become problematic, leading to cost overruns and contract disputes.  No matter how efficient and expert an Architect or Designer may be in designing to higher aspirations such as the higher Codes for Sustainable Homes, many contractors will vary a designer’s design solutions or material specifications simply because they do not realise the importance of following direct specifications to achieve the end result required.


We’ve seen this way too many times, even when an Architectural Technologist is involved, as a Contractor substitutes a product for whatever reason and this can ultimately have a serious impact on the energy efficiency of the structure, or the environmental rating, [because of how Ratings are configured] thereby seriously impacting on the final Energy Performance and Environmental Impact Certificates… This can lead to a Council’s Building Control to state that the Applicant has not met the promise against which Planning was approved, leading to possibly very costly reparations and time delays which ultimately the Client pays for in one manner or another.


The Code for Sustainable Homes or the new National Technical Standards is nothing to be afraid of, or disparage, as it has been created to pull the housing development sector together to meet Governmental Requirements, while at the same time creating a template for oversight, keeping honest people honest.


All it takes is an understanding of how material and climate dynamics work together to create an easily controlled micro-climate. From experience, we’ve found that it does not cost more to build better… just better planning and execution, from the outset!


Portions of The Codes for Sustainable Homes is slowly being integrated into Building Regulations and may be done away with at the end of the day, just as portions of the PassivHaus Standard is being assimilated, and we can advise from personal experiences when one should follow one path or the other, or potentially choose a third path.  Thir13en works with a client to ensure avoidance of the pitfalls that many fall into, preferably from the outset at an early design stage so works do not need to be duplicated, ensuring a smooth solution path to implement the results desired, to the benefit of all.  Everybody likes a successful project, and client satisfaction is the sweetest reward of all.

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