New Standards... and How to Achieve Them

A number of local authorities have started to set Level 3 of the Code for Sustainable Homes as the new standard for planning applications. While this may seem like another meaningless layer of local bureaucracy on a par with Design and Access Statements, this does in fact have significant implications for self-builders. Level 3 is a major step up from the Merton Rule and Level 1, which has already been set by some authorities, and moves us closer to the zerocarbon target set by the Government, which in its Building a Greener Future: Towards Zero- Carbon Development document originally outlined these improvements to be introduced in 2010 (with the aim of zero-carbon homes by 2016).

The question that confused self-builders (and their designers) now face is: how best to do it? And like most things there is a hard way and an easier way.

To achieve Code 3, you’ll need to meet four requirements:

• The recent changes to Part L (Conservation of Fuel and Power) of the Building Regulations (a 25% improvement on the 2008 requirements)
• Water use to a maximum of 105 litres per person per day
• Meet minimum requirements for surface water run-off, waste management and materials
• Obtain 46.7 points in “other” items

Let’s look at each one in turn.

A 25% Improvement on Part L?

Hitting the 25% target can be done with insulation alone, but in some circumstances it may be difficult. The SAP calculation will tell you exactly what needs to be done but generally upgrading insulation to the roof, walls and floor is enough. Improving the air-tightness and the U-value of windows and doors has a relatively small impact but can be quite expensive.

Fitting a solar panel can be the easy option. It will give an immediate 10% improvement to the average house, and together with low-energy lighting and Arated appliances, means that only a small improvement to loft insulation will be needed to hit the target.

For a full guide to the new changes to Part L click here.

Reduce Water Use?

Typical UK water use is around 150 litres per person per day. But in this case it is the house that is measured, not the people in it. So a house with four double bedrooms with two people living in it will still be counted as eight potential occupants. Hitting the target of 105 litres per person per day can involve things like low-flow showers, aerated taps, low-flush WCs and no baths.

The easiest, and cheapest, way is to install a rainwater-harvesting system and connect it to the WCs and washing machine. Cost will be £2,000 to £3,500 and will allow decent showers, the odd bath and better taps. After all the hype, it’s finally real (at least for some of us). As more and more planning authorities introduce a standard requirement for new homes to meet Level 3 of the Code for Sustainable Homes, Tim Pullen explains exactly what it means, and how best to meet it.

Meet Minimum Requirements?

The requirement is to hit a minimum standard for surface water run-off, site waste management and using sustainable materials.

Surface water run-off — what falls on the site stays on the site (actually, no more runs off the site than before the house went up). In reality if you have installed the rainwater-harvesting system suggested above, the problem goes away. If not then you need to think about water-permeable hard surfaces like drives and patios and perhaps a rainwater soakaway.

Site waste management can be a problem but an organisation called WRAP (Waste and Resources Action Programme) can help. They will provide a template, free of charge, to help you deliver best practice.

Using sustainable materials is the most difficult of all the requirements — to fail at. The requirement is to achieve at least a D rating from the BRE Green Guide on three of the key elements of the build (walls, roof, floors, windows and doors, etc.). The vast majority of ratings in the guide are A, some A+. It is really only concrete that gives a problem. Traditional cavity walls and timber frame are both Arated. Focus on the roof, external walls and upper floors, and any but extraordinary construction will easily qualify.

What About the Other 46.7 Points?

You will find that some things are already being done, some areas are relatively easy and some very hard. You can get ‘free’ points for the rainwater harvesting, low-energy lighting and solar panels installed for other reasons, and pick up cheap points for installing a rotary clothes dryer in the garden or putting recycling bins in the kitchen. If you have a room called a study, it can qualify as a ‘home office’; if you have a garage with room for a bike or two it can qualify as a secure cycle store. There are likely to be many things that you plan to do anyway that with little or no change can gain points. Reducing the ecological impact of the house may not be on the agenda and can be very difficult and expensive – as a minimum it needs a comprehensive report by an ecological expert – and may best be avoided.

The answer is to do your homework and find all the free and cheap points that are available before moving onto the areas that can be expensive or require significant change to your plans. Recent Government research indicated meeting Level 6 (i.e. zero-carbon status) will add another £47,000 to typical build costs. Whether hitting Code Level 3 is a good idea or not is open to question — but also rather beside the point. The fact is that all new houses from 2016 (2011 in Wales) will need to be Code Level 6. Maybe Code Level 3 can be seen in a positive light as an easy ride into a more difficult, but necessary, goal.

CODE FOR SUSTAINABLE HOMES FAQs

What is the Code for Sustainable Homes (CSH)?

The CSH measures the sustainability of a new home against categories of sustainable design, rating the ‘whole home’ as a complete package. The CSH uses a one to six star-rating system to communicate the overall sustainability performance of a new home. It sets minimum standards for energy and water use at each level and, within England, replaces the EcoHomes scheme. It aims to give guidance to housebuilders to meet, step by step, the requirement for all new homes built in England to be zero-carbon by 2016 (2011 in Wales).

What about Scotland?

Scotland doesn’t use the Code for Sustainable Homes but The Sullivan Report, the result of a panel chaired by a leading Scottish green architect, made recommendations to develop a strategy to achieve zero net carbon emissions (i.e. the UK Government’s definition of zero carbon) within ten years “if practical” and total-life zero carbon by 2030.

How will the CSH be introduced and how will it affect me?

Level 3 of the CSH – equivalent to a 25% improvement in existing Building Regulations standards – was introduced into the 2010 changes to the Building Regulations. Level 4 (44% improvement) is due to be mandatory by 2013, and Level 6 (a 100% improvement and a completely zero-carbon home) is due by 2016.

How to get assessed

A Code assessment is, perhaps unsurprisingly, a bureaucratic process, involving lots of paperwork — but is necessary to allow Building Control to issue the completion certificate. Talk to the assessor at the outset and find out exactly what documentation will be needed. Assemble all the necessary plans, specifications, certificates, invoices and the manufacturers’ brochures as the project progresses. This will reduce the time and effort the assessor has to put in, and reduce the assessor’s bill.

THINGS THAT YOU'LL NEED TO MEET LEVEL 3

RENEWABLES: If the design is struggling to get the 25% improvement needed, then adding a solar PV system contributing to the electricity demand goes a long way to solving the problem. Alternatively a biomass boiler will have net zero CO2 emissions.

LOW-FLOW SHOWER: Reducing your water usage by 33% every day won’t be easy — but fitting devices such as lowflow showers can make a significant difference to the equation, as will aerated taps. As for baths, you’ll need to think how to offset them as they are viewed as water-intensive

A HOME OFFICE: An easy way to score extra points with the CSH assessors. Even if you’re planning a study, put it on the plan as a ‘Home Office’ — and you’ll get an extra 1.2 points.

COUNCILS INSISTING ON LEVEL 3 NOW:

• Shropshire
• Ashford
• Berkshire
• Gloucestershire
• Essex

…and many more (according to the DCLG, “the Code 3 minimum is being taken up across the country”).

A NEW HOME IN CARDIFF IS SUPER-EFFICIENT, BUT SHOWS UP THE PROBLEMS WITH THE CSH

This new self-build house in Cardiff (MAIN IMAGE) is built to Passivhaus standards, which claims to be the world’s leading standard in energy-efficient construction. They use efficient components, super-insulation levels, excellent airtightness and a whole-house ventilation system to achieve minimal running costs and maximum comfort throughout the year. Houses are deemed to meet the Passivhaus criteria if their total energy demand for space heating is less than 15kWh/m²/yr treated floor area. A CSH Level 3 home might only require 20kWh/m²/yr to comply, depending on comparison figures. While Passivhaus focuses on energy, it doesn’t deal with things like security, ecology, site waste and the other ephemera that the CSH is interested in — and as a result might be more ‘efficient’ but have a lower rating in the Code.

Updated February 2011

Further reading:

• Building Regulations: Part L Changes Explained
• How to Achieve Level 3 of the Code for Sustainable Homes
• Saving Energy in Your Self Build
• The Path to Zero Carbon