Energist - Part L Compliance Experts - Blog

This week, BRE has published the SAP2009 document. This will replace the current SAP Calculation for any dwellings which go through planning as of October of this year. It is the biggest change to Part L since 2005 and is the next step in the Government’s drive to ensure all new build homes will be carbon neutral by 2016.

The first thing to say on this, is these changes will not effect any projects you are currently working on – providing you go through planning approval in the next six months.

Here are some of the big changes you should be aware of…

PARTY WALLS: Up until now, SAP has ignored the walls between dwellings. This is going to change as it’s been discovered that more heat escapes through these walls than previously thought. For example, an uninsulated party wall without edge sealing will be assumed to have a U-Value of 0.5. Bearing in mind this will be combined with the U-Values for the external walls, and that combined value will still need to be better than 0.35, it makes sense to insulate between houses.

FUEL FACTORS: This is a way of judging how environmentally friendly each type of fuel is and includes creation, transportation and end use efficiencies. The emission factor for electricity is going to be increased by 40% making it much more difficult to pass a SAP using panel heaters. Meanwhile fuels such as biomass are seeing a reduction in emission factors, so there will be more of an incentive to use this kind of technology.

CONSTRUCTION: This is being brought in from Northern Ireland assessments. A masonry built house has a greater mass than a timber frame, so it traps heat in the walls better, slowly releasing the heat back into the building. SAP 2009 will be taking this into consideration.

TARGET EMISSION RATE: This is being lowered to bring a standard SAP assessment down to the level that a Code for Sustainable Home Level 3 house is today. This will mean an emission saving of 25% will be needed on all new homes when compared to the current SAP assessment.

HEATING: Details about heating, cooling, ventilation and heat recovery systems are being updated to allow more information to be included in the SAP assessment.

WATER USE: A cap of 125 litres of water per person per day is being imposed on new builds under this new regulation, although it’s not clear how this limit is going to be policed.

As you can see Energist’s assessment team is already getting clued up about these changes, so we will be completely up to speed by the time this document becomes a legal requirement in October.

Call us for more information on 08458 386 387.

It’s becoming quite clear to us that there’s a big buzz in the industry around the idea of building to the PassivHaus standard. But what does that mean? Here’s a quick run through:

PassivHaus is a way of measuring the heat loss of a building (domestic or commercial, old or new) with the aim of maximising efficiency through insulation levels and air tightness – the first PassivHaus was built twenty years ago in Europe, but the idea is only now filtering into the UK.

We would expect a Passivhaus to record an air leakage result of less than one. Current new build houses in the UK are achieving around the 6-7 mark… U-Values of a PassivHaus wall would be less than 0.15 – half of what is typical in the current market… Mechanical ventilation and heat recovery systems tend to be fitted as standard… all of this combined pretty much eradicates the need for a heating system, (although don’t quote us on that given Blighty’s climate!)

The process of completing a PassivHaus calculation has similarities to the mandatory SAP calculation in the UK, an Accredited piece of software must be used to record U-Values, efficiencies and air tightness. Whereas SAP records a total emission target for a building, PassivHaus is based on the overall energy demand.

If you’re tempted by the idea of building to PassivHaus standard, you need to remember that this practice is only voluntary in the UK, but the SAP assessment is mandatory! And despite having some similarities, it can be incredibly difficult to design a building which meets all the aspects of both SAP and PassivHaus combined!

The assessment team at Energist is able to help you with PassivHaus queries, offer consultancy sessions and even complete the PHPP assessments. Or, if this has scared you off the idea of PassivHaus and you just want to stick to current Building Regs, we can provide a Guaranteed Pass on all new-build SAP assessments!

Call 08458 386 387 for more information.

Just recently, the Energist assessment team has received an increase in queries about Energy Statements (or Feasibility Studies). There’s a lot of confusion about what they are… what they show… and why they exist! So here’s a quick explanation to make things clearer:

WHAT IS AN ENERGY STATEMENT?

A growing number of planning departments in England and Wales are looking for ways of making new buildings – both domestic and commercial – more energy efficient. This is on top of what is currently called for under current Building Regulations. This trend started in the borough of Merton where all new buildings were required to show a 10% improvement over the Part L emission rate, through the use of renewable technologies. This scheme was adopted into The London Plan and has spread across the country in recent months. Merton Council has now raised the game by requiring a 20% reduction on emissions. We find most councils require a 10% reduction on emissions, some ask for the reduction to be shown in energy use instead.

WHAT DO WE MEAN BY ‘RENEWABLE’?

Energy Statements are not based on a nationwide model and councils are free to decide what can be considered renewable and what can’t. The most common forms of renewable to be considered are solar panels (for hot water), photovoltaic panels (for electricity generation), wind turbines (for rural, hilly locations), ground source heat pumps (interestingly not air source), biomass heating systems and micro CHP (combined heat and power) boilers.

HOW DO I CREATE ONE FOR MY COUNCIL?

Good news! Energist can complete your L1/L2 Calculations AND produce a thirty-page Energy Statement for your site which will comply with your council’s requirements! We will check your site against the six forms of renewable technology mentioned above and let you know which ones are feasible, if any. This information will be clearly shown in the tailored report which will be sent direct to your inbox.

For more information about this service, call Energist UK on 08458 386 387.

THIS WEEK, TENS of thousands of professionals from the European building industry attended the EcoBuild exhibition at Earl’s Court to gain an insight into the latest developments in building materials, renewable technologies, heating systems and building legislation.

So what did the Energist team uncover in among the thousand plus exhibitors and scores of seminars?

“EcoBuild was launched 5 years ago, and the attendance was 950 visitors in the first year.  This week, the 2010 EcoBuild had over 55,000 visitors, with 25% more exhibition space than 2009.  This surely demonstrates the size of the green and sustainable market – which gives us a glimpse of a no doubt challenging but also exciting future” Sarah Fenwick, MD, Energist UK

-          There was a heavy ethos on PassivHaus among developers and accreditors. This is despite there only being a handful of live projects currently on the go in the UK. PassivHaus is used more widely in Europe as an alternative way of gauging energy efficiency in buildings, with the emphasis on air tightness and insulation to keep heating costs to an absolute minimum. If you would like more information on PassivHaus developments, call us for more information.

-          Mechanical Ventilation systems – which channel warm air from wet rooms, filter it and recirculate around the rest of the house – have come on leaps and bounds in the past couple of years. Again, the benefit here is a more constant internal temperature and higher air tightness; although there are murmurs that developers are not convinced that these systems are being used correctly by the people who live in the houses, causing the dwelling to be less efficient.

-          Plenty of building materials and insulations on show from polystyrene blocks to walls made of hay and hemp. This can be a confusing juggling act for those responsible for sourcing materials for building… is it cost effective? Does it have a good conductivity? Are the materials sustainable? Do they degrade over time? Can it be damaged easily? How will it effect the SAP and SBEM calculations? We’d recommend putting plenty of research into new construction methods if you haven’t used them before to make sure they’re appropriate for your site.

-          There are plenty of bodies out there eyeing up the future of Building Regulations in the UK. Short term, the SAP Calculation is going to get tighter (starting with a 25% emission cut from October) with the ambition that all new build dwellings are carbon neutral by 2016, and all commercial buildings by 2019. And then the longer-term plan is to turn our attention to the existing housing stock to see how we can cut our emission rates even further.

What thoughts did you come away with from this year’s Ecobuild? We’d love to hear them!

Remember that Energist can help with Air Tightness Testing, SAP and SBEM Calculations; Code for Sustainable Homes, Energy Statements, PassivHaus, Sunlight Feasibility Reports, BREEAM, Commercial Energy Performance Certificates, Display Energy Certificates, the list goes on…. Call us on 08458 386 387 to find out how we can help you meet your Part L sustainability needs.