Energist - Part L Compliance Experts - Blog

Over the coming weeks we’ll be examining the upcoming changes to SAP and SBEM in more detail, which will hopefully give you a bit of a head start when these tougher regulations kick in come October 1^st.

This week we’re going to tackle thermal bridging and thermal mass – but first we need to understand what these terms mean.

Thermal bridging occurs wherever there is a break, gap or join in the insulation of a building. So that can occur where a wall and a roof meet, at corners, around window sills and door frames and between joists. Some thermal bridges are taken into account when the U-Value is calculated (such as where timber frame cuts through the insulation), but the bits known as ‘non-repeating thermal bridges’ have to be measured differently.

Why do they have to be measured – SAP measures the heating demand of a house. The more heat that can escape from a house, the harder the heating system will need to work, so SAP includes ventilation rates (to measure purposeful air holes), U-Values (to measure thermal efficiency of the envelope) and thermal bridging values (to measure the thermal efficiency of junctions in the construction.

As assessors, we currently have default figures to use - if you build to Accredited Construction Details or a similarly approved scheme, we can use one default value. If you don’t build to a recognised quality mark, we use a worse default value. The ‘value’ in question in like a U-Value, but is measured in a linear way, not area. It is called a psi-value, the lower the better.

Under the new SAP which fires up in October, the thermal bridging will need to be measured, rather than a default figure assumed. So, providing you build to a recognised scheme, we can calculate the perimeters, corner lengths and junctions of your dwelling, and provide a far more accurate result for the SAP Calculation. A worst case default figure will still be available.

So what can you do to make this figure as favourable as possible. There’s a couple of things… you can design dwellings with fewer junctions… you don’t need to go down the route of lighthouse buildings (as they don’t have corners), but less complex shapes and designs will help. Another way of lowering your psi-value is to get hold of the psi-value for individual insulation materials (this can be near impossible to find, but we expect the industry will start publishing this information once they realize this could earn them a few extra sales.

Another area of SAP which is moving away from defaults into accurate measuring is the ‘Thermal Mass Parameter’ or ‘How well a building stores heat during the day and releases into the home at night’. When compared to masonry builds, timber houses heat up quickly but don’t store heat for as long, so you use less heat during the day, but potentially more at night.

Currently SAP does not allow you to work out your own Thermal Mass Calculation, but this too is being altered. From the test studies we have completed, timber frame houses will fair better from this change to the methodology if built with a standard specification… if you are building a house with extremely low U-Values and ventilation rates, the masonry construction will fair better.

I hope that hasn’t confused you too much – out of all the changes to SAP, this is the toughest one to explain, I’m glad we’ve got that out of the way!

If you’d like any more information on the changes to the Part L Building Regulations please give Energist a call on 08458 386 387 to see how we can help.

As regular Energist blog readers will be aware, we’re currently bringing you weekly updates on the changes to Part L, which will effect SAP and SBEM calculations.

These changes are coming into play in October… or are they?

It was recently announced in Building Magazine that the Home Builders Federation (HBF) had written to Andrew Stunnell, the Building Regulations Minister, requesting that the introduction of the new Part L be delayed by 6 months to allow the industry more time to adapt to the changes.

To make sure you are fully up to date with all the facts, we have queried this information with one of our accreditation bodies, NHER. We currently expect Part L 2010 to be introduced – as planned – on the 1^st October 2010, as the Communities and Local Government (CLG) has not indicated otherwise. Our assessment software to be completed and approved before this date, which means any projects being handled by the Energist assessment team will be dealt with without disturbance or delay.

As there has been no announcement from CLG regarding this article, we will continue to hold Part L 2010 training seminars and provide guidance on how to pass the new SAP and SBEM regulations on the basis that the Part L changes will come into force on October 1^st.

If any official statements are made, we will of course issue an update here, on our site and inform all of out clients. Regardless, we believe it’s best to prepare for this deadline and find the date has been moved, rather than leaving ourselves and our customers caught short without the information and knowledge needed to comply.

If you’d like any more information on the changes to the Part L Building Regulations please give us a call on 08458 386 387 to see how we can help.

On this blog before we have covered the news that Part L is changing, that SAP and SBEM are changing with it, and that the energy efficiency of new buildings is going to be tightened up come October.

This is happening across the UK – but how much of a difference depends on where you live and what you’re building.

Let’s start with the residential market in England and Wales. Come October there’s going to be tighter U-Values limits, new U-Values which haven’t been needed before, tighter air leakage demands, more low energy lighting, better glazing specification, fewer exemptions, more attention paid to thermal bridges and thermal mass and, the big change: a 25% reduction on the Target Emission Rate.

Compare that to what’s going to be happening in the commercial sector in Part L2 for England and Wales. For SBEM calculations, most of the regulations are staying the same as before. U-Value requirements aren’t changing, heating efficiencies are staying the same… the only difference is the 25% reduction in the Target Emission Rate… but even that’s not going to be simple.

The 25% cut is going to be an average, based on the type of building being assessed – so some commercial developers will only need to reduce their emissions by 20%, others by 30%. It’s been known for some time that particular commercial buildings fair better in the SBEM calculation than others, this system is an attempt to iron out this problem, while reducing the limits on emissions at the same time.

Confused yet… let’s head over the border.

For residential developments under Section 6 in Scotland, the Target Emission Rate is going to be reduced ‘by approximately 30%’ compared to where it is now. ‘Approximately’ is how the Scottish Building Standards Agency has phrased it – they’re using the average approach (more commonly known as the aggregate TER) which is being used on commercial buildings in England and Wales. On top of this, the SBSA is also going to be offering guidance for improving the energy efficiency of existing buildings, encouraging a greater use of low carbon systems in new homes, lowering the maximum U-Values and from 2011 air leakage testing will be brought in for the first time.

Finally for now, Scottish commercial developments. Maximum U-Values are being lowered, and are going to be different to that used on the domestic side. The Target Emission Rate is going to see a flat 30% reduction (not based on an average system) and air leakage tests will be introduced in 2011. For commercial shells, the air test must meet seven with a secondary air test to be completed once the fit out stage has been completed.

Somehow, the technical team at Energist UK understand all the changes that are being introduced into Part L and Section 6 over the coming twelve months, and will be able to help you with any queries you have. Call us on 08458 386 387.

Firstly, I feel the need to offer huge ‘Congratulations’ to the brave team from Energist who completed a charity abseil last weekend.

MD Sarah Fenwick, sustainability expert Rosemary Bailey, Stuart Clark from the CSH team and Laura Pitcher from our Customer Service department managed to raise more than £1,100 for the Winston’s Wish charity – an organisation which helps bereaved children.

The abseil was down the face of the Eagle Tower in Cheltenham – the tallest tower block in the city stretching up fifteen storeys.

It’s not too late to donate! There’s always somebody in the Energist team looking to raise money for one charity or another. Keep in touch with us and we’ll let you know our upcoming fundraising events.

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Elsewhere in Cheltenham this week, Energist teamed up with solicitors, Rickerby’s, to offer a free training seminar covering BREEAM Communities and an update on the Government’s Carbon Reduction Commitment.

The morning was attended by a mix of fifty architects, surveyors, lawyers and people from across the construction industry, keen to find out more about how the new BREEAM scheme will effect the planning and development of future sites.

Attendees were also given an update on the CRC Energy Efficiency Scheme (previously known as the Carbon Reduction Commitment) which was launched in April, and is a plan to raise awareness in large organisations about energy saving measures and to encourage changes in behaviour and infrastructure.

In July, Energist will be hosting a training morning dedicated to the changes in Part L regulations, the effect this will have on SAP and SBEM calculations.

For more information about this and other training sessions which are available, contact our Customer Support team on 08458 386 387.

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The final story of the week looks at the Government announcement of a series of cuts which has instantly hit a number of grants for installation renewable technologies in the home.

The Department of Energy And Climate Change has had its budget cut as part of the coalition Government’s saving plans. It means that, with immediate effect, there are no grants available for installing heat pumps or solar panels.

Grants for using photovoltaic panels or wind turbines were scrapped under Labour, with a Feed-In Tariff introduced to replace it.

It’s thought this announcement will put a dent in the amount of renovation projects using renewable technologies, but it isn’t expected to have such an impact on new build developments, which are being forced to use more energy efficient means of fuel by building regulations.

Last week’s blog talked about how the new coalition Government in England and Wales will be abolishing the Home Information Packs for people who are looking for move or sell their house.

Within a week of Cameron taking over, the documents have already been suspended – after Eric Pickles (our new Communities Secretary) brought an Order to Parliament this morning. The packs will now be scrapped completely in due course.

As mentioned previously, the Energy Performance Certificate will still be required – this document, which shows the energy efficiency of a building – must be produced before it can be sold or leased. The reports last for ten years and are issued as standard for all new buildings.

It is less widely known that commercial buildings (everything from pubs to offices, warehouses to care homes) also require Energy Performance Certificates when sold or leased. Publicly owned buildings (such as schools, hospitals, police stations) are required to show a Display Energy Certificate at all times, if they are over 1,000 square metres.

Just to clarify, an EPC shows the predicted energy use of a building based on a site inspection or from architectural drawings (if it’s new). The certificate uses the A-G scale as you would find on white goods. A Rated is good, G Rated is bad.

A DEC certificate shows the actual energy use, and is based on fuel bills from the last twelve months. So logically, if you go into a council building and look at their certificates, the EPC says the building should be a C-Rated, but the DEC says it’s actually F-Rated, you know people aren’t switching the lights off at night!

If you own an existing commercial building, and have been asked to produce an EPC, you’ll find it is much harder to locate an energy assessor to complete your site surveys. Domestic Energy Assessors need additional qualifications in order to assess a commercial building – you’ll also find having commercial surveys done is more expensive… as the buildings are generally far more complicated.

Within the Energist assessment team, we have fully qualified Commercial Energy Assessors who are able to produce EPC and DEC reports for existing commercial buildings, as well as SBEM and BREEAM assessments for new builds. Our commercial team can also produce Daylighting Calculations, Energy Statements and Air Testing.

For more details about how Energist can help you with your commercial building projects, contact our Customer Support team on 08458 386 387.