Energist - Part L Compliance Experts - Blog

We’ve got three weeks to go until the new Part L Regulations kick in, with new SAP and SBEM methodology coming into play also – so we thought it was about time we had a bit of a Q&A session:

If you can make it to our Gloucestershire offices on the morning of September 30^th, we are holding a FREE breakfast seminar to go over what is changing. For more information, contact our Customer Support Team on 08458 386 387.

Will my next project fall under the new Regulations?

If the planning notice for your development is submitted before the 1^st October, your site will be treated under the 2006 Regulations. This means you can have a SAP or SBEM completed under the current Regulations. This calculation will be valid even when the new Regulations kick in. The only catch is that you must start work on site within twelve months. Given the additional work you will be required to carry out under the new regulations, it makes sense it get your paperwork into the planning department as soon as you can.

Can you define ‘starting work’?

As long as you’ve broken ground on site, you can be classed as ‘starting start’… maybe this involves laying the foundations for a plot, or installing underground pipework. If you have submitted plans for a large development, you don’t need to have started work on every plot within this twelve month leniency time. The Communities for Local Government (CLG) have further guidance on this.

Will this regulation change affect my SAP and EPC ratings?

Since both the regulations and the calculations are changing, there will be some noticeable differences if you were to compare reports under both old and new regulations. It is important to remember that you won’t need to worry about retrospectively complying with the new regs – this will only apply to new sites which are lodged with planning from October onwards. The only change you may notice is that your Predicted Energy Assessment (PEA) which is issued at Design Stage may show a different reading from your Energy Performance Certificate (EPC) which is issued at As Built Stage… although we do not believe this show any substantial differences.

                Is there any free reference material about the changes to Part L?

You’ve got two options there – Energist will shortly be publishing our 32 page guide to the regulation changes which covers all areas, including L1B and commercial. This will be available to all existing customers. Alternatively, you can download the official Government legislation from the CLG, from Planning Portal and from BRE. Get in touch if you’d like a copy of our booklet, which we’re aiming to have published in time for the new regulations

                Is it true that EPC’s cannot be issued under the new legislation until the end of March?

At the moment, that is correct. This will only effect developments which are submitted to planning after October 1^st, but require their As Built certificates and EPC’s before March 27^th… so we’re only talking about the Speedy Gonzalez’s of the construction industry. It will be possible to produce the Regulation calculations under the new software, and produce the EPC under the old software during this transitional period.

Any other questions, send them over, or call Energist on 08458 386 387.

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 travelling north of the border, and looking at the changes which are going to be imposed on Scotland when the new Section 6 goes live – this will also be on October 1^st in line with the new SAP methodology and the new Part L.

The biggest change to Section 6 is the Target Emission Rate which is being tightened. Overall, the emission rate is being lowered by 25%, but this percentage will vary depending on the type of dwelling being built (so some houses will need a 30% reduction compared to current figures, some will only need 20%, but the national average will be 25%). This is known as the ‘Aggregate Method’ for calculating the Target Emission Rate and is being used by the new SBEM method in England and Wales.

Air Leakage Testing is another big change – but this isn’t coming into play just yet. Air tests are now commonplace at new developments in England and Wales; they are currently voluntary in Scotland. From May 2011, air tests will become compulsory for small dwellings, followed by all dwellings in October 2011 – around 5% of new houses will need to be tested.

Limiting U-Values are being reduced – walls will need to achieve an average U-Value of 0.25, ground floors will need to be 0.2, roofs 0.18 and glazing / rooflights 1.8 – these figures are lower than what is required in England and Wales.

To make things slightly more confusing, U-Values are different if you are planning a conversions project to create a new dwelling – the most noticeable change is a maximum U-Value of 1.6 for all windows, rooflights and external doors. Extension projects will fall under a third band of U-Values!

Thermal bridges are going to affect Scottish SAP Calculations more than ever before, assessors will need to look more closely at areas of a building where insulation overlaps. The Accredited Construction Scheme from the Energy Savings Trust gives more information about what building practices are required in order to comply with this section.

The minimum efficiency of heating systems is being increased – boilers running on mains gas, oil and LPG must be A-Rated for all new developments – oil combi’s can be B-Rated.

When it comes to lighting, three quarters of all internal light bulbs must be low-energy, and 100% in communal areas, such as stairwells of flats.

As this list of highlights shows, the new Section 6 is going through some substantial changes in a bid to reduce carbon emissions in Scotland. To find out how Energist can help you with future developments, call our Customer Service team on 08458 386 387.

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 look at heating, cooling and ventilation systems, and how your SAP calculation can be dramatically affected by the heating system you choose for your dwelling.

We’ve already covered fuel emission factors in a previous posting (which explains why different fuel types have such an impact on emission rates) so feel free to look back and catch up with us on that section!

As assessors, when we are completing a SAP (or SBEM for that matter), we have a list of dropdown boxes and options which we use to most accurately reflect the heating system to be used in a building.

This is fine for a standard house with a standard boiler, but when you get into the realms of a twelve bedroom mansion with a heat pump, separate boiler and immersion back-up, the SAP methodology doesn’t take account of the full picture.

SAP2005 can only deal with one main heating system per plot, one type of water heating and one type of secondary heating (which is either a fireplace, log burner or decorative fireplace. We can only enter one type of ventilation system (either standard extraction fans or a mechanical ventilation system) and there is no scope for entering comfort cooling systems. Also, currently heat pump efficiencies cannot be entered – SAP will always assume default figures which are usually higher than the actual product.

When the new Part L kicks in, SAP is being enhanced to give us (the assessors) a bigger array of options for the calculation… which will help to give more accurate figures overall.

The new SAP will allow two separate heating systems to be entered for one dwelling… if a heat pump is involved, we will be able to enter the actual efficiency (the co-efficient of performance) instead of having to make do with the default figure. Also, there will be the ability to enter two types of ventilation system – this will benefit large buildings which have heat recovery in some areas only.

Another change will be the introduction of cooling systems into SAP. If you are planning on installing a cooling system, your energy use will go up (which makes sense… the current SAP ignores them completely), but there’s a bit of a twist….

The assumed use of the cooling system will be geographically specific – in other words, SAP will predict the cooler will need more power in Cornwall compared to the Isle of Skye because of the change in climate. So the further south you go, the worse emission rates you’ll get. Interestingly the same does NOT apply to heating systems, although there are rumours this will be included in the next revision of SAP methodology.

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

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.

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 are focusing on lighting – there’s some important changes regarding high efficiency lighting for new residential developments, and we don’t want to keep you in the dark about them (comedic symbol crash). This change does not affect commercial developments.

Under the current SAP guidance in England and Wales, any new building must have either:

-          25% of the total light fittings must be low-energy exclusive

-          OR – there must be one low-energy light fitting for every 25m2 of useful floor space – whichever figure is greater.

A couple of things to clear up – by a ‘low energy fitting’, we are referring to a light socket which will only accept fluorescent bulbs or energy-saving bulbs… standard bayonet or screw fittings do not count. Low energy is defined as anything better than 40 lumens per watt. Energy savers are around the 60-80 mark, standard tungsten and halogen bulbs are between 15 and 25.

Also, we are talking about low wattage bulbs – these are not the same as low voltage bulbs (such as halogen downlighters) which have a similar efficiency to a typical tungsten bulb.

Lighting is treated in a strange way by SAP… if you fit your house with 100% low energy fittings, you’ll get a better EPC rating, but your Design Emission Rate will stay the same. This is because the SAP methodology is currently fixed on a 30% assumption. The EPC calculation greater reflects the reality.

So, that’s where we are now… this is where we’re going under the new SAP method…

The amount of low energy lighting is increasing to 75% - so three quarters of light fittings in new buildings will need to be low energy. But this doesn’t mean you’ll need to buy expensive low-energy fittings… you’ll be able to use standard bayonet fittings throughout the house, as long as you fit 75% of them with energy saving light bulbs.

With the phasing out of traditional tungsten lamps, it’s less likely that people are going to replace energy savers with the old fashioned lights, so the idea of having ‘dedicated’ fittings is being removed.

Also, the more energy efficient bulbs you use, the better your Design Emission Rate will be and the better EPC rating you will get – the current 30% assumption in SAP is being removed.

One final note – the definition of ‘energy efficient lighting’ is being changed from 40 lumens per watt to 45… but as long as you fit the house out with A-Rated lights (as all compact fluorescents are) then you won’t have a problem here.

If you’d like any more information on the changes to the Part L Building Regulations please give us a call on 08458 386387 to see how we can help.