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In2science UK CBG Workshop – starting a career in STEM

We are working in partnership with the charity In2science UK. Due to poverty and social background being huge obstacles for young people to obtain a career within the STEM industry, the charity sets out to help overcome these barriers. Working with industry professionals, In2science UK provides young people from low-income and disadvantaged backgrounds an opportunity to gain practical insight, knowledge, and confidence. Students work alongside and attend workshops hosted by industry professionals.

We have set up a workshop and present to a group of 16-18 year old students who are interested in starting a career within STEM.

The structure we lay out for our In2science UK workshops are as follows:

Key questions we get asked from students are:

Try to attend a summer vocational placement to make contacts and understand whether you enjoy the industry. Microsoft Excel is a very useful tool for calculations and efficiently analysing data, so we recommend that students obtain a good knowledge on its abilities.

The Khan Academy has numerous free online tutorials on various STEM subjects.

New regulations (June 2022) have just been put into place and as a company, we are trying to learn how they will affect our future designs. In 2025 the ‘Future Homes Standard’ will be released, and this will change how we design domestic buildings.

 

The feedback that we have received from attendees after our workshops:

For information on how you can volunteer for In2scienceUK and inspire a young person into STEM click here

Phasing Out the Installation of Fossil Fuel Heating in Homes

The government has released a consultation on the phasing out of fossil fuel heating in homes off the gas grid.

This consultation sets out proposals to phase out the installation of high carbon fossil fuel heating systems in homes, as committed to in the 2017 Clean Growth Strategy.

Here are some of the key proposals for the sector from the report

This consultation was launched alongside the Heat and Buildings strategy.

The government is looking for responses from the heating industry, consumers and those with a wider interest in the UK’s net zero ambition to help shape the design of the policy. Please feel free to provide your response to the consultation questions here. The closing date for the consultation is 12th January 2022.

Please contact our sustainability team if you need any assistance to understand low carbon heating options. We offer a wide range of services including carbon appraisals and Low and Zero Carbon feasibility studies where we can provide advice early on in the design.

Earth Day 2021

Net-Zero is an ambitious target for governments, companies and institutions to dramatically reduce environmental impact and to prevent the most damaging effects of climate change. Significant cuts in emissions across the built environment are required in achieving this goal.

At CBG Consultants Ltd, we create buildings that minimise their environmental impact. We have a wealth of experience in thermal modelling which enables us to understand the performance of a building through a computer-generated model to assess energy consumption and carbon emissions.

Understanding how buildings generates carbon emissions and the predicted impacts of various measures and strategies through detailed modelling will generate a robust route map to Net Zero Carbon.

Remember, it’s up to us all to fix this climate crisis. Take your first step by visiting WWF’s carbon calculator to understand your carbon footprint and take actions.

The New London Plan 2021

After more than three years in the consultation process, the New London Plan came into force on 2nd March 2021.

The Plan sets the overarching framework for how London will develop over the next 20-25 years. It gives focus on new developments and redevelopments to meet low carbon, energy efficiency and sustainability standards as part of a drive to make London a zero-carbon city by 2050.

For further information, please visit ‘The London Plan 2021’

Our team have extensive experience supporting projects through the planning process on major London schemes and advising on the policy requirements. We can provide a full range of MEP and sustainability services in all areas of the built environment.

For information on the adopted changes and how they may affect your project, please get in touch!

© Greater London Authority

 

UK Climate Change Committee – Sixth Carbon Budget

Last week the UK Climate Change Committee (CCC) published their recommended Sixth Carbon Budget as part of the UK’s path to net zero carbon by 2050.

The advice is a reduction in UK greenhouse gas emissions of 78% by 2035 relative to 1990. This would achieve well over half of the emissions reduction required by 2050 in the next 15 years. The analysis in the report shows this is feasible, provided effective policies are introduced across the economy without delay. The budget requires a major investment programme, worth around £50 billion each year from 2030 to 2050. However, the CCC estimates net costs of meeting the budget to be low, equivalent to less than 1% of GDP.

The report covers every section of the economy including buildings. Specific actions for the buildings sector include:

To make all buildings energy efficient and ultimately low-carbon a clear timetable for policy standards is needed along with industry changes to rapidly scale up supply chains for heat pumps and to develop the option of hydrogen for heat.

CBG applies these principles with a ‘fabric first’ approach to reduce energy demands by focusing on passive design. Then it is followed by the design of efficient buildings services.

We keep up to date with all building regulations and policy guidance and can provide CPD presentations to assist with the transition to low and zero-carbon buildings. Please do contact us to schedule a CPD for your team.

Minimum Energy Efficiency Standard (MEES)

The Minimum Energy Efficiency Standard (MEES) came into force in England and Wales in April 2018, these standards apply to private rented residential and non-domestic properties.

The aim of the MEES is to encourage landlords and property owners to improve the energy efficiency of their properties by upgrading fabric, installing new boilers and energy efficient lighting etc.

Properties with EPC ratings of E or less will be subject to restriction on the granting and continuation of the existing tenancies .

Domestic Property

Minimum Energy Efficiency Standards (MEES) applies to any privately rented property which are legally required to have Energy Performance Certificate (EPC), these include assured short hold, regulated and domestic agricultural tenancies. From April 2018, landlords will not be able to grant a tenancy to new or existing tenants with an EPC rating of F and G and from 1 April 2020, they’ll not be able to continue letting the property without improvements.

Landlords are not expected to finance the cost of improvements but to use third party resources such as Green Deal and Local authority improvement grants. Exemption can be claimed where they are not able to get the funding/grant to cover the cost of the improvements, or are not able to achieve the minimum EPC rating (E) even after improvements. Any exemption must be registered on the RPS Exemption Register.

Non-Domestic Private Rented Property

Similarly, as above from 1 April 2018, non domestic landlords must not grant new tenancies without the minimum energy efficiency standards. They cannot continue to let the property after 1 April 2023 where property has an EPC rating of below E.

All the improvements to Non-Domestic properties will be funded by landlord or tenant, there is no third-party funding available. Landlords may be able to claim exemption, all exemptions must be registered on the RPS Exemption Register.

We have a team of Qualified Level 3, 4 and 5 Energy Assessors, who can provide assistance with MEES compliance and provide advise on how to achieve MEES compliant building. Please do contact us should you wish to find out more.

A Sunny Afternoon in Oxford!

Always seeking an excuse to take a sunny walk in Oxford, Chris Dicks took time out between meetings for a stroll around the Thames and Christ Church Meadows, to look at a few current and former CBG Consultants Oxford projects.

First stop was the Cathedral at Christ Church, where we are nearing completion of the first phase of the new lighting project. Working with Purcell, Monard Electrical, and specialist designers, the project sees the replacement of energy hungry and failure prone halogen lights with high performance LEDs.

The next stop was our project completed with A2 Dominion and Yurky Cross, at Thames Street. Completed around 2015, this £8M project comprised of four residential blocks, with a mixture of social housing and student accommodation.

Continuing on the Thames waterfront, Chris checked in on our refurbishment project at Christ Church’s Boat House. Working with Robert Montgomery Architects, new changing facilities, gym, workshops, punt store and kitchen are being provided. Then it was on to the Jubilee Bridge, where CBG assisted Christ Church with infrastructure services to this elegant new footbridge, opened by the Dean in 2014.

After a pleasant walk through the Meadows, Chris reached the famous Broadwalk, along the sunny south site of Christ Church. We have worked on several major refurbishment projects with Sidleys Chartered Surveyors in the Meadows buildings over the years, including the main visitor entrance.

Finally, it was back to the iconic Tom Tower on St Aldates, housing the famous Old Tom bell. In 2011, CBG worked with the college to locate new hot water distribution plant within a spare corner of the tower, which was last open to the public in the 1930s.

Just time for a quick coffee at another Oxford institution G&D’s café, then on to the next meeting…

BREEAM UK New Construction 2018, So What’s New?

On Friday 23rd March 2018, the BREEAM UK New Construction 2014 scheme will close for registration and usher in the new era of BREEAM UK New Construction 2018.

Released on the 7th March, this new scheme looks to upgrade on BREEAM UK NC 2014, to improve the clarity of the technical manual for all users and give an added focus to the building’s life cycle in an overall more concise manner.

We have reviewed the new manual and below are a few of the major developments made by the BRE in BREEAM UK New Construction 2018:

Post-Occupancy Stage (POS)

The biggest development is the introduction of a new Post-Occupancy Stage, an optional third stage. This assists in assuring that the design performance targets are being monitored and reported to identify any deficiencies in performance and where required rectify; focusing primarily on the Energy and Water categories.

MAN 03 Responsible Construction Practices

Previously, this awarded two credits if a developer adopted a Considerate Constructor’s Scheme and achieved a score >35.

BREEAM UK New Construction 2018 has replaced this requirement with a checklist of 19 responsible construction management items of their own, although many of these can be covered by undertaking a compliant CCS.

Updating on the BREEAM NC 2014 manual, there is now a requirement not just to monitor energy use, water consumption and transportation data on site, but to also to set performance targets.

Transport 01/02

The Transport Category has had a complete facelift. Four credits have now been compacted into two; the first is awarded by producing a Travel Plan, which has had its own criteria update and the second has become an amalgamation of all the previous Transport credits from BREEAM NC 2014. A selection of 11 transport measures are provided, with credits awarded based on how many are implemented on site.

ENE 01 Reduction of Energy Use and Carbon Emissions

Previously the energy performance ratio (EPRNC) section of this awarded 12 credits, rewarding reduction in building energy use. However, this has now been reduced to 9 credits with a reduction in the size of the benchmark scale, whilst keeping the EPRNC score minimum standards for overall BREEAM ratings. This change has been introduced to encourage the uptake of the 4 new credits to encourages additional modelling and reporting energy consumption data.

MAT 01 Environmental Impacts from Construction Products – Building Life Cycle Assessment (LCA)

The major change in Mat01 is the removal of the Green Guide ratings, in its place is the BRE’s Life Cycle Assessment tool. This tool now includes the ranges of elemental descriptions previously found in the Green Guide, and will ultimately calculate the credits awarded.

Another option is the IMPACT Compliant LCA tool, which has a similar process but is integrated into BIM or IES software.

Furthermore, the BREEAM UK NC 2014, hard landscaping and insulation credits have been encompassed into the Mat01 assessment.

If you require any other guidance on the new 2018 manual or wish to speak to us regarding any potential projects that may incorporate BREEAM NC 2018, please do not hesitate to contact us.

Closing the Performance Gap in Non-residential buildings

There is an increasing awareness in the construction industry that buildings do not perform as expected in terms of energy and carbon emissions, an issue which has become known as the “performance gap”.

For example, in a recent study by Innovate UK, it was shown across a range of non-domestic buildings that carbon emissions were 3.8 times high than design estimates, and that energy use varied widely[1]. There are a range of possible causes for the performance gap in buildings. Here we outline a number of issues we have experienced and how they may be overcome in the design and construction of buildings.

Energy Modelling

For most new buildings a computer model will be produced to demonstrate compliance with Part L of the building regulations. This involves the use of approved software which calculates the carbon emissions of the building, which must be less than or equal to a target generated by the software. This provides a means of checking compliance with building regulations, but is problematic for predicting actual building energy consumption and emissions. The models contain many generic (and unalterable) assumptions about the building use and internal heat gains, and often simplistic methods of calculating system performance. We often find that models will predict heating demands lower than Passivhaus buildings, when we know the real building demand could be more than five times this amount.

Building-specific energy modelling is needed to be able to reasonably estimate building performance. The modelling must take into account the specifics of building use, appliances, fabric and building services performance. However, like all models, the accuracy of the results is limited by unknowns. Calculating lighting energy use, for example, is relatively straightforward, whereas predicting vending machine energy performance may turn out to be a wild goose chase! Some other areas of uncertainty, like the impact of thermal bypass in insulation, or thermal bridging, are discussed further below. Where uncertainties are identified, it is useful to identify the potential impact through sensitivity tests.

A key feature of the Passivhaus approach is that many uncertainties are simply designed out or eliminated by careful construction. Not surprisingly, Passivhaus buildings can be successfully modelled using an excel spreadsheet.

Insulation & Thermal Bypass

The energy performance of building elements such as walls is calculated by reference to the “U-value”, which describes the amount of heat passing through 1m2 of surface. This value is theoretical, and assumes that the insulation has been fitted perfectly over the element. Thermal bypass describes a number of mechanisms by which heat can bypass the insulation layer, and results from imperfections in the installation. Additional heat loss is created when there are gaps between insulation boards or behind insulation boards, or in the worst-case scenario, both.

Some specific examples include;

The effect of thermal bypass can be significant- potentially resulting in heat losses being triple what was calculated[2]. In many cases the effect cannot be quantified- so it is best to avoid as far as possible.

How can thermal bypass be avoided?

In design;

In construction;

 

Thermal bypass Examples: Left: Gaps between insulation boards allow air and heat to bypass the insulation layer. Right: insulation boards not joined at the corner resulting in thermal bypass. Gap behind board on left will also allow air circulation.

 

Thermal Bridging

In non-residential developments, thermal bridging is rarely given attention, despite building regulations requirements for “continuous insulation”, calculations of junction heat losses, and a system for site inspections[3].  In practice, the impact of thermal bridging is largely ignored, with only a nominal allowance made for it in the energy model.

The impact of thermal bridging becomes more significant for building’s with high levels of insulation, which would include buildings constructed to the latest Part L2A standards. Based on a simple 5x5m ground floor room, we calculated that with high levels of insulation, heat loss from thermal bridges could account for 28% of the total for the space, and therefore not considering them could result in underestimating the heat demand by 39%.

As well as increasing energy consumption, thermal bridges also create cold surfaces which can result in condensation forming internally, or within the fabric. Internal dampness creates ideal conditions for mould growth, with the associated health effects on occupants.

How can thermal bridging be reduced?

In design;

Heat losses for a 5x5m ground floor room, for different insulation standards. Thermal bridge heat losses based SBEM technical manual.

 

Results from a numerical thermal model of a ground to wall junction. Colours show the temperature through the junction.

 

 

Thermal bridging examples. Left: heat loss through the lintel above the window. Right: heat loss under the external walls around the perimeter of a building.

 

Building Controls

Controls for mechanical systems and lighting, if set up correctly, are vital for minimising building energy consumption, by providing energy-consuming services only when needed. Control strategies such as weather compensation of boilers, or free cooling in ventilation systems, can reduce energy consumption by optimising the operation of the plant itself.
However, it is tempting for services engineers to push for increasing levels of complexity in control systems, in pursuit of greater and greater energy savings. In reality such complexity is more likely to lead to poor performance, as the chances of set up problems increases, and the end user is left with a system they can neither understand or operate correctly. A balance is needed between simplicity and sophistication, which will be different for each project and application.

Some key questions to ask might be;

It is tempting to add increasing complexity to control systems to squeeze out as much energy reduction as possible, but the reality might be very different. As complexity increases, so does the chance of errors in design, setup, commissioning, and operation, which inadvertently increase energy consumption.

Data, data, data

It takes time in new buildings to optimise performance in terms of energy and environmental control, as well as flushing out latent defects. The availability of data from a BMS system is crucial for first quantifying performance issues and defects, and then monitoring subsequent improvements.
To provide such data, the BMS must be set up to log the required parameters, and then to store the data somewhere. Normally the BMS hardware itself will have limited storage capacity, so a suitable location on a server or PC hard drive must be found. Once data is obtained it must be analysed and compared against expectations to build a clear picture of the issues.

[3] – Approved document L2A, 2013.

See the Service page for more information on how we can help you design buildings and optimise them for comfort and energy efficiency.

 

The Price of Thermal Bridging

Thermal Bridging calculations can be the most cost effective way of reducing domestic carbon emissions.

What is Thermal Bridging

Thermal bridging refers to an area of a building that has a higher heat transfer than surrounding materials. These bridges often occur at junctions between elements, for example around a window. The resulting heat losses are captured by ψ-values, which are applied over the length of each junction.

How to Design for Thermal Bridging

The effect of thermal bridges can be mitigated with appropriately placed insulating materials. One approach is to follow standard details such as the BRE Accredited Construction Details. Where standard details are not used, thermal bridging calculations are required to assess the junction performance.

Capital Cost

The bar chart shows the capital cost of these measures per tonne of carbon saved.

The cost of offset payments used in the London Plan has also been included.

In this example, use of thermal bridging calculations was by far the most cost-effective way of reducing the carbon emissions.

Ongoing Cost Savings

The solar PV system on this project was expected to pay for itself in around 19 years (accounting for export and feed in tariff payments). However when compared to carbon offsetting this reduces to around 12 years.

Assuming a base case of poor thermal bridge design (as represented by ‘default’ thermal bridging in SAP), reduced fuel bills from improved thermal design should very quickly recoup the money invested. These measures will also last the lifetime of the building, where as other technologies (such as solar PV) have a more limited service life.

Making a carbon offset payment will never give anything back so the investment stays flat.

Conclusions