Smart Retrofit: Data Driven Design

Good morning everyone and welcome to todays webinar. My name’s Keira Proctor, managing director here at the A. Proctor Group and this our 16th webinar of 2021. If you’ve missed any of series, which has been running since April 2020, you can go back and review them all on-demand either here on our YouTube channel, or on our learning hub at www.proctorgroup.com.

If you would like CPD certification for today or any of our other sessions, you can also register for that, access product information or book in for a follow up meeting with our team of expert either online or in person.

Today we are joined once again by a very special guest presenter, Stewart Little, CEO of IRT Surveys. Based in Dundee, IRT are specialists in assessing and optimising energy performance and upgrade of existing buildings, and Stewart will be discussing the use of these technical to drive smart, cost effective retrofit projects.

Before that though, we’ll take a minute to briefly review the background to todays retrofit requirement and some of the frameworks and documents involved in these projects.

As usual, we’ll finish up with a Q&A session where Stewart will be taking your questions alongside our team of experts. You can type question into the YouTube chat box, DM on twitter @proctorgroup or drop us an email to webinar@proctorgroup.com.

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In term of the UKs progress towards net zero, 2021 is notable for a number of reasons.

The UK government in 2019 announced it’s intention to target net zero CO2 emissions by 2050, however progress towards environmental targets have historically been slower than necessary. The UK is also hosting the COP26 conference in Glasgow this November, placing a global spotlight on these efforts.

The effects of lockdown and reduction in travel have also been significant, with the Committee on Climate Change (CCC) June 2021 progress report showing that UK CO2 emission dropped by 13% in 2020, to almost half the 1990 emission baseline.

While this reduction and the conditions leading to it are unprecedented and likely not sustainable over the coming years, ensuring some of the positive changes are locked in and taken forward is an important component of “building back better”.

DECARBONISING BUILDINGS

While reductions in transport related CO2 emissions have been hugely reduced, and working form home and the reduced need for business travel seem likely to result in at least some degree of permanence there, progress on building stock has been less positive.

The rate of insulation upgrade work in the UK peaked in 2012 and remains well below necessary levels, not least as the pandemic largely halted the retrofitting of occupied dwellings. The 2012 peak did however correspond with the end of the CERT/CESP programmes of subsidised upgrade work, illustrating the potential of effective policy as a driver.

Several programs and frameworks are currently underway or under discussion with a view to boosting progress in the construction sector. Proposals are under consultation across the UK regarding increasing efficient of owner-occupied and privately rented housing to a minimum of EPC band C rating by the 2030’s, and the Future Homes standard is due for introduction in 2025.

We’ve discussed the future homes standard for new builds before in a webinar last year, which can be viewed on-demand at our learning hub.

On the retrofit side, there is also the social housing decarbonisation fund, a “spiritual successor” of sorts to CERT and CESP, announced as a demonstration in 2020. SHDF aims to increase efficiency across the socially rented sector to at least EPC band C, and to date a budget of over £200 million has been allocated to it's delivery.

SHDF WAVE 1 PRICIPLES

There are three key principles of the SDHFs first wave of projects. Lesson learned from the delivery of these will then be incorporated into future waves of the project.

Worst First

Firstly the project is structured such that a scaled cost cap allows more for greater spending on properties with the lowest EPC bands. The reflects the greater challenges that are often present in low performing properties.

A common feature of these types of dwelling are solid or otherwise hard to treat wall constructions, which regular viewers of our webinars may remember we’ve covered previously. Our range of Spacetherm aerogel insulation systems are ideal for space-efficient thermal upgrades of these types of property.

Fabric First

The fabric first approach to construction is based on ensuring heat loss from the dwelling is minimised as far as possible prior to the application of other energy efficiency measures. Targeting upgrades in this way ensure a solid foundation is laid for future upgrade works to build on.

Taking this approach would, for example, prioritise effective thermal insulation, air leakage prevention and quality glazing over lower carbon heating systems.

Systems such as our spacetherm are very effective in this approach, as their minimal thickness allows for the insulated envelope to be as continuous as possible around doors and window reveals and in area with limited space.

Our Wraptite vapour permeable air barrier system can also be combined with insulation upgrades to deliver reduce air leakage rates without compromising the moisture transfer characteristics of the structure.

Lowest Regrets

The final principle is that any approach taken should seek to minimise the potential that any measure installed will require replacement on the way to meeting the net zero target. So nothing should be undertaken as a simple stop gap measure, and it should be possible for any future work to build on what is done now..

SHDF Aims

Based on these principle the scheme aims to reduce the number of social rental tenants in fuel poverty. In England and Wales this is defined as having a household income below the poverty line after energy costs, and higher than average energy cost for the dwelling type. In the rest of the UK a simpler definition of spending 10% of household income on energy is used.

The target of EPC band C will reduce the energy costs, and thus aims to reduce fuel poverty while at the same time reducing the dwelling CO2 emissions, the second stated SHDF aim, and improving the “comfort, health and wellbeing” of tenants, which is another of the aims.

The last aim of the fund, is to boost economic resilience in response to COVID by supporting jobs and industries via a green recovery.

FRAMEWORKS

In order to ensure a best practice approach to upgrade works, SHDF funded projects must use the PAS2035 Specification, which details the steps, assessments and risks associated with each stage of the process from assessment and design through to completion and handover.

It specifies requirements in the following areas:

Assessment of dwellings for retrofit

Identification and evaluation of improvement options

Design and specification of energy efficiency measures (EEMs)

and the Monitoring and evaluation of retrofit projects

The ultimate aim of the standard is to ensure projects deliver a healthy and fit more purpose environment for the occupants while respecting any preservation considerations. This makes its principles a good fit with the aims and principles of the SHDF.

Our refurbishment webinar which can be found on our learning hub goes into a lot more detail about PAS2035 and how it can be applied to domestic refurbishment projects,.

EVALUATION

What is critical across all these approaches and measures is developing a solid understanding of the performance levels before and after upgrade works. Not least because the “As Designed, Theoretical” or ADT conditions assessed in the calculation methods may not match the “As Built, In Service” or ABIS conditions as well as would be ideal.

So it's important that the fabric performance is properly and thoroughly assessed to ensure the buildings are not only performing as intended post upgrade, but also to understand what we are dealing with during the design stage.