114 homes including 101 private sale and 13 shared ownership. The residential units are provided in three blocks ranging from two to 11 storey’s in height.

Great Eastern Quays is a development of 837 Units in Great Eastern Quays, Royal Docks London. 

FTSE 250 construction company Galliford Try approached us with a concern that had been raised over a potential overheating risk to one of the blocks of flats on this development. It had been suggested that the building may need a solar shading solution (in the form of blinds), to mitigate the overheating risk in various rooms at certain times of the year.

This type of building assessment includes a detailed simulation of a building’s internal and external heat gains. It includes gains from the heating and ventilation equipment and occupancy densities, as well as external solar gains through the use of location-specific climate and sun path data. The software then calculates the temperature in each room of the model every hour for a whole year. 

We were asked to fully investigate the potential risk of overheating within the building using this design modelling, and to find answers for the following:

  • Was there a risk of overheating within the building?
  • Were blinds required, and if so, where?

Following the completion of our thermal model, we were able to send feedback that, in line with TM52 and the employer’s requirements, there was no overheating risk within the building. This enabled the removal of the solar shading from the building, in line with these CIBSE standards. Galliford Try was able to exclude this provision from their design, and reinvest the capital saved on this feature of the project elsewhere. 

Galliford Try said about this experience: “Whenever we work with anyone from the Darren Evans Team, we know that they will deliver on their promises”.  

If this kind of thermal modelling might be useful to your project, our  very experienced team of domestic, commercial and BREEAM assessors would be delighted to hear about how we can help. 

Get in touch:

Our BREEAM Assessors are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

 

 

There are many residential projects that include great energy efficient junction detailing, however SAP Calculations usually does not benefit from this energy efficiency. Many projects choose to apply generic nominal thermal junction heat loss values (accredited Construction Details) rather than accurately model the specific heat lost through project thermal junctions. This leads to an increased pressure and over specification of ground floor, walls, roof and window U Values. This need not be the case. By modelling the specific energy efficiency performance of thermal junctions an accurate representation of the heat lost through these linear lengths can be achieved. This permits a reduction in specification in both building fabric as well as fixed building services.

Whilst working with Galliford try on a new residential development comprising 3, 4 & 5 bedroom homes we discussed the benefit of modelling certain psi values to more accurately describe the energy efficiency standards to which these junctions had been designed. Through collaborating together we identified a suite of 4 psi values to calculate and use across the site of 210 units. The design of the thermal junctions enabled us to achieve great psi value results

Junction Name

SAP Ref

Comments

ACD

Results

% reduction

Window Sill

E3

2D

0.04

0.004

90%

Window Jamb

E4

2D

0.05

0.006

88%

Gable

E12

2D

0.24

0.103

57%

Corner

E16

2D

0.09

0.057

37%

These 4 psi value results achieve an average improvement over Accredited Construction Detail (ACD) values of 68%. This performance enabled Part L calculations to comply easily with both TFEE & TER Part L thresholds without a need to over specify in project U Values or increase specification from fixed building services. Modelling these thermal junctions ensured that the energy efficient design on the project was incorporated to its fullest and was not wasted through the application of generic (less energy efficient values).

Given the number of units on the site, the cost of each junction was £1.19 per plot. This cost efficiency will further reduce as these details can be used on future projects where these details are employed again.

If we are consulted on the performance of your thermal junctions early enough we can also provide guidance as to how to further improve a junctions energy efficiency. 

Simon from Galliford Try said the following about the service that we provided “Working with Darren Evans to identify and develop psi values for critical junctions has delivered significant benefits to SAP and our financial model. These have been a huge benefit and one that is to be repeated on new projects. Their technical expertise has assisted us to maintain a fabric first approach to compliance with ADL1a”.

Working to support the construction industry to achieve a more energy efficient housing stock is something that we are passionate about.

Get in touch:

Our BREEAM Assessors are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

Rollalong Ltd are specialists in permanent offsite construction who contacted us via our website with an interest in learning more about whether calculating project specific psi values might better represent  their construction method in a residential project they were working on. As always we took the time to discuss the project in detail with them so that we fully understand what they were trying to achieve. Following our discussion we were commissioned to calculate a suite of 15 psi values for a light steel frame residential project requiring both 2D and 3D modelling. All we needed to get started was a set of dwg drawings from which to model the junctions. We completed an initial set of calculations within the timeframe agreed with Rollalong and issued our calculations for review and comment. Following on site changes in materials we were instructed to make alterations and issue a revised set of calculations which achieved the following results

 

Junction Name

SAP Ref

Comments

Default

Results

% reduction

Window Head

E2

3D 

1

0.017

98%

Window Sill

E3

3D

0.08

0.023

71%

Window Jamb

E4

2D

0.1

0.053

47%

Ground Floor Sidewall

E5

3D

0.32

0.096

70%

Ground Floor Endwall

E5

3D

0.32

0.104

68%

Exposed Floor (Normal)

E20

3D

0.32

0.135

58%

Exposed Floor (inverted)

E21

3D

0.32

0.158

51%

Intermediate Floor between Dwellings Sidewall

E7

3D

0.14

0.049

65%

Balcony

E23

3D

1

0.219

78%

Flat Roof to Parapet

E15

3D

0.56

0.148

74%

Corner

E16

2D

0.18

0.066

63%

Party Wall between Dwellings

E18

2D

0.12

0.033

73%

Staggered party wall

E25

2D

0.12

0.024

80%

 

These results achieve an average improvement over default Appendix K junction heat loss values of 69%. This performance enabled Part L calculations to comply easily with the TFEE without any additional over specification and cost in the U Values in the floor, walls, roof or windows across this project. It also permitted the dwellings to work to a more realistic air test result i.e. 5.00.

Often projects over engineer the fabric performance of floors, walls, roof and windows to compensate for a poor representation of heat loss through the thermal junctions, however, this was not the case on this project.

Adam from Rollalong doors said the following about the service that we provided “My overall experience from Darren Evans has been very positive, when we approached Darren Evans to provide us with thermal bridging calculations, we were on a very tight timescale due to project constraints. These Targets were exceeded and information delivered 1 week early which was good for overall design target dates. The team I dealt with were very professional and worked well, communicating during the task and process. In terms of monitory costings Darren Evans was not the cheapest but also not the most expensive company we were quoted by. But I felt that the manner in which the initial communications were handled and information provided gave me confidence in the competency of the company. We have just engaged with another enquiry with Darren Evans to be completed in the new year”

Working to support the construction industry to achieve a more energy efficient housing stock is something that we are passionate about.

Get in touch:

Our BREEAM Assessors are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

Galliford Try approached us, wanting to ensure that a residential development they were constructing with non-residential communal spaces did not pose a risk of overheating to future residents. Solar glazing control had already been incorporated into the fenestration strategy, to mitigate the risk of the development overheating; however, the company also wanted to run a calculation in line with CIBSE TM52 and TM59, to ensure that both residential and non-residential parts of the building had been suitably protected from a solar gain.

Following some collaboration with Galliford Try, we came up with an innovative approach: an elevation-specific glazing specification. This would ensure that elevations at risk of overheating would have an appropriate level of solar control, and elevations not at risk of excessive solar gain could utilise a more relaxed glazing specification to encourage heat gains.
This elevation-specific solar glazing approach brought the following benefits to the building design:

  1. Elevations with a potential high solar gain would not end up overheated, with uncomfortable internal temperatures.
  2. For elevations where overheating was not an issue, solar gain was encouraged.

By approaching solar gain individually for different elevations, the building has been designed to function more energy efficiently, and Galliford Try have been able to avoid over-specifying solar shading in the building’s fenestration strategy.

According to Galliford Try: Darren Evans have played a significant part in the success of this business unit in the south west.

We have a team of domestic, commercial and BREEAM assessors with years of collective experience, and we’d love to hear about how we could help with your project.

Get in touch:

Our BREEAM Assessors are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

The Devon’s Road redevelopment project is located on the former Bow Industrial Park, and has been built over three phases and when finished in 2019 will provide a total of 384 new homes, 10 new commercial units, as well as community play areas. Darren Evans Assessments has worked closely with Galliford Try for the last 10 years and we have collaborated with Galliford Try on the energy assessment and sustainability compliance aspects of this development in relation to both residential and commercial aspects since 2013. 

One of the overarching services that we have provided for the scheme as it has developed has been acting in the role of BREEAM assessor. We have assessed all the new commercial development that has been completed over the 3 phases providing the following BREEAM related services:

  • BREEAM assessor for both 2011 and 2014 regulations
  • BREEAM Accredited professional
  • Ecology support and advice
  • SAP Calculations for the residential elements of the project
  • SBEM Calculations for the new commercial units
  • IMPACT assessment to measure & reduce the buildings environmental impact
  • Thermal Modelling to CIBSE Guide TM52 & TM59
  • Green Lease Agreement 
  • Low Zero Carbon Report advising on the suitability of renewable technologies on site
  • Energy and sustainability Reports to sign off planning and sustainability criteria

Throughout the project we have remained up to date and informed as Part L and BREEAM regulations have changed to ensure that we are providing correct and relevant guidance. We have worked closely with all members of a shifting design team across all 3 phases to coordinate the receipt of required technical specifications in line with the BRE’s requirements incorporating leading design team meetings and site inspections. We have been able to advise on required alterations to the renewable and site wide heating and hot water provision to ensure provision is suitable for the needs of the residential and commercial property on site as well as in line with planning requirements. 

Matthew from Galliford Try said the following about the service that we provided “Having worked with Darren Evans over the last 4 years I can only say positive things about them, they are helpful, provide professional tailored reports in a timely manner and offer great support to our construction site teams.” 

We have a very experienced team of domestic, commercial and BREEAM assessors and we would be happy to hear about your project and how we can help.

Get in touch:

Our BREEAM Assessors are here to answer any of your queries, or if you would like a FREE quotation, please give us a call on 0333 5777 577 or fill in our contact form and we will get back to you.

 

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