Andrée Dargan, County Architect with Dun Laoghaire on their experience of carrying out deep retrofit of their social housing stock. Presentation given at SEAI's Deep Retrofit conference on 21st June 2017

1. Towards Zero
National Deep Retrofit Conference
Aviva Stadium
21 June 2017
The Dún Laoghaire-Rathdown Experience
Rochestown House, EuroPHit Deep Refurbishment Pilot Project
Andrée Dargan, DLR County Architect

2. Retrofitting Social Housing in DLR - Preamble
• EuroPHit Demonstration Site – Rochestown House
• Project Overview
• Build Process
• Energy Analysis
• Lessons Learned
Public Sector and LA Role

3. EuroPHit – Rochestown House
Retrofitting Social Housing in DLR – Pilot Project

4. Rochestown House, Phase 2 – EuroPHit EU Pilot Project,
A passive house upgrade of existing Housing for the Elderly
Dramatically Improving the Energy Performance and
Comfort of Existing Buildings with Step-by-Step
Refurbishment and Integration of Renewable Energy Systems (EUROPHIT )
Retrofitting Social Housing in DLR – Pilot Project
EuroPHit - Rochestown House

5. Rochestown House, Phase 2 – EuroPHit EU Pilot Project,
A passive house upgrade of existing Housing for the Elderly
Dramatically Improving the Energy Performance and
Comfort of Existing Buildings with Step-by-Step
Refurbishment and Integration of Renewable Energy Systems (EUROPHIT )
Training for design team
Training for tendering contractors
Further training for successful contractor
Supervision on site
Education on site – study trips
Monitoring and Verification
Post Project Analysis
Supported by DHPCLG & SEAI through BEC 2014
Retrofitting Social Housing in DLR – Pilot Project
EuroPHit - Rochestown House

6. • Located within the former walled garden
of an estate house near local shops and
amenities in Sallynoggin
• Existing small Bedsits were too small and
difficult to rent - dark, cold, damp
• Creating a new community of smart and
accessible buildings
• Long term living - range of unit types to
suit evolving needs
• Part of DLR downsizing project
• Multi Stakeholder - DLR, Local
Community, DHPCLG, SEAI, EuroPHit
COMMUNITY
Retrofitting Social Housing in DLR – Project Overview
Setting

7. PHASE 1
PHASE 2
PHASE 3
• The Site is being upgraded in three
phases – phases 1 and 2 complete,
phase 3 on site.
• Phase 2 - EuroPHit Deep
Refurbishment to EnerPHit Passive
House refurbishment standard
Retrofitting Social Housing in DLR – Project Overview
Site Layout

8. Retrofitting Social Housing in DLR – Project Overview
Phasing
PHASE 1 PHASE 1

9. Phase 1 – 18 bedsits upgraded to 12 one bed units
• Deep retrofit
• External insulation
• Demand control ventilation
• Upgrade of district heating from oil to gas
• From F/G BER to B2/C1 BER
Before upgrade
Finished project after upgrade
Retrofitting Social Housing in DLR – Project Overview
Phasing

10. PHASE 2
Retrofitting Social Housing in DLR – Project Overview
Phasing
PHASE 2

11. Phase 2 – 26 bedsits and 8 one bed apartments
upgraded to 34 one bed units
• Accessible/Ambulant with lift added
• Facilities – office, nurse’s station, laundry,
commercial kitchen, communal room
• Project cost c.€3.5m
• Energy efficiency elements c.€890k
Unit size before upgrade - 24m2 Unit size after upgrade - 48m2 Before upgrade
Retrofitting Social Housing in DLR – Project Overview
Phasing

12. Phase 2
• EnerPHit - PH refurbishment standard
• Upgrade of district heating from oil to gas micro
CHP serving Phases 2 and 3
• Airtightness below 1 air change per hour
• Heat recovery
• From F/G BER to A3/B2 BER
Unit size before upgrade - 24m2 Unit size after upgrade - 48m2 Before upgrade
Retrofitting Social Housing in DLR – Project Overview
Phasing

13. PHASE 3
Retrofitting Social Housing in DLR – Project Overview
Phasing
PHASE 3

14. Phase 3 - 14 new units
12 x 1 bed (58m2) and 2 x 2 bed (75m2)
8 will be wheelchair accessible, 6 will be ambulant accessible
• To Passive House standard
• Use of district heating from gas micro CHP in Phase 2
• Airtightness below 0.6 air change per hour
• Heat recovery
• Predicted A2 BER, nZEB compliant
Retrofitting Social Housing in DLR – Project Overview
Phasing

15. Single storey units Two storey blocks
Retrofitting Social Housing in DLR – Project Overview
Phasing

16. Construction Commenced November 2014
Completion Date August 2016
Retrofitting Social Housing in DLR – Rochestown House, Phase 2

17. Northwest view
Northeast view
Built during the early 1970’s
Floor, internal walls and roof - poured concrete
with little or no insulation incorporated
External walls - concrete panels with pebble
dash finish
Solar gains with heavy shading to the northwest
and quite open to the southeast
Plant room on the roof accommodating a low
efficiency oil-fired boiler
Retrofitting Social Housing in DLR – Building - Before
Existing Fabric

18. Relatively low floor to ceiling height
Ventilation mostly natural, using opening window sections and room-based fans
Retrofitting Social Housing in DLR – Building - Before
Existing Fabric
Internal views of existing communal area on the first floor

19. Interof Communal area on first floor
Retrofitting Social Housing in DLR – Building - Before
Existing Fabric

20. Retrofitting Social Housing in DLR – Energy Analysis - Before
Existing Fabric in PHPP
• Cost to heat this building
to 20ºC 24/7/365 would
be c.€53,000 per year
• Annual heating demand
410 kWh (m2a)

21. Ground Floor Plan
First Floor Plan
Second Floor Plan
Cross Section
• Additional lift and stair core
• New floor added on top of
existing
• New communal areas and
facilities
• New mini CHP and heat
recovery ventilation system
• Whole building externally
insulated
Retrofitting Social Housing in DLR – Construction - Proposal
Design Solution

22. Front Facade (Northwest)
Back Facade (Southeast)
Retrofitting Social Housing in DLR – Construction - Proposal
Design Solution

23. Existing concrete
wall panels:
‘U’Value
3.75 W/m²K
Externally
insulated with
200mm EPS
‘U’Value proposed
0.15 W/m²K
Existing wall
panels:
Externally
insulated with
250mm EPS
‘U’Value proposed
0.12 W/m²K
BACK FACADE
South East
New wall:
215mm aerated
block externally
insulated with
200mm EPS
‘U’Value:
0.13 W/m²K
FRONT FACADE
North West
New wall:
215mm aerated
block with
150mm EPS
‘U’Value:
0.16 W/m²K
Existing Floor:
150 mm concrete floor
‘U’Value 4.30 W/m²K
New Roof:
Insulated metal deck with
50mm sound insulation
150mm PIR insulation
‘U’Value:
0.13 W/m²K
Retrofitting Social Housing in DLR – Construction - Proposal
Specification

24. Retrofitting Social Housing in DLR – Construction - During
Wall Buildup

25. Retrofitting Social Housing in DLR – Construction - During
Roof Build-up

26. Retrofitting Social Housing in DLR – Construction - During
Fire Stopping

27. Recessed
Flush
Retrofitting Social Housing in DLR – Construction - During
Window Positioning

28. Retrofitting Social Housing in DLR – Construction - During
Recessed Window Detail

29. Window Cill detail in Therm
Retrofitting Social Housing in DLR – Construction - During
Recessed Window Detail

30. Window Cill detail
Main Contractor Proposal
Retrofitting Social Housing in DLR – Construction - During
Recessed Window Detail

31. Window Cill detail in Therm
Main Contractor Proposal
45% better!
Retrofitting Social Housing in DLR – Construction - During
Recessed Window Detail

32. Retrofitting Social Housing in DLR – Construction - During
Recessed Window Detail

33. Ψ Value = Ψ Value =
Steel angle
causing a massive
thermal bridge
(standard detail)
Steel angle
25mm set back
from the edge of
the insulation layer
(tender detail)
Retrofitting Social Housing in DLR – Construction - During
Flush Window Detail

34. . . . as per tender
drawings
Glazed Door Position . . .
. . . as required by door
manufacturer
. . . as required by door
manufacturer with 20mm
of insulation overlap.
Retrofitting Social Housing in DLR – Construction - During
Door Head Detail

35. . . . as per tender
drawings
Glazed Door Position . . .
. . . as required by door
manufacturer
. . . as required by door
manufacturer with 20mm
of insulation overlap
Psi value = 0.030 W/mK Psi value = 0.441 W/mK Psi value = 0.387 W/mK
Retrofitting Social Housing in DLR – Construction - During
Door Head Detail

36. at construction stage
at tender stage
Retrofitting Social Housing in DLR – Construction - During
Existing Foundation Detail

37. Internal Surface Temperature
>15 ºC
Minimum required height from top of foundation to top of floor slab: 290 mm
To insure that at skirting level the surface temperature is above 15 ºC
Retrofitting Social Housing in DLR – Construction - During
Existing Foundation Detail

38. In below / In above Out below / In above Out below / Out above
Retrofitting Social Housing in DLR – Construction - During
Airtight Line Decisions

39. Retrofitting Social Housing in DLR – Construction - During
Airtight Challenges

40. Retrofitting Social Housing in DLR – Construction - During
Airtight Taping

41. Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey

42. Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey

43. 1st Option:
Decentralised system
Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey
Advantages:
High overall HRV efficiency
Reduced duct nominal width
Disadvantages:
High capital cost
High maintenance level

44. 2nd Option:
Centralised system
Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey
Advantages:
Low capital cost
Low maintenance level
Disadvantages:
Low HRV efficiency
Increase duct nominal width
Fire dampers required (cost)
Parapet height increased
Load bearing structure (cost)

45. 3rd Option:
4 Centralised units
Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey
Advantages:
Low capital cost
Low maintenance level
Disadvantages:
Low HRV efficiency
Increase duct nominal width
Fire dampers required (cost)
Parapet height increased
Load bearing structure (cost)

46. Back to 1st Option
Decentralised system agreed
Retrofitting Social Housing in DLR – Construction - During
Ventilation Journey

47. Retrofitting Social Housing in DLR – Construction - During
Ventilation

48. Micro CHP
Gas Boilers First Floor Plant
Retrofitting Social Housing in DLR – Construction - During
District Heating

49. Heat Recovery Ventilation
(Communal room unit)
User controls
Retrofitting Social Housing in DLR – Construction - During
MHRV

50. BCMS System with remote access
BCMS
Retrofitting Social Housing in DLR – Energy Analysis - After

51. BCMS
Retrofitting Social Housing in DLR – Energy Analysis - After
Energy
Consumption
per Floor for
February 2017

52. Retrofitting Social Housing in DLR – Energy Analysis - After
BCMS

53. Retrofitting Social Housing in DLR – Energy Analysis - After
BCMS

54. • To heat this building to 20ºC
24/7/365 a reduction of 80%
in cost anticipated
• Annual heating demand
25 kWh (m2a)
Retrofitting Social Housing in DLR – Energy Analysis - After
Results of Upgrade in PHPP
.8

55. Before Retrofit
Annual heating demand 410 kWh (m2a)
After Retrofit
Annual heating demand 25 kWh (m2a)
Retrofitting Social Housing in DLR – Energy Analysis - After
Heating Energy Balance

56. Retrofitting Social Housing in DLR – Energy Analysis - After
• EnerPHit Certification process underway
• BER
Ground Floor B2
Middle Floor A3
Top Floor A3 (new build)
Certification

57. • Illustrates how existing stock can be reused even if it is in poor condition
• Greater awareness of the importance of Energy by Client and Tenants
• nZEB & PH - high standards with emphasis on on-site care and quality assurance,
required to ensure effective on-site attention to detail
• National up-skilling of the design and construction sectors is needed for either build
• Positive but huge learning experience for both Contractor and Design team
• Passive Consultant and Architects’ Department learned as the project developed -
Theory v Practice - be alert to impact on project costs
• Significant knowledge dissemination
Retrofitting Social Housing in DLR – Lessons Learned
General

58. - At design stage carry out an air leakage search
A way to learn more about the existing fabric
- At tender stage specify in detail each transparent component
G values, Uf values for each frame/glass type
- Programme in preliminary pressurisation tests for the entire building
Contractor to price for temporary seals for this preliminary tests
- Select Main Contractor with training and experience in PH / low energy construction
It will save hours of discussions (time is money)
- When selecting windows/doors check if construction fitting detail is acceptable from
the manufacturer point of view
Structure and weather future proof
- On site supervision
It’s crucial
Retrofitting Social Housing in DLR – Lessons Learned
Construction

59. EU / National
• EU policy
• National commitments
• Funding
• EuroPHit project
• Industry learning
Client
• Downsizing policy
• Quality housing stock
• Template for future refurbishments
• Less ongoing maintenance
• Smart building
• Development of new community
Tenant
• Part of new community
• Healthy
• Comfortable
• Economic
• Shared facilities
Interchangability
Replicability
Scalability
Retrofitting Social Housing in DLR – Rochestown House
Benefits of Project

60. • Sustainability - Social, Economic, Environmental
• Benefits to be achieved by designing an energy efficient
but also smart building have a huge impact
• Building should be smart (back of house) but must be user
friendly (front of house)
• Need post occupancy review to ensure expected
outcomes have been achieved
• Energy upgrade project has enabled Council's desired
downsizing policy to be kick-started, other projects now
underway
• 90% of existing building stock will still be in use in 2050,
Government's Housing Action Plan puts emphasis on
making best use of existing stock
• Funding implications for deep retrofit
• Policy does affect change but you need a led vision
• Benefit of pilot projects
• Construction employment opportunities
• New learning and standards
Retrofitting Social Housing in DLR – Rochestown House
Conclusions

61. Client – DLR Housing Department
Design Team
• Architects – DLR Architects’ Department
• Civil & Structural Engineers – Hanley Pepper & Assoc
• Mech & Elec Engineers – Ramsay Cox & Assoc
• Quantity Surveyors – Walsh Associates
• Passive House Consultants – MosArt
• PSDP – Scott & McNeill
Contractor
• Main Contractor - Manley Construction
• Mech Subcontactor - MPH Ltd
• Elec Subcontractor - D & N Group
• Airtightness - Advanced Airtight Solutions Ltd
Retrofitting Social Housing in DLR – Rochestown House

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69. Retrofitting Social Housing in DLR – Rochestown House

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72. Retrofitting Social Housing in DLR – Rochestown House

73. Hair Dressers Communal LaundryMain StairsCorridor
Apartment Type A
Retrofitting Social Housing in DLR – Rochestown House
Apartment Type B

74. Retrofitting Social Housing in DLR – Rochestown House

75. Thank you
adargan@dlrcoco.ie
21 June 2017
Retrofitting Social Housing in DLR – Rochestown House

76. Retrofitting Social Housing in DLR – Rochestown House