Implications of nZEB Retrofit on Fuel Poverty. Technical obstacles, governance issues. Need for a holistic approach to assessing cost optimality, need for thermal bridge calculation, sustainability measurement and a jaundiced view of the renewables requirement contained in the Irish national Dwelling Energy Assessment Procedure (DEAP) for retrofit. Many RES decisions are not sustained under lifecycle cost assessment.
2. Societal Needs
Minimum 80% carbon emissions reduction by 2050
40% of all emissions related to buildings
90% of all buildings standing will still be standing in 2050
90% of them need to be upgraded to a BER of A2 (nZEB)
Biggest construction project in human history
Who has the knowledge and skills to achieve this? – We
do.
3. DIT Experience in Retrofit
4 years of level 9 (Masters) in Retrofit Technology
Retrofit Residential, Commercial & Institutional to
nZEB
60 graduates in the marketplace
116 post-graduate professionals researching retrofit
Hosted 3 national nZEB conferences
Biggest database of nZEB research in Ireland
Shortlisted for SEAI research awards 2014
4. Overall Findings
insurmountable
We can do nZEB, there are no technical barriers
It is economic, it will pay for itself in time
It will work, nZEB can reduce emissions by at least
85%
It could eliminate fuel poverty permanently
We have no shortage of skills (at present)
Obstacle: Govt commitment to fund exemplars
obstacle
5. 2012 student project work
Postgraduate Certificate in Digital Analysis and Energy Retrofit
6. 2011 Gullwing project brief
Achieve a BER of A3
Achieve compliance
with Part L, 2011 (new
build)
Condensation risk
Surface temperatures
Calculated thermal
bridges
7. Digital Analysis of Existing Building
The apartments are:
Un-heatable (Part L)
Un-healthy (Parts L&F)
Un-visitable (Part M)
Un-comfortable
Non-compliant (Part B)
Too small (DECLG standards)
8. Simplify thermal envelope
33% improvement in
energy performance
coefficient
with no additional
insulation
Source: Team D - DT774
Simplifie
d
thermal
envelop
e
geometr
y
16. DCC Proposal 2010
WARNING!
Based on linear thermal
bridge default of 0.15
17. Insulate without LTB assessment?
Default y-factors allowable
are 0.15 and 0.08
depending on construction
quality
Calculated y-factors in the
Gullwing / Flat-Top blocks
ranged 0.32 to 0.36
DEAP defaults are
misleading!
18. Is DCC Proposal “Cost Optimal”?
The apartments are:
Un-heatable (Part L)
Un-healthy (Parts L&F)
Un-visitable (Part M)
Un-comfortable
Non-compliant (Part B)
Solved
?
Partly
No
No
No
No
No
Too small (DoE standards)
19. Flat-Top Block - project brief
Building Regs as if new build
DoE space standards
60-100 year lifecycle
BER of A2
Calculated y-factor
Hygrothermal analysis
Surface temperature
Condensation risk
20. Flat-Top Block
Results 95% Confidence Interval Uncertainty
Air flow at 50 Pa, V50
[m3/h] 1085 1060 1105 +/-2.0%
Air changes at 50 Pa, n50
[/h] 6.601 1.320 11.90 +/-80.0%
Permeability at 50 Pa, q50
[m3/h.m2] 5.255 1.050 9.461 +/-80.0%
Specific leakage at 50 Pa, w50
[m3/h.m2] 29.259 5.844 52.674 +/-80.0%
22. Digital energy analysis
BIM model Embodied Carbon
Therm Surface Temperature, Psi- values
BuildDesk Condensation risk, U-values
DEAP Energy balance, carbon emissions
23. Digital energy analysis
BIM model Embodied Carbon
Therm Surface Temperature, Psi- values
BuildDesk Condensation risk, U-values
DEAP Energy balance, carbon emissions
… I am competent
…
… reasonable skill care and diligence
…
I certify that … the design … is in
compliance … with Building
Regulations
24. DIT Proposal -“Cost Optimal”?
Solved
?
The buildings are:
Un-heatable (Part L)
Un-healthy (Parts L&F)
Un-visitable (Part M)
Un-comfortable
Non-compliant (Part B)
Too small (DECLG)
Yes
Yes
Yes
Yes
Yes
Yes
Green
Public
Procurement
30. DEAP focus on renewables adds costs
€14,000
Heat Pump –
Cost Optional
over 50 years?
€4,500
PV -
Cost Optional
over 10 years?
€14
Saving = €18,500
31. nZEB Retrofit Project Outcomes
BER of A2/A3
100% compliance as new build (Parts B, M, K & L)
Zero Surface Condensation
90% fuel cost reduction (€1,486 to €156)
100% Replicable
33. Why not?
Co-benefits need to be measured and added to the Retrofit
budget. This can only be done by committing to fund a
series of nZEB retrofit exAenmdp ala Mrsi.nister for Climate Change.
Social Economic
Fuel poverty
Employment
Skills
Health
Carbon saving/trading
Self-funding
Sustainable
Fuel imports
34. Follow me on twitter: @PassiveLogical
Simon McGuinness MRIAI, Dip.Arch., B.Arch.Sc., CEPHD
Notas do Editor
356 kWh/m2/y = €00572 x 73 = €1,486
49 kWh/m2/y = €00438 x 73 = €156