Risk mitigation strategies for retrofits

Update from:
Fiona Smith (Marketing and Communications Manager SEAI)
6th February 2019
1

Impact of NZEB on Domestic Retrofits - Major Renovation
www.seai.ie
2
What are the risks for homeowners and how are they avoided?
Best Practice Retrofit Case Study: Applying a Risk Management Process
PAS 2035 - A new UK standard for domestic retrofit
Risk Mitigation Strategies for Retrofitting Homes

Energy Performance in Buildings Directive
www.seai.ie
3
NZEB and Major Renovation
Going Forward
Implementation through Building Regulations
Impact of NZEB on Domestic Retrofits - Major Renovation
Orla Coyle, Programme Manager – Near Zero Energy Buildings & High
Performance Retrofit, SEAI

• Member states to ensure that all new buildings are “Nearly Zero Energy
Buildings” by 31st Dec 2020
• Member states to ensure that all new buildings owned and occupied by
Public Authorities are `Nearly Zero Energy Buildings’ after 31st Dec 2018
• Major Renovations to be at Cost Optimal Level in Building Codes .
Energy Performance of Buildings Directive

Energy Performance of Buildings Directive
Article 9 Nearly Zero Energy Buildings are defined as…..
“nearly zero-energy buildings” means a building that has a very high energy
performance, as determined in accordance with Annex I. The nearly zero or
very low amount of energy required should be covered to a very significant
extent by energy from renewable sources, including energy from renewable
sources produced on-site or nearby;”
Article 7 Major Renovations to be at Cost Optimal Level in Building Codes .
“more than 25% of the surface area of the building envelope undergoes
renovation”

Implementation through
Building Regulations

Domestic – New Buildings - NZEB
Durkan Homes – Citywest
25% Improvement on Current Regulations
Same Fabric Performance
- Boiler with Increased PV
- Boiler with MVHR and PV
- Heat Pump
MPEPC: 0.3
MPCPC: 0.35
RER: 20%

Comparison in Example Buildings
Parameter Part L 2011 Part L 2018
Gas Boiler
Part L 2018
Heat Pump
Wall U Value 0.13 W/m2K 0.13 W/m2K 0.13 W/m2K
Floor U Value 0.14 W/m2K 0.14 W/m2K 0.14 W/m2K
Roof U Value 0.11 W/m2K 0.11 W/m2K 0.11 W/m2K
Window U Value 1.3 W/m2K 0.9 W/m2K 0.9 W/m2K
Thermal Bridging 0.05 0.05 0.05
Air Permeability &
Natural Ventilation
Natural Ventilation with
Extract Fans
Extract Fans – AP: 5
m3/hr/m2 or
cMEV - AP: 3 m3/hr/m2
Extract Fans – AP: 5
m3/hr/m2 or
cMEV - AP: 3 m3/hr/m2
Secondary Heating Gas Fire 80% NA NA

Comparison in Example Buildings
Parameter Part L 2011 Part L 2018
Gas Boiler
Part L 2018
Heat Pump
Space Heating Boiler 91.3% Boiler 91.3% Heat Pump 350% Htg &
100% HW
Controls Time & Temperature Time & Temperature Time & Temperature
HW Flow Restrictor on Shower Flow Restrictor on Shower
Lighting 100% low energy 94 lumen/cW
4 W/m2
94 lumen/cW
4 W/m2
Photovoltaic 1.05 kWp 1.15 kWp 0
Primary Energy/ C02 56 kWh/m2 / 10 kgCO2/m2 43 kWh/m2 / 8 kgCO2/m2 39 kWh/m2 / 7.8 kgCO2/m2
EPC/ CPC 0.4 / 0.37 0.29 / 0.26 0.28 / 0.26
RER 0.18 0.24 0.38

Upgrade
- Fabric
- Heating & Controls
Domestic – Existing Buildings – Major Renovation
Deep Retrofit Supported Project
“more than 25% of the surface
area of the building envelope
undergoes renovation”

What works are included
Proposed Works to Elements
External Walls External Insulation of heat loss walls
Replacement or upgrade of external wall structure
Internal lining of the surface of heat loss walls
Window Renovation Replacement of Windows
Roof Renovation Replacement of Roof Structure
Floor Renovation Replacement of Floors
Extension Extension works which affect more than 25% of the surface
Where major renovation of walls, roofs and ground floors constitute essential repairs due to fire, storm or flood damage or damage as a result
of a material defect such as reactive pyrite it is not considered economically feasible to being these to cost optimal level
Painting, replastering, rendering, re-slating, re-tiling, cavity wall insulation and insulation of ceiling are not considered major renovation works.

Major Renovations – Domestic
Cost Optimal Works activated by Major Renovation
Major Renovation > 25% surface area1,2,3,5 Cost Optimal level as calculated in DEAP
(Paragraph 2.3.3 a. )
Works to bring dwelling to cost optimal level in so far as they
are technically, economically and functionally feasible
(Paragraph 2.3.3 b. )
External walls renovation
The cost optimal performance level to be achieved is 125
kWh/m2/yr.
Upgrade insulation at ceiling level where
U-values are greater than in Table 5
&
Oil or gas boiler replacement6 & controls upgrade where the oil
or gas boiler is more than 15 years old and efficiency less than
86%
&/or
Replacement of electric storage heating7 systems where more
than 15 years old and with heat retention not less than 45%
measured according to IS EN 60531.
External walls and windows renovation
External walls and roof renovation
External walls and floor renovation
New Extension affecting more than 25%
of the surface area of the existing
dwelling’s envelope (see 2.3.6)
The cost optimal performance level to be achieved is 125
kWh/m2/yr
Upgrade insulation at ceiling level where
U-values are greater than in Table 5
&
Oil or gas boiler replacement6 & controls upgrade where the oil
or gas boiler is more than 15 years old and efficiency less than
86%
&/or
Replacement of electric storage heating7 systems where more
than 15 years old and with heat retention not less than 45%
measured according to IS EN 60531
&
Upgrade insulation at wall level where U-values are greater
than in table 5.

Proposed Works to Elements Major Renovation Additional Works
A) Window Replacement (13% of
envelope)
No NA
B) EWI or IWI of walls (35% of envelope) Yes
Upgrade insulation at ceiling to
0.16 W/m2K or table 5
AND
Upgrade heating system and controls
OR
Achieve 125 kWh/m2/yr.
C) EWI or IWI of walls and windows
replacement (48% of envelope)
Yes
D) EWI or IWI of walls and replacement
of roof structure (61% of envelope)
Yes
E) EWI or IWI of walls and replacement
of floor (61% of envelope)
Yes
Semi Detached (126m2):
- Hollow Block wall,
- pitched roof with 50mm mineral wool insulation on the ceiling,
- double glazing with 6mm air gap and a U value of 2.8 W/m2K,
- 80% efficiency gas boiler installed with no controls
- Fuel Stove

Proposed Works to Elements Major Renovation Additional Works
A) Window Replacement (15% of
envelope)
No NA
B) EWI or IWI of walls (22% of envelope) No NA
C) EWI or IWI of walls and ceiling
insulation (53% of envelope)
No NA
D) EWI or IWI of walls and windows
replacement (37% of envelope)
Yes Upgrade insulation at ceiling to
0.16 W/m2K or table 5
AND
Upgrade heating system and controls
OR
Achieve 125 kWh/m2/yr.
E) EWI or IWI of walls and replacement
of roof structure (53% of envelope)
Yes
F) EWI or IWI of walls and replacement
of floor (53% of envelope)
Yes
Terraced house (96m2):
- solid wall,
- pitched roof with 50mm mineral wool insulation on the ceiling,
- double glazing with 12mm air gap and a U value of 2.8 W/m2K,
- 68% efficiency gas boiler installed with no controls

Revised EPBD
• Long Term Renovation Strategy - NZEB by 2050

Background: The Review
www.seai.ie
19
Introducing PAS 2035 : 2019
Next Steps
Improving Standards – What is PAS?
PAS 2035 - A New UK Standard for Domestic Retrofit
Kate Duffy, Senior Policy Advisor, Dept. for Business, Energy &
Industrial Strategy

SEAI Energy Show 2019
Background: The Review
In 2015 DECC and DCLG commissioned Dr Peter Bonfield
to undertake
“an Independent Review of Consumer Advice, Protection,
Standards and Enforcement for UK home energy efficiency
and renewable energy measures”.
Each Home Counts Review published December 2016.
During the review several hundred organisations were
engaged including:
• trade bodies
• installers
• energy providers
• standard bodies
• manufacturers
• consumer groups

Why was it needed?
• Impact of individual failures
– Homeowners – health, financial, comfort and emotional distress
– Business growth – lack of confidence = lack of large scale investment
– Carbon and fuel poverty targets
• Caused by systemic failures and race to the bottom on costs
– Procurement processes in which decisions are made on lowest cost not quality criteria
– Lack of qualified work force especially for more difficult measures
– Poor assessment and isolated design and specifications
• Still seeing high failure rates, although many changes already been introduced
have made great steps
– PAS standards
– Guarantees; for SWI and CWI in particular

Recommendations
• A Quality Mark against which all those engaged in design and installation of
energy efficiency and renewable energy measures will be assessed and
certified
• A Consumer Charter to set out the positive experience that the consumer can
expect under the quality mark including response times, financial protections
and access to redress procedures when things go wrong
• A Code of Conduct to set out clear requirements and guidance on how
companies behave, operate and report in order to be awarded and hold the
quality mark
• Technical Codes of Practice and Standards for the installation of home
renewable energy and energy efficiency measures so that the risk of poor-
quality installation is minimised
• Development of an Information Hub and Data Warehouse.

TrustMark Delivery and the Framework
TrustMark have taken on the delivery of the quality mark. They have developed
Framework Operating Requirements and supporting Code of Conduct and
Consumer Charter
The Trustmark Framework covers a
number of home improvement sectors
and provides the overarching
consumer protection expected from all
registered businesses.
If refers to the relevant standards for
these sectors – for energy efficiency
these are PAS.

Each Home Counts
Quality Mark
TrustMark Framework
Each Home Counts
Code of Conduct
Each Home Counts
Customer Charter
Each Home Counts
‘Code of Practice’
PAS 2035 Retrofitting Dwellings to Improve Energy Efficiency: Specification and Guidance
Existing BSI Standards
Including PAS 2030,
BS 5250, BS 7913, etc.
New BSI standards
Assessment, Air-Tightness +
Ventilation, Energy Advice,
Building Performance
Evaluation
Non-BSI Standards
Existing standards, e.g.
NIA/INCA/SWIGA, MCS, CIBSE
EHC and BSI Retrofit Standards

Improving Standards: What is PAS?
The Publicly Available Specification (PAS) standards are consultative documents
used to formalise best practice for a specific area or industry.
To support the introduction of the Energy Company Obligation (ECO) scheme in
2013, the government sponsored the development of PAS standards for energy
efficiency; standards have generally been updated every two years.
Current Standards:
PAS 2030:2017 “Improving the energy efficiency of existing buildings.
Specification for installation process, process management and service provision”
PAS 2031:2017 “Certification of energy efficiency measure (EEM) installation in
existing buildings”

Introducing PAS 2035 : 2019
Retrofitting Dwellings for Improved Energy Efficiency: Specification and
Guidance
• Application
– Can be used for any domestic retrofit project (not just ECO)
– Must be used in conjunction with PAS 2030: 2019
– Requires the use of many other framework standards (PAS 2030, BS
5250, BS 7913, MCS standards, etc.)
• Compliance
– Every retrofit project must have a Retrofit Coordinator
– Retrofit Coordinator is responsible for ensuring PAS 2035 compliance,
and for protecting the client’s interest and the public interest

PAS 2035 Overview
1. Risk assessment
– Based on pre-assessment (triage)
– Determines the Path (A-C) through the PAS
2. Required qualifications depend on assessed risk
– All projects must have a Retrofit Coordinator
– Professional qualification required for other roles
3. Design
– Requirements depend on the risk Path (A-C)
– Improvement option evaluation and medium term plans required (B, C)
– Additional requirements for traditionally constructed and protected buildings (C)
4. Ventilation
– Assess existing, upgrade if inadequate or will become inadequate on retrofit
5. Measures Interaction Matrix
– Used in risk assessment (inherent and combined risks)
– Identifies where retrofit design must consider interfaces
6. Monitoring and evaluation
– Confirms agreed outcomes, investigates discrepancies

PAS 2035 Risk Assessment
• Carried out by Retrofit Coordinator
– Based on pre-assessment (triage) data – doesn’t have to be onsite
– Before whole-dwelling and ventilation assessments
• Risk assessed as A, B or C
– Depending on five criteria
• Number of dwellings and measures, construction, built form
• High rise and protected historic buildings are always risk C
• Assessed risk determines required qualifications
– Retrofit Assessor | Retrofit Designer
• Assessed risk determines Path through the PAS
– Path A: Simple requirements
– Path B: More onerous requirements
– Path C: Much more onerous requirements

PAS 2035 Annex B: Risk Assessment Criteria
2 Average number of
measures per dwelling
3 Inherent technical risk
of highest risk measure
4 Highest risk
combination of measures
5 Construction and built
form of buildings
1 Number of dwelling to
be improved
Overall risk grade

PAS 2035 Whole-Dwelling Assessment
• The assessment must include appraisal or identification of the following:
– The dwelling’s heritage, architectural features, structure, construction and condition
and building services in sufficient detail to establish its suitability for improvement.
– Constraints imposed by the site, e.g. exposure, access, party walls, rights of light,
consideration of adjoining properties, etc.
– Constraints imposed by the local planning authority.
– Location and severity of any construction defects or structural defects or leaks, and of any
condensation or mould growth.
– Energy efficiency measures already installed or proposed.
– A measured survey to establish the overall dimensions of the heat loss envelope, the
dimensions of building elements and openings.
– The construction in sufficient detail to establish the U values and moisture properties of the
main building elements.
– The installed building services and controls.
– Occupancy assessment (number and any vulnerability of occupants)
– An estimate of annual fuel use, fuel cost and carbon dioxide emissions made from fuel bills
or by using SAP or PHPP.

PAS 2035 Annex C: Ventilation
Assessment
• Existing ventilation is inadequate if:
– Evidence of condensation or mould
– No working ventilation system present
– Ventilation present but incomplete (including air inlets)
– Good IEV or PSV but intended/potential Q50 < 5 m3/m2h
Upgrade
• If existing ventilation is inadequate then:
– If intended Q50 > 5 m3/m2h then IEV or PSV required
– If intended Q50 < 5 m3/m2h then MEV, MVHR or PIV required
– System capacity must be based on full occupancy
– Demand control required to ensure energy efficiency

PAS 2035 Design
• Irrespective of Path, all designs must:
– Provide for the outcomes agreed with the Client
– Be based on the whole-dwelling assessment
– Take account of the architectural and heritage context
– Take account of planning and building control requirements
– Allow for the management of moisture in the building
– Include construction details (corners, junctions and edges)
– Consider interfaces between fabric, systems and occupants
– Include a ventilation upgrade if required
– Specify testing, commissioning and handover requirements
– Specify required guarantees and warranties

PAS 2035 Design
The scope of the retrofit design depends on the Risk Path
• Path A allows
– Design of single-measure system improvements by specialists
• Subject to approval of the design by the Retrofit Coordinator
• Paths B and C also require
– An improvement option evaluation to determine the appropriate package of
measures for the dwelling(s)
• Based on a SAP or PHPP assessment
– A medium-term retrofit plan to identify and prioritise the improvements the dwelling
needs by 2050
• Even if they cannot all be implemented immediately
• Path C also requires
– Specialist expertise when traditionally constructed or protected buildings are to be
improved

Installation
• Installation must comply with PAS 2030: 2019 – the standards are linked
• The PAS 2030 Retrofit Installer must work to a design that is compliant with
PAS 2035
• PAS 2030 includes requirements for;
– Validating the design and preparing a method statement
– Qualification or competence of operatives
– Pre-installation building inspections
– The installation process (measure-specific requirements)
– Testing, commissioning and handover
– Provision of guarantees and warrantees
– Record keeping

PAS 2035 Monitoring and Evaluation
• Objectives
– To confirm that intended outcomes have been achieved
– To identify any unintended consequences
• Basic monitoring
– Applies to every project (questionnaire)
– Confirms outcomes and customer satisfaction
• Intermediate monitoring
– Investigates poor outcomes, unintended consequences
• Advanced monitoring
– Further investigation to understand and resolve discrepancies between predicted
and actual outcomes

Next Steps
• Transition period for ECO
– PAS 2030: 2019 and PAS 2035: 2019 published May 2019
– PAS 2031 (certification standard) published June 2019
– Six-month period for UKAS re-certification of CBs
– Twelve-month period for CBs to re-certify installers
– Training of Retrofit Coordinators during transition period
• Promotion of TrustMark
– The current plan is for TrustMark to be incorporated into ECO3
– The next priority is to encourage the uptake of Trustmark in other policies
• Local authorities, ALMOs, housing associations, private landlords, supply chain
and green finance pilots

Conclusion
• Promoting through use in ECO and BEIS funded supply chain pilots
• Mitigating risks that the supply chain will need to develop to meet new
standards by set a long 19 months transition period from publication
• Plan for the new PAS standards to be reviewed at the 2 year point as normal
to react to supply chain learnings
• Will add costs but analysis shows that ECO should remain within the
schemes cost envelope
• Important but other areas need addressing to help with the systemic failures
• Procurement practices should be reviewed
• Consumer understanding and confidence
• Financial investment - £8bn ready to go but historic lack of confidence

Thank you!

Reducing Risks
www.seai.ie
39
Compliance and Building Control
Appropriateness of Fabric Solutions
The Quality of Guidance
What are the risks for homeowners and how are they avoided?
Joseph Little, MRIAI, Assistant Head of School at Dublin School of Architecture,
TU Dublin

What’s the most risky
thing you’ll do today?
Reducing risks
Risks for homeowners and avoidance

It’s useful to talk about a landscape of risk.
When evaluating risk one isn’t looking for single numeric value or ‘black & white’ answer. Instead
one seeks a well-founded estimation of risk and its mitigation in a context of many unknowns.
Outputs: An example of a landscape of risk assessments
created for the World Economic Forum in 2017
Reducing risks
What’s crucial:
1. A long-term view;
2. Good guidance;
3. Professional support;
4. The right assessment
methods;
5. Appropriate caution;
6. Accuracy;
7. Carry through!

High accuracy,
low precision
High precision,
Low accuracy
Reducing risks
Are precision and accuracy the same thing?
• No: see diagrams.
• In many cases accuracy is obtainable, even when precision
is poor.
• Training is essential to achieve sufficient accuracy:
educational programmes are available.
Government can improve future precision of moisture risk
assessments by:
• Providing 5-7 regional climate files for computer-based
risk assessments.
• Paying for measurement of hygrothermal characteristics
of a selection of existing, common Irish building materials.
• Including risk assessments in expanded SR54.
• Fund research into systemic effects.
• Funding ongoing measurement of deep renovation case
studies.

Reducing risks
TGD L
Avoidance of
surface or inter-
stitial condensation
Signposts
For
specification
BS EN 13788 - 2012
Hygrothermal
performance of
building components
and building elements
– calc. methods
BS 5250 (2011) 2016
Code of practice for
control of
condensation in
buildings BS EN 15026 - 2007
Hygro perf. of
building components
— Assess. of moisture
transfer by numerical
simulation
Prescriptive
A suite of moisture risk
assessment pathways
Simplified risk assessment
Full risk assessment
Air-dominated
Prescriptive, supported if
necessary by
computational fluid
dynamic simulation (CFD)
Specific guidance in
Approved Docs, CoP,
standards and trusted
sources (i.e. ASHRAE, CIBSE)

Moisture: The physical problem
Moisture causes 70 – 80 % of all building failures (worldwide)
Failures and problems may be changing and increasing (due to increased airtightness and insulation, fuel poverty,
overcrowding and changing uses).
Many factors and their possible interactions are still uncertain.
In particular, there is as yet insufficient knowledge of complex inter-relationships (energy efficiency, airtightness, indoor air
quality and human health).
Moisture: The inadequate guidance
The current approach is based predominantly upon the idea of a building as composed of discrete building elements in
perfect conditions, not affected by their interactions or context or use.
Moisture: A new approach needed
In reality, however, most building elements interact in multiple and sometimes complex ways
Building materials are also affected by changes over time.
The failure of current approach has led to significant moisture risks.
A new approach is therefore required.
Excerpts from Sanders & May (2016) Moisture in Buildings – An
integrated approach to risk assessment & guidance, Bsi, UK
The quality of guidance

Existing guidance based on buildings as discreet units
Sanders et al. (2011, 2016) Code of Practice
for Control of Condensation in Buildings
Energy Saving Trust (2003) CE17 - Energy Efficiency Best
Practice in Housing – Internal Wall Insulation in Existing
Housing

Excerpts from Sanders & May (2016) Moisture in Buildings – An
integrated approach to risk assessment & guidance, Bsi, UK
System & moisture-focused guidance

In recent years big increase in great
resources from UK bodies for
historic buildings: STBA, Historic
England, Historic Scotland, SPAB
guidance, & case studies
Sanders & May (2017)
Moisture in Buildings
(STBA, 2015) Planning
Responsible Retrofit
(STBA, 2015) Responsible
Retrofit Knowledge Centre
(STBA, 2017) A Bristolian’s
Guide to Solid Wall
Insulation
System & moisture-focused guidance
(Hist Scot, 2015) Technical paper 15: Assessing
risks in insulation retrofits using hygrothermal
software tools - Heat and moisture transport
in internally insulated stone walls

… But what was most remarkable about this ECO meeting was that the contractors and the
manufacturers of insulation materials were demanding not less ‘red tape’ but more ‘red
tape’. They are saying we want much higher standards set. We want compliance to be
enforced.
In fact one of the guys - that in my opinion was from one of the most irresponsible
companies - was saying “we want one in four buildings inspected on this programme.
Because the standard is SO low that we have to put in some clear compliance regulations.
Government has to act as Government”.
Industry wants the bar to be raised in regulation, so that they can raise their standards and
win work which rewards companies who do better work, not those who cut their costs most.
Neil May (RIP) – talking about UK’s ECO refurbishment scheme
at Retrofit Live conference organised by Core
(Centre for Refurbishment Excellence) in the UK, June 2015
Compliance & building control

Compliance & building control
7 m3/m2.hr to comply
with guided value in
TGD-L:2011 for new
build
5 m3/m2.hr to comply
with guided value in
TGD-F:2007 to avoid
40% increase in
background ventilation
7
5
Could the statistically significant grouping at key compliance thresholds indicate ‘gaming’ of the system, and possibly non-compliance?
Data on housing within
Dublin City Council
from SEAI National BER
Research Tool: Built to
Last Research Project

Specification & workmanship
Images of poor airtightness in a historic dwelling on Brighton Road.
Extracted from Built to Last Research Project

High indoor relative humidity
Can be caused by a combination of:
• High moisture production;
• Defective moisture extraction;
• Cool temperatures;
Indoor conditions logged in adjacent terraced houses in
Cabra, Dublin. Neighbours have higher occupancy but
also wall insulation & demand control ventilation on
both floors.
Extracted from Built to Last Research Project
Ventilation, IAQ & surface condensation

Ventilation, IAQ & surface condensation
On Oct 23, 2017 the Strasbourg-based
European Committee of Social Rights
(ECSR) found that the human rights of
local-authority tenants in Ireland have
been breached by local authorities’ failure
to provide adequate, clean and safe
housing…
…“No complete statistics on the condition
of local authority housing have been
collected since 2002 by the Irish
authorities and that in Ireland no national
timetable exists for the refurbishment of
local authority housing stock”.
A report I created on surface condensation
risks, responsibilities & alleviation was
submitted as an item of evidence. I have
brought some copies.

Traditional Non-traditional
Appropriateness of fabric solutions: Solid wall IWI

Mechanisms of heat and moisture transport
conduction
convection
radiation
vapour diffusion
vapour convection
capillary action
surface diffusion
Heat transport
Moisture transport

“The predominant moisture transport
mechanism in capillary porous materials
is the capillary liquid transport.”
Fraunhofer IBP
Moisture transport mechanisms
capillary
transport
vapour
convection
vapour
diffusion
The quantities of moisture involved
can be very different:
“If present, liquid transport may dominate
vapour diffusion by some orders of magnitude.”
Künzel & Karagiozis (2010)

Moisture absorptivity is easy to measure!
Use Karsten Tubes to gain a great sense of the
vulnerability of a solid wall.
(See Appendix 2 of HS Tech. Paper 15 for guidance)

Wall-floor assemblies considered
(a) Original condition (suspended floor)
(b) Existing condition (tanking & DPMs)
(c) Mainstream retrofit
(d) Proposed vapour permeable retrofit
Moisture risk assessment carried out
using WUFI 2D software application
from Fraunhofer IBP
Little, Arregi (2016)
Hygrothermal Risk Evaluation
for the Retrofit of a Typical
Solid-walled Dwelling

original condition existing condition
during driving
rain event
during drying-out
process
during driest
period
capillary
zone
Relative humidity distribution

mainstream retrofit proposed retrofit
during driving
rain event
during drying-out
process
during driest
period
Little, Arregi (2016) Hygrothermal Risk
Evaluation for the Retrofit of a Typical Solid-
walled Dwelling
“a mainstream approach appears to increase
hygrothermal risks to historic solid dwellings.
There is a need for parametric modelling to
expand this assessment to a range of wall and
ground assemblies, insulants and locations:
ideally, this would be supported by selected
physical testing.”
Relative humidity distribution
https://arrow.dit.ie/sdar/vol4/iss1/3/

Little, Ferraro, Arregi (2015) Technical paper 15:
Assessing risks in insulation retrofits using
hygrothermal software tools - Heat & moisture
transport in internally insulated stone walls

Cellulose
(blown, dried, shaved)
0.5, 0.25 W/m2K
Cellulose
(blown & membrane)
variable 0.5, 0.25
fixed 0.5, 0.25
Stone B exposed Stone A exposed Stone A rendered
80%RH
80%RH
U = 0.5 & 0.25 w.
Intello acceptable here
U = 0.5 & 0.25 may be
acceptable here
U = 0.5 may be
acceptable here
Risk too high
Risk too high
Risk too high

Calcium silicate
(fully bonded, lime
adhesive & plaster)
0.5 W/m2K
Phenolic foam
(insulated plasterboard,
fixed on rail)
No foil 0.5, 0.25
foil 0.5, 0.25
Stone B exposed Stone A exposed Stone A rendered
80%RH
80%RH
Acceptable
Only U = 0.5 w/o foil
acceptable for this wall
Risk too high
Risk too high
AcceptableProbably acceptable

Appropriateness of fabric solutions selected
Upgrading old insulated plasterboard pitched
roof insulation, with spotting due to thermal
bridges at simple metal fixings
Plan detail showing thermal
upgrade with low TB fixings
spotting due to thermal
bridges at simple metal fixings

Appropriateness of fabric solutions selected
Use of 2 layers of aerogel quilt
(green material) ensures
• Gutters need only adjust
marginally;
• Significant increase in wall
temperature & reduction in
condensation risk
Flat roof U = 0.10
warm pitched roof U = 0.13
wall U = 0.27 W/m2.K
ψ = 0.82 W/mK.
fRsi = 0.68 < 0.75
ψ = 0.29 W/mK
fRsi = 0.86 > 0.75

Risks can be assessed & measures taken to lessen, if not remove risks:
• The first thing is acknowledging that heightened risks exist, & require
an integrated response, caution & follow through!
• Some of risks are imposed by the low level of research by Irish
Government, Colleges and Industry, especially in relation to systemic
issues & new high performance requirements;
• Some risks indicate needs for education & awareness raising for
homeowners / occupants;
• Others can be mitigated by focused, technical upskilling of building
design professionals and construction workers.
Education for building design professionals
Awareness raising for homeowners

Postgraduate Certificate in Building
Performance (Energy Efficient Design)
Six key skills:
1. nZEB Policy & Technologies
2. nZEB Calculation & Cost Optimality
3. Energy Modelling Tools #1 (DEAP)
4. Energy Modelling Tools #2 (PHPP)
5. Hygrothermal Risk Assessment for
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Awareness raising for homeowners

Project Overview
www.seai.ie
69
Key Roles and Responsibilities
The Importance of Good Communication
A Design Team Approach
Best Practice Retrofit Case Study: Applying a Risk Management Process
Noel Rowland, Managing Director, Churchfield Home Services

Project Overview
Case Study – Deep Retrofit
70
Detached two storey house
built 1940, with rear
extension built 1985.
Hollow block walls with
external render and pitched
roof.
Works were completed as
part of the Deep Retrofit
Pilot Project in 2018
Featured on RTE Eco Eye in
January 2019

Project Overview
71

Design Challenge
- Achieve an overall BER of A3 or higher
- A minimum BER uplift of 150 kWh/m2/yr
- Minimum heat loss factor of 2.0 W/m2K in the BER to be achieved
- Reduce air leakage to less than 5m3/h/m2 @50 pa or lower
- Ensuring adequate air quality by incorporating a whole house mechanical ventilation
system
- Minimising cold bridging
- Ensuring fabric measures due not create risk of interstitial condensation
- Preventing summer overheating
72

Design Team Approach
73
Adopting whole dwelling energy improvement plan
- Aligned with current and future energy needs of occupants
- Takes account of capital costs, savings, enhanced comfort and
environment
- Future proofed approach
- Identifies opportunities to integrate measures such as AT with building
works
Value for money = shorter payback = greater ROI = happy customer = better business
A happy customer = better business

Sales Advisor – Sean Ruane
- First introduction
- Sell the long term benefits of retrofitting your home
- Sell the process needed to deliver the right solution
- Sell the solution and the measures contained within it
- Sell the upfront cost of carrying out the works
- Ease concerns over the disruption to family life
- Sell the benefits of becoming an advocate for other HO’s once works are complete
Key Roles & Responsibilities – Sales Advisor
74

Building Surveyor – Ger Lawlor
- Taking a whole house approach to their building survey
- Accurately Recording Key information
- Building layout
- Age of building
- Wall, roof and floor types
- Size and heights of rooms
- Widths of stairs, hallways, doorways and side passageways
- Existing ventilation
- Access and space to complete works
- Adjacent boundary's and public footpaths
- Existing services, fittings and fixtures, fuel types
- Existing facades or elevations – listed buildings
- Potential Impacts on Wildlife
- Attention to Detail!
- Can’t presume anything
Key Roles & Responsibilities – Building Surveyor
75

Building Surveyor
- Building Services
- Heating and controls
- Mechanical ventilation
- Lighting
- Electrical cabling
- Identifying existing issues at early stage
- Exposure of the building
- Cavity wall condition
- Damp and condensation, dry/wet rot
- Potential Radon Issues
- Asbestos
- Air permeability (AT)
- Condition of existing windows and doors
Key Roles & Responsibilities – Building Surveyor
76

BER Assessor – Dietrich Pfeiffer
Energy Improvement Designer
- Fabric & Ventilation
- Pre BER Assessment
- Post BER Technical Evaluation
- Fabric Specifications
- U-Value Calculations
- Condensation Risk Analysis
- Airtightness Plan
- Mechanical Ventilation Design
Key Roles & Responsibilities – BER Assessor
77

- Heating & Renewables
- Room by room heat loss calculations
- Heating System Design
- Heat Pump Sizing
- Rad/UF sizing
- HWC Sizing
- Lighting Upgrades
- Solar Thermal/PV Design
78

- Design Considerations when selecting interventions
- Budget
- Lifecycle operating costs (longer term view)
- Thermal comfort
- Level of disruption
- Period/sequence of which improvements should take
place
- Desired energy performance of improvement
79

Project Manager – Thomas Ryan
- Design Review
- Review practicality/feasibility of design
- Identify potential hidden costs
- Identify additional works associated with the
implementation of measures proposed
- Identify ways to simplify and reduce
costs/mitigate against additional costs
- Make costing recommendations
Key Roles & Responsibilities – Project Manager
80

Project Manager – Thomas Ryan
- Project Management
- Core PM Responsibilities
- Management and coordination of all measures
- Quality Management
- Health & Safety
- Budgetary and time management
- Homeowner/Client Engagement
- Clearing communicating roles and responsibilities for all stakeholders in the project
including the HO
- Clearly communicating how all of the works are to be managed and coordinated
- Keeping the HO fully informed throughout the entire lifecycle of the works
- Managing expectations of HO’s
- Providing HO with ongoing customer service throughout the project
Key Roles & Responsibilities – Project Manager
81

Technical Evaluation
82

Technical Evaluation
83

Quantity Surveyor – Oisin Quinn
- Generating Detailed Cost Proposals for,
- All Measures of works as set out in improvement design
- Value Engineering of Design
- Reviewing equal, approved alternative suppliers, manufacturers for each
measure
- Account Management
- Valuations
- Claims
- Variations
Key Roles & Responsibilities – Quantity Surveyor
84

- Communication, communication, communication
- PM’s serves as key engagement point for HO’s
- Good customer service requires good communication skills
- PM’s technical knowledge provides high level of confidence for HO
- Important to manage HO expectations throughout the project
- Homeowners success of a project is subjective. Not objective.
- Poor communication can undermine the success of the project in the eyes of a HO!
The Importance of good PM Skills
85
Project Success = Positive Customers Experience
Positive Customer Experience = Good Communication
Customer service standards will determine
the HO’s overall experience of a successful project

Tools needed to get the job done!
- Combined Team Skills and Experience Required to deliver successful projects
- Qualifications in the areas of
- Building Surveying
- Building Technology
- Engineering
- Project Management
- Advanced knowledge of,
- SR54 Code of Practice
- U Value calculations
- Condensation risk analysis
- Heating system/heat pump design
- Airtightness measures and solutions
- Mechanical Ventilation
- Solar Thermal/Solar PV
Appropriate Qualifications, Skills and Tools
86

Quality Management System
- Training
- All installers are provided with a mandatory quality management
induction
Quality Assurance and Monitoring
87

Quality Management System
- Validation
- Use of a Quality Management App to capture
photographic evidence of installation measures
- All PM’s are required to also complete stage
inspections using the same Quality
Management App
- Declarations and inspection forms are
mandatory to release payments to installers
- All measures are audited by CHS QA upon
completion of the works
- Installers have 5 days to complete reworks on
their behalf or third parties will be engaged to
do it on their behalf
Quality Assurance and Monitoring
88

Communication has a huge impact on a
projects success!
- Communication, communication, communication
- Good customer service requires good
communication skills
- Its essential in order to manage HO
expectations throughout the project
- Strongly advise use of CRM
Communication with HO throughout Retrofit Journey
89

Focus on the destination, not the journey
- Simplify the goal
- Use the BER rating as a goal, instead of various mixes of upgrades
- Simplify the message
- A BER for your home is equivalent to an NCT for your car
- A higher BER = higher comfort = higher savings
- Simplify the process
- Know your starting point
- Set your destination
- Roadmap the journey
Demystifying Retrofit Strategies & Technologies
90

Learnings
- Design Approach
- Whole dwelling energy improvement plan
- Appropriate skills, qualifications and tools
- Understand what is needed and have it in place at the start
- Quality Management, Right first time approach
- Detailed survey
- Upfront design
- Less unknowns
- Smoother, more successful outcomes
- Keep it simple
- Message, language and process
Summary
91

The Sustainable Energy Authority of Ireland is partly financed by Ireland’s EU Structural Funds Programme co-funded by the Irish Government and the
European Union.
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Risk mitigation strategies for retrofits

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