These Acceptable Construction Details (ACDs) focus on thermal bridging and airtightness. This guide will help appropriate persons to achieve the performance standards in the Technical Guidance Document (TGD) to Part L of the Building
Regulations 2008 – Conservation of Fuel and Energy – Dwellings.
The guide is presented in 2 sections. Section 1 discusses the general theory of insulation continuity and airtightness in construction. Section 2, in seven separate parts, provides indicative detail drawings of thermal insulation and airtightness provisions for specific construction interfaces.
A Comment Sheet is also available, for download by anyone who wishes to comment on or propose amendments to any of the details.
The ACDs will be reviewed in the light of experience to ensure they will continue to reflect effective and widespread contemporary approaches.
Section 1 – Introduction and general theory of insulation continuity and air tightness (pdf, 2.5mb)
Section 2 –Acceptable Construction Details
General Details (pdf, 1.23mb)
Cavity Wall Insulation (pdf, 10mb)
External Wall Insulation (pdf, 3.7mb)
Internal Wal Insulation (pdf, 3.9mb)
Timber Frame Insulation (pdf, 2mb)
Steel Frame Insulation (pdf, 2mb)
Cavity Block Insulation (pdf, 2.4mb)
Section 3 – Comment Sheet (doc, 23kb)
Heating and Domestic Hot Water Systems for Dwellings- Achieving Compliance with Part L 2008 (pdf, 1,190kb)
Amendment to Heating & Domestic Hot Water Systems for Dwellings - 29.10.08 (pdf, 56kb)
This is the supporting document referred to in Par 1.4.1 of Technical Guidance Document L - Dwellings 2007. It is a source of guidance on the means of complying with the requirements of the Building Regulations for space heating systems and hot water systems.
Guide to the Condensing Boiler Installment Assessment Procedure for Existing Dwellings (pdf, 345kb)
This document contains the detailed guidance referred to in paragraph 2.2 of Technical Guidance Document L - Dwellings 2007 to assess specific situations where the provision of condensing boilers is not practicable. It is also included as an appendix in the document "Heating and Domestic Hot Water Systems for Dwellings - Achieving Compliance with Part L".
Dwellings Energy Assessment Procedure
The Dwellings Energy Assessment Procedure (DEAP) methodology (external link) required to show compliance of dwellings with Regulation L2(a) of Part L, as amended by the Building Regulations (Amendment) Regulations 2005 (S.I No. 873 of 2005), and contained in the May 2006 Edition of TGD L, can be accessed and downloaded from the Sustainable Energy Authority of Ireland's website.
The following are links to databases which also support the DEAP procedure: -
The Home-heating Appliance Register of Performance (HARP) database (external link) - Sustainable Energy Authority of Ireland
Standard Assessment Procedure (SAP) Appendix Q Ventilation systems database (external link) - see SAP Appendix Q
Windows Energy Performance scheme (WEPs) (external link) - National Standards Authority of Ireland
Product Certification for Air Tightness Testing (external link) - National Standards Authority of Ireland
To Account for Thermal Bridging in DEAP (external link) - Sustainable Energy Authority of Irreland
Part D Compliance
The National Standards Authority of Ireland (NSAI) is Ireland's official standards body and provides a wide range of certification services to enable business demonstrate that Irish goods and services conform to applicable standards. The following links provide information in relation to NSAI Agrément certified systems and installers: -
Agrément Search Page (external link) - National Standards Authority of Ireland
External Thermal Insulating Composite Systems (ETICS) Installers List (external link) - National Standards Authority of Ireland
Cavity Wall Insulation Installers List (external link) - National Standards Authority of Ireland
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Publications & Documents
FAQs for Disability Access Certificates - Regularisation Certificates - 7 Day Notices (doc, 60 kb)
PL11 Guide to the Building Control System (May 2010) (pdf, 249 kb)