Draft 2019 amendment to 2004 edition of Technical Guidance Document C (Site Preparation and Resistance to Moisture) to the Building Regulations.

The notification is not related to any one specific construction product / service.

Regulations and technical guidance relate to use of products and methods in the design and construction of new buildings and in material alterations to existing buildings.

Irish Building Regulations 1997 - 2019 set out the legal requirements for the construction of new buildings (including dwellings), extensions to existing buildings as well as for material alterations and certain material changes of use to existing buildings. The related Technical Guidance Documents (Parts A - M respectively) provide technical guidance on how to comply with the regulations in practical terms.

The Technical Guidance Document C is being amended to refer to the revised Standard Recommendation, S.R.21:2014 + A1:2016 Guidance on the use of I.S. EN 13242:2002+A1:2007 Aggregates for unbound and hyrdaulically bound materials for use in civil engineering work and road construction.

Under Part D of the Second Schedule to the Regulations (which concerns Materials and Workmanship), provision is made for an “equivalence clause” which permits the use of materials manufactured to the technical specifications of Member States of the European Economic Area. Mutual recognition provisions of Part D (Materials and workmanship) of the Second Schedule to the Building Regulations are currently in force and will continue to operate. Part D (Materials and Workmanship) is cross-referenced in TGD C so that designers are reminded and take account of important requirements dealt with in another part of the Building Regulations.

The proposed changes are to the following parts of the Technical Guidance Document only:

• Transitional Arrangements (Pg. 2) – New transitional arrangements pursuant to the additional guidance included.

• Paragraph 3.1.4 (b) (Pg.17) – New minimum bed thickness added and reference to S.R. 21 updated

• Paragraph 3.1.4 (d) (Pg. 17) – New description of the hardcore gradings provided, as per S.R.21:2104+A1:2016

• Diagram 4 (Pg. 18) – Updated diagram added showing three allowable options for hardcore placement

• Standards and other references (Pg.24) – Reference to S.R. 21 updated to read S.R. 21:2014+A1:2016