Practical post 25: Septic Tanks | Waste Water Treatment – BC(A)R SI.9

by Bregs Blog admin team

GTO Septic System Picture

Practical post 25: Septic Tanks & Waste Water under the new Building Control Regulations

Septic tanks come under Part H of the building regulations. Anyone constructing a new house (or extending by more than 40m2) after 1 March 2014 which has a septic tank or other waste water treatment systems will need to comply with new requirements.

Part H is here:  Publications Development and Housing-BuildingStandards.pdf

The EPA Code of Practice is at

Under the new regulations, the design of the system will have to be certified by a competent person before the Commencement Notice is lodged. This construction of the system will have to be inspected during construction and certified at completion.

Design and Assigned Certifiers for these projects need to make sure that ‘competent persons’ sign these Ancillary Certificates at Commencement and Completion and that the installer has PI insurance for any defective design.

Anyone replacing an existing system (who is not building or extending a house at the same time) is exempt from these new controls.


Other Posts in this series:

Practical Post 24: New Part K & J of Building Regulations

Practical post 23: Design Build contracts- need a barge pole?

Practical post 22: Change of Owner

Practical post 21: Variations 

For Practical Post Series 1-20 

NOTE: This series of posts is not meant to undermine or be in opposition to any professional advice from registered representative bodies: rather it is to offer additional technical aids to those that find themselves in the position of having to deal with SI.9 in it’s current form at present. As with all information posted on the Blog we urge all practitioners to check with their respective professional bodies before assuming any roles or duties under Building Control (Amendment) regulation (SI.9 of 2014). We hope to post a number of these practical posts and list in one area, so home owners, SME’s and professionals can drop in and click on a particular topic to get summary information that may be useful to them while working under the newregulations.