My thoughts regarding replacing an existing Hot Water Cylinder that does not have an existing drained safe tray installed underneath it:
- If it is impractical to install a drained safe tray (for instance it is not practical to install the 40mm drain required due to location of the existing HWC and concrete foundations which would require significant excavation and alteration) then it would not be required.
- If the location of the new HWC is different from the existing, then a drained safe tray should be installed.
- If it is reasonable practical to install a drained safe tray, then one should be installed
Support for this conclusion that a safe tray would not be required if impractical is taken from Section 112 of the Building Act 2004. This section discusses 'Alterations to existing buildings' and considerations that the local TA must consider before issuing a building consent.
This section discusses that a building consent can be issued 'if after the alteration, the building will if it did not comply with the other provisions of the building code immediately before the building work began, continue to comply at least to the same extent as it did then comply'