Zero Carbon.

A zero carbon home, sometimes called an ‘absolute zero carbon’ home, is one which has no carbon emissions and does not rely on offsetting to achieve this.

In practice this means either that the home uses no energy at all, or that whatever energy it does use is both (i) produced in a way that emits no carbon, and (ii) produced on-site or via a dedicated private wire/pipeline.

In the context of housing policy, zero carbon usually refers just to the regulated component of the home’s operational carbon. However, zero carbon definitions do sometimes include unregulated energy and/or embodied energy, which makes standards and compliance harder to calculate and to police. It is important to be sure which definition is being used, and if it is required to calculate unregulated energy to use a reputable method such as that set out in SAP Appendix L.

A zero carbon home must not be confused with a net zero carbon, carbon-neutral or zero carbon ‘ready’ home. The latter definitions are sometimes used when site constraints make it impossible to reach zero carbon on-site.

(Definition taken from “Carbon Jargon”, an NHBC Foundation report, researched and written by Neil Cutland of Sava).