Indirect heat interface unit
Heat Interface Units (BG 62/2015) was written by Reginald Brown and published by BSRIA in December 2015. It states: ‘An indirect HIU (heat interface unit) in this guide refers to an HIU where there is hydraulic separation between the heat network and the secondary space heating circuits. The secondary heat distribution system must therefore include independent provisions for filling, pressurisation, circulation and water treatment. An indirect HIU for residential consumers may include separate plate heat exchangers for heating and domestic hot water. These heat exchangers are sometimes referred to as the “heating plate” and the “hot water plate” respectively.'
More details of the key features and construction of direct and indirect HIUs, including variations associated with domestic hot water production and storage, are given in Sections 7 and 8 of the guide.
--BSRIA
[edit] Related articles on Designing Buildings
- A technical guide to district heating (FB 72).
- Big growth in district heating markets - now and on the horizon.
- BSRIA articles.
- BSRIA definitions.
- BSRIA guide to heat interface units.
- Communal heating.
- Direct heat interface unit.
- District energy networks
- Domestic micro-generation.
- Heat interface unit.
Featured articles and news
We're expanding our collaborative mission by launching DB Intelligence, an exclusive market research advisory panel. Built environment professionals can now get paid to share their expertise on industry trends, products and services.
Panel members receive direct financial incentives for participating in research projects like short surveys, 1-2-1 interviews and focus groups. Register today to shape the future of the construction sector.
Planning condition discharge in England and Wales
A brief exoplanation from a building compliance expert, with further links.
Overheating guidance and tools for building designers
Guidance for dealing with element of building fabric control that have increasing importance.
Shading for housing, a design guide
From the Good Homes Alliance and British Blind and Shutter Association.
UK Standard Skills Classification (SSC)
A shared framework for describing skills needs.
Social media ban consultation comes to close
CIOB urges UK Government to consider social media’s role in careers guidance in ban debate.
The latest of eight Skills England apprenticeship units
The addition of battery manufacturing welcomed by ECA with a warning about the risks of fast-tracked apprenticeship units.
Building Control Independent Panel final report
A precis of a key report led by Dame Hackitt with full recommendations and link to the government response.
Building Safety recap April, 2026
A short and longer run-through of the month, with links to further information and sources.
CIAT May 2026 briefing.
From medieval scribes to modern word art.
ECA welcomes crackdown on late payment and push for clean energy, whilst CIOB seek fixed cladding removal timeframes.
Cyber Security in the Built Environment
Protecting projects, data, and digital assets: A CIOB Academy TIS.
Managing competence in the built environment
ITFG publishes new industry guide on how to meet the ICC principles.
The UK's campaign to reduce noise pollution: Mythbusting, articles and topic guides.