Margin
The Code of Estimating Practice, seventh edition, published by the Chartered Institute of Building (CIOB) in 2009 suggests the term ‘margin’ refers to:
‘The sum that is required by an organisation, from a project, as a contribution towards its head office overheads and profit.’
Where profit is the money the project makes after accounting for all costs and expenses, and overheads refer to the costs of running the company, often described as head office administrative costs (although in some cases there may also be factory or manufacturing overheads).
Confusingly, profit may also be referred to as a ‘profit margin’. Profit margin is the percentage of the gross revenue that represents profit.
A report published in July 2018 by Construction Manager and Commercial Risk Management found a worrying gap between the margins construction professionals think they should be earning and what they actually earn. For example, nearly two-thirds of respondents said they would expect the appropriate profit margin for a main contractor under a design-and-build contract should be above 5%. In fact this is well above the average achieved in the industry.
Jason Farnell, managing director of Commercial Risk Management, said; "The survey responses are communicating clearly that the ratio of risk to reward in contracting is seriously imbalanced – put simply, the margins that contractors may expect to earn from projects is insufficient compensation for the uncertainty and risk exposure they face in delivering them.”
NB: The term ‘mark up’ refers to the sum added to a cost estimate to arrive at a tender sum, including margin, allowances for exceptional risks, and adjustments for commercial matters such as financial charges, cash-flow, opportunities (scope) and competition.
Short Guide, Maintaining Your Home, published, on 1 November 2014 by Historic Scotland, defines margins as: ‘protruding masonry framing an opening or emphasising the angle of a building. Most are raised (usually adopted when the building was to be harled but sometimes used decoratively).’
[edit] Related articles on Designing Buildings
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.