The bay method of estimating
The bay method of estimating, is an approach used to estimate, costs, materials amounts, quanitities or volumes where a certain elements are repetitive. The term bay usually refers to a compartment or section of a building that repeats, as such it is often used for buildings that have multiple and similar visible compartments such as factory units, warehouses, garages or transport interchanges.
The quantities of materials and/or labour, and thus costs of a single compartment is calculated by estimating in detail through measurements off drawings or 3D models (in the case of BIM, often using material take-off). Then the single unit value is multiplied by the number of compartments or units to be constructed. The individual compartments, units, rooms, elements or bays of the building should be identical or at least very similar for the estimating method to be accurate.
There are many different types of estimating with the bay method of estimating being just one approach. It is worth noting that, in general traditional approaches to the estimating of building quantities have changed with the introduction of CAD, to 3D CAD and modelling, and through to the employment of Building Information Modelling or BIM.
[edit] Related articles on Designing Buildings
- Analogous estimating.
- Approximate bill of quantities.
- Approximate quantities cost plan.
- Bill of quantities.
- Common mistakes in bill of quantities.
- Comparison of SMM7 with NRM2.
- Cost estimating.
- Cost plan.
- Cost.
- Elemental cost plan.
- Elemental estimating.
- Estimate.
- Extra over (EO).
- How to take off construction works.
- Measured quantity.
- New Rules of Measurement.
- Operational rate estimating.
- Parametric estimating.
- Payment.
- Price.
- Procurement.
- Spot items.
- Standard Method of Measurement (SMM7).
- Taking off construction works.
- Top down and bottom up estimating.
- Unit rate estimating.
- Working up construction works.
Featured articles and news
A case study and a warning to would-be developers
Creating four dwellings for people to come home to... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.
Futurebuild and UK Construction Week London Unite
Creating the UK’s Built Environment Super Event and over 25 other key partnerships.
Welsh and Scottish 2026 elections
Manifestos for the built environment for upcoming same May day elections.
Advancing BIM education with a competency framework
“We don’t need people who can just draw in 3D. We need people who can think in data.”