Construction Jargon Explained: A Homeowner’s Guide
March 27, 2024by Clive SanhamBuildConstruction0
You should not have to guess what a builder means. This guide explains common terms you may encounter during an extension, conversion or renovation. Ask for any term that affects the price, specification or programme to be defined in your project documents.
Drawings and the structure
- Plans, elevations and sections: drawings showing the layout, outside faces and views through a building. Check the drawing number and revision being used.
- Specification: the written description of materials, products, workmanship and other requirements for the work.
- Foundations: the part of the structure transferring building loads to the ground. Their design depends on the proposed building and site conditions.
- Load-bearing wall: a wall supporting loads from other parts of the building. Have its role assessed before proposing alterations.
- Joist: a structural member that commonly supports a floor or ceiling.
- Stud: an upright member in a framed wall.
- Lintel: a member spanning an opening and supporting loads above it.
The roof and building fabric
- Rafter or roof truss: part of the structure supporting the roof; the form and design vary.
- Flashing: material used to weather a junction or detail, such as where a roof meets a wall.
- Fascia and soffit: respectively the board or face at a roof edge and the underside of an overhang.
- Insulation: material specified to reduce heat transfer. Its performance depends on the complete design and installation.
- U-value: a measure of heat transfer through a building element; a lower value indicates less heat transfer under the stated conditions.
For energy requirements, see our Part L guide.
Stages of the work
- Groundworks: work preparing the site and forming below-ground elements, according to the agreed scope.
- First fix: work generally completed before finishes close things in, such as initial wiring, pipework and certain carpentry.
- Second fix: later installation of fittings and finished components. Agree what each stage includes in your quotation.
- Snagging: identifying outstanding items or defects and recording how they will be dealt with. It is not a substitute for the project’s other inspections and approvals.
- Handover: the agreed process for transferring the completed work, instructions and relevant documents to the customer.
Prices and changes
- Scope of work: what the builder has agreed to carry out, read alongside the drawings and specification.
- Provisional sum or allowance: an amount allowed for an item that is not fully settled. Ask how the final amount will be calculated.
- Variation: a change to the agreed work. Record the price and programme implications and who has approved it.
- Payment milestone: a defined stage linked to the agreed payment schedule.
Our quotation guide explains what to check before comparing offers.
Permissions and certificates
Planning permission, listed building consent and building regulations are separate matters. A completion document should be understood in the context of the system that issued it; it is not a blanket guarantee of every aspect of a project. See our guide to approval routes.
Put the terms in context
See the photographs and description of our South Walsham extension, or ask us about your own proposed work. Clear questions at the start help establish what needs to be designed, specified and priced.
Reviewed September 2026.
