Self-Build Glossary

Self-Build involves a lot of unfamiliar language. Some of this language is technical, some contractual, some regulatory, and some is simply industry shorthand that people use as if everyone knows what it means. Most self-builders do not, and there is no reason why they should.

This is a practical glossary for Self-Builders, organised by theme. Use it to make sense of the terminology you’ll encounter as your project moves from idea to a completed home.

Planning, Design and Pre-Construction

The terms you’ll encounter before anything is built - where most of the important decisions are made.

Air Tightness Test
Measures how much unwanted air escapes from the building. A key part of energy performance and Building Regulations compliance.

Architect
Designs your home and typically leads the planning and technical design process.

As-Built Drawings
Updated drawings showing what was actually constructed; useful for records, maintenance and future changes.

Building Regulations
The standards your home must meet for structure, fire safety, insulation, ventilation and more.

Condition Discharge
Providing the information required to satisfy planning conditions before certain works can begin.

Design and Access Statement
Explains the thinking behind the design and how the site will be accessed.

Energy Assessor
Produces the SAP calculation, based on U-values, air-tightness, energy efficiency and renewable technologies.

Feasibility Study
An early sense-check: is the project workable in terms of planning, cost and constraints?

Ground Conditions
What’s beneath the site. This directly affects foundation design, drainage and cost.

Local Planning Authority
The council body that determines planning applications.

Outline Planning Permission
Approval in principle, with detailed design agreed later.

Planning Conditions
Requirements attached to planning approval that must be met as the project progresses.

Planning Permission
Formal consent to build.

Principal Designer
Responsible for managing health and safety during the design stage under CDM Regulations.

Renewable Technologies
Systems that generate energy from sustainable sources such as the sun, air or ground (e.g. solar panels and heat pumps), used to reduce energy demand, running costs and carbon emissions.

Reserved Matters
The detailed aspects of a scheme (such as layout or appearance) approved after outline permission.

Serviced Plot
A plot with utilities already brought to or near the boundary.

Site Investigation
Surveys and testing to understand ground conditions and constraints.

Specification
Defines the materials, products and quality standards required.

Structural Engineer
Designs the structural elements: foundations, beams, floors, load-bearing walls, and drainage.

Technical Design
Developing the design into detailed information suitable for pricing and construction.

Compliance, Standards and Certification

The checks and standards that ensure your home is safe, efficient and compliant.

Building Control
Confirms compliance with Building Regulations through plan checks and site inspections.

CDM Regulations (CDM stands for Construction, Design and Management Regulations)
Set out health and safety responsibilities for clients, designers and contractors.

EPC (Energy Performance Certificate)
Rates the energy efficiency of your home.

Handover Information
The documents you receive at completion - certificates, manuals and key information about your home.

HEM (Home Energy Model)
The future replacement for SAP, used to assess energy performance.

Inspection Stages
Key points during construction where work must be checked before it is covered up.

Registered Building Control Approver
A private organisation authorised to carry out Building Control instead of the local authority.

SAP (Standard Assessment Procedure)
The current method for assessing energy performance (being phased out).

Structural Warranty
Typically a 10-year policy covering structural defects. Often required by lenders.

Structural Warranty Auditor
A surveyor who audits the design and construction on behalf of the Structural Warranty Provider.

U-Value
A measure of how easily heat passes through a building element (such as a wall, roof or window). The lower the U-value, the better the insulation and energy efficiency.

Cost, Budget and Finance

Where the money goes and how to stay in control of it.

Budget
The total amount available, including construction, fees, surveys, approvals and contingency.

Cash Flow Forecast
Shows when funds will be needed throughout the project.

Construction Cost
The cost of building the house itself.

Contingency
A reserve for the unknown - because there is always something.

Cost Plan
A structured breakdown of expected costs, refined as the design develops.

Final Account
The agreed total cost at the end of the project.

Gross Internal Area (GIA)
Total usable floor area, often used to benchmark cost.

Interim Valuation
Assessment of work completed to support staged payments.

Overheads and Profit
The contractor’s allowance for running their business and making a profit.

Prime Cost Item
An allowance for items not yet selected (e.g. kitchens, tiles).

Provisional Sum
An allowance for work not fully defined at the time of pricing.

Stage Payments
Payments made as the build progresses.

Tender
The process of obtaining prices from contractors.

Tender Return
The contractor’s submitted price and proposal.

Value Engineering
Reducing cost without undermining the core quality or intent.

Variation
A change to scope or specification usually with a cost and/or time impact.

Construction, Quality and Delivery

The language of the build itself - from first dig to handover.

Construction Phase Plan
The project’s health and safety plan before work starts.

Construction Programme
The timeline showing how the build will be sequenced.

Defects Liability Period
A period after completion where defects must be corrected.

Foundations
The part of the building that transfers loads into the ground.

Handover
The point where the completed home is passed to you with keys and documentation.

Latent Defect
A defect that only becomes apparent after completion.

Method Statement
Explains how specific work will be carried out safely and correctly.

Practical Completion
The point where the home can be occupied, with only minor items outstanding.

Programme
The planned sequence and duration of works.

Retention
A small sum sometimes held back until defects are resolved.

Risk Assessment
Identifies the risks associated with the design or construction.

Site Manager
Plans and oversees the day-to-day site activity.

Snagging
Identifying and fixing minor defects.

Subcontractor
Specialist trade carrying out part of the work.

Temporary Works
Short-term structures or supports, such as scaffolding.

Workmanship
The standard of how the work is actually executed.

Roles and Responsibilities

Who does what and who is accountable for what.

Client
You - the person commissioning and funding the project.

Contract Administrator
Administers the building contract and manages formal instructions.

Principal Contractor
The organisation building your home. Also responsible for managing site health & safety under CDM.

Project Manager
Co-ordinates the project to keep time, cost, quality and risk under control.

Project Controls, Risk and Decision-Making

The disciplines that keep the project realistic, structured and under control.

Critical Path
The sequence of activities that determines the overall project duration.

Key Stage Deliverables
The information and decisions required before moving forward.

Procurement Route
How design responsibility and construction are organised.

Project Execution Plan
Sets out how the project will be managed.

Risk Register
Identifies risks and how they will be handled.

Scope
What is included in the project.

Scope Creep
Gradual expansion of scope, often without recognising the consequences.

Trade-Off
Balancing competing priorities (cost, time, quality).

Value for Money
Getting the right outcome, not simply the lowest cost.