Structural engineering is a field that’s full of highly technical hurdles and complicated calculations, but one of the most challenging aspects of our job is explaining the work we do to our self-build clients. For someone with no background in engineering or construction, our language can almost seem alien.

When planning for a structural engineer to jump on your project, it’s imperative to do your research on the role they will be undertaking.

That’s why we’ve put together this handy Jargon guide to help you navigate our website and the intricate world of structural engineering & design. If you have any suggestions, please let us know!

Do you have any question regarding your project?

Contact us, and we will help you move on with your Self Build dream!

ACS – Allan Corfield Structures Ltd. Structural engineers specialising in residential design utilising Modern Methods of Construction.

Bar Bending Schedule – A list of all the reinforcement bars required for your structure. Can include multiple bar types with varying diameters, lengths and bends. Required for ICF walls, retaining walls and ground beams.

Borehole – A narrow shaft drilled in the ground as part of an intrusive site investigation. They can be dug vertically or horizontally to identify what’s in the ground.

Bearing Strata – The natural layer of ground that can bear the weight of a structure without compressing or shifting.

Braced Bay – Used to provide lateral support to a scaffold tower. Also used as compression and tension members for cantilevers to transmit loads back to the main structure.

Building Control – The process of ensuring that a building project complies with building regulations and safety standards.

CAD – Computer Aided Design. Our team use this to digitally create 2D drawings and 3D models of our designs before any construction begins.

Civil Engineering – deals with the design, construction, and maintenance of the built environment, including public works such as roads, bridges and structural components of buildings.

Cohesion – The force that holds together molecules or like particles within a soil.

Contractor – Contractors carry out the work on-site, following the drawings and specifications to deliver what has been designed. They are usually split into main or sub-contractors. The main contractor can oversee all the other sub-contractors on site and will either report back to the client or the project manager.

CPD – Continued Professional Development. We are big advocates of CPD at ACS and we use it to expand our knowledge and skillset.

Flitch Plate – Improves the rigidity of a beam, enabling it to carry more weight than a timber beam of similar size. Ideal for creating large, open spaces in homes.

Foundations – The element that connects your building to the ground. It’s located at the very bottom of the construction, in direct contact with the soil.

Frozen Drawings – Drawings that have been finalised and are expected to receive no further amendments.

Gas Monitoring – Used in a site investigation if the site is potentially contaminated with harmful gases. Ensures your project meets the gas protection requirements.

Heave – The process of soil swelling or shrinking, which in turn causes uneven distribution beneath a building foundation.  May result in an increase in the depth of your foundation.

ICF – Insulated Concrete Formwork. Consists of hollow polystyrene blocks, interlocking together to create a mould into which ready-mixed concrete is poured.

Internal Wall – Walls that divide rooms, as opposed to the insides of the external walls. They come in two distinct types: loadbearing. non-loadbearing.

IStructE – The Institution of Structural Engineers. A British professional body for structural engineers.

Joist – A horizontal structural member typically made of solid timber that is placed between beams and walls to support the structure

Load-Bearing – Supporting much of the weight of the overlying parts of a building or other structure (especially of a wall).

MMC – Modern Methods of Construction, such as SIPs, Timber Frame and ICF.


Percolation Testing – Determines the rate of water absorption into the surrounding ground. The procedure measures how long it takes a measured amount of water to drain from a saturated hole dug into the ground. The result determines the suitability and permeability of the soil.

Piling – The process of driving or boring pile foundations beneath a building that is undergoing construction.

Porosity – A measure of the void spaces in a material. Typically used when referring to rocks and soil.

Racking Panel – A solid timber or SIPs wall utilised for the stability of building.

Retaining Wall – Walls used for supporting soil laterally so that it can be retained at different levels on the two sides.

Revit – A common building information modelling software used at ACS. Allows users to design a building and structure and its components in 3D and access building information from the building model’s database.

Self-Build – The creation of an individual home for oneself through a variety of methods. The self-builder can participate in the design and construction of the building, working in conjunction with hired professionals.

SER – Structural Engineers Registration Ltd. Provides and manages registration schemes for the certification of the design of building structures. Applicable to Scotland only.

SIPS – Structural Insulated Panels. A popular method of construction that is typically composed through layering insulations material between two outer boards. 

Site Investigation – Used to collect information and report potential hazards beneath a site. Establishes the type and quality of the ground beneath the proposed building foundations.

Soakaway – A drainage system to assist surface rainwater that doesn’t naturally drain from your property. Used to prevent flooding and to protect a building structure from excess water.

Spread Foundation – The support and distribution of the load of a structure over an area of soil. Designed to transfer the weight of the structure to the underlying soil in a way that prevents unnecessary settlement and subsidence. 

Structural Drawings – Detailed illustrations of the structural components of a building, including the design and specifications. Used to provide a comprehensive layout of how the structure will be constructed.

Structural Engineering – The practice of designing the strength and stability of a structure, such as a building or a bridge.

Structural Inspection – A detailed report on the condition and method of the structural integrity of a property, which identifies any severe defects and potential repairs. Also used on live projects for the engineer to ensure the contractor has understood the drawings

Structural Technician – Part of the design team. Responsible for producing comprehensive detailed design drawings for our Structural engineers and providing technical drawing guidance to the architects.

Structural Warranty – A warranty that covers defects in the design, workmanship, materials and components of your housing unit and protects the homeowner in the event the property suffers physical damage, or the risk of physical damage. 

SUDS – Sustainable Drainage Systems. The practice of designing draining systems that mimic natural drainage and promote infiltration.

Sway Frame – A rigid steel frame that assists in racking and restricts the movement of the structure.

Tensile Strength – The maximum load a material can support without fracture when being stretched, divided by the original cross-sectional area of the material. 

Timber Frame – One of the most popular self-build construction methods. The timber acts as a superstructure, which supports your self-build home entirely.

Transfer Beam – A concentrated beam used to transfer loads to columns.

Trench Fill – A shallow foundation dug to the required foundation depth and then filled with concrete, minimising the need for excavation.

Trial Pit – An excavation of ground to study or sample the composition and identify any existing foundations. Usually dug during a site investigation.

Truss – The span between the internal and external load-bearing walls.  

Type 1 Hardcore – A term for solid materials that aren’t easily degraded. Used in engineered fill below foundations & ground bearing slabs.

Underpinning – A method of construction where the depth of the foundations of a building is increased.

Water Table – The level below the ground where water is encountered. Identified in a site investigation.



Do you have any question regarding your project?

Contact us, and we will help you move on with your Self Build dream!