Schematic design

One building model. Structure, services, cost and programme.

Describe a building once — height, floor plate, use, ground conditions — and GenXGrid sizes the frame, designs the foundations, lays out the services, measures the cost and derives the construction programme. Each stage reads the one before it, so the estimate is measured off the members that were actually designed and the programme is built from the quantities that were actually taken off.

What it covers

Nine areas, each feeding the next. Nothing here is a placeholder or a lookup table dressed up as a calculation.

Structure

Member design and code checks

Every column, beam, wall and slab sized and checked against ASCE 7 loads, ACI 318 concrete and AISC 360 steel, with utilisation reported per member.

Geotechnical

Foundations from real reactions

Spread footings, rafts and pile groups designed from the column reactions above, through layered soil profiles, with settlement, liquefaction, lateral capacity and pile downdrag.

Services

MEP sized, routed and coordinated

Loads by orientation, plant selected in whole units with standby, ducts and pipes limited by velocity and pressure gradient, index runs priced through to fan and pump duties.

Vertical transport

Lift traffic analysis

Up-peak round-trip calculation against handling-capacity and interval targets, with rise zoning where a single group cannot meet them.

Fire & public health

Sprinklers, smoke and drainage

Sprinkler hydraulics from the most remote design area, stair pressurisation checked on door-opening force, foul and storm drainage through to the invert at the site boundary.

Cost

Measured, not guessed

Quantities taken off the designed elements and priced from an editable rate library, with regional and escalation factors, and a benchmark band that matches the scope actually measured.

Programme

Schedule derived from the model

Work breakdown from the elements, durations from quantities over crew productivity, critical path, resource levelling, earned value and a 4D view of the frame going up.

Deliverables

Drawings and IFC

A dimensioned sheet set with title blocks, schedules and revisions, plus an IFC4 export with proper classes, profiles and property sets, verified to round-trip.

Energy

8,760-hour simulation

Annual energy, carbon and load factors on a dynamic thermal network, zone by zone, against measured or synthetic weather.

How it fits together

The order matters. Each stage consumes the output of the one before, which is why the numbers agree with each other.

01

Describe the building

Floors, floor-to-floor, plate area, use, structural system, location and seismic zone.

02

Design the frame

Loads to ASCE 7, then every member sized and checked. Column base reactions fall out of it.

03

Found it

Those reactions drive the foundation choice — pads, raft or piles — gated on settlement as well as capacity.

04

Service it

Loads from occupancy and orientation size the plant, the risers and the distribution, then coordinate against the frame that already exists.

05

Measure and price it

Quantities come off the designed elements — not off a rate per square metre — and are priced through the library.

06

Programme it

The same quantities become durations, sequenced the way a building actually goes up, and solved for the critical path.

Every figure states what it is based on

A number without its basis is not usable by an engineer. Results carry the method, the assumption and the thing that would change the answer.

Pressurisation governed by the closed door case at 14.2 m³/s per stair Door force 100 N of 100 N allowed The pressure that keeps smoke out is the same pressure holding the door shut. The two criteria meet almost exactly at 50 Pa on a standard leaf, which is why this is the check that fails. A wider door makes it worse, not better — force grows with area.

That is the shape of every result. Where two methods disagree, both are shown — a population rule of thumb gives eight lifts for a tower where the traffic analysis gives fourteen, and the app tells you which governs and why, rather than quietly picking one.

What it is not

This is a schematic design tool. It is meant to size a building, reserve the space its services need, and set a budget and a programme early enough for those decisions to still be cheap.

Not a substitute for a licensed engineer

Every output is preliminary. Structural results come from a simplified model, not a full 3D analysis; foundations assume characteristic soil values rather than a site investigation; services are sized on load rates rather than a room-by-room model, and the index run is a representative path rather than a coordinated route.

Deliberately outside its scope:

  • Connection design and detailing
  • Tenant fit-out beyond Cat A, external works and professional fees
  • CFD for smoke movement — a two-layer zone model is used instead, and it says where that stops being valid
  • Document workflows: RFIs, submittals and approvals

These exclusions are listed in the product itself, next to the numbers they qualify, and a test fails the build if the code gains a capability while the documentation still claims it lacks one.

Questions

These are also published as structured data, so an answer engine quoting this page quotes the same wording rather than paraphrasing it.

What is GenXGrid?

Schematic design software for high-rise buildings. From one building description — height, floor plate, use, ground conditions — it sizes the structural frame, designs the foundations, lays out the building services, measures the cost and derives the construction programme. Each stage consumes the output of the one before, so the cost estimate is measured off members that were actually designed.

Which design codes does it use?

Structural loads follow ASCE 7, concrete design ACI 318 and steel design AISC 360. Foundations use Vesic and Terzaghi bearing capacity, Broms lateral pile capacity and simplified Seed and Idriss liquefaction screening. Services use ASHRAE and CIBSE load criteria, Darcy-Weisbach pressure drop, Hazen-Williams for sprinkler hydraulics and CIBSE Guide D for lift traffic.

Can it replace a structural engineer?

No. Every output is preliminary and the software says so alongside its results. The structural model is simplified rather than a full 3D finite element analysis, foundations assume characteristic soil values rather than a site investigation, and connection design and detailing are outside its scope. It is meant to size a building and set a budget and programme early, when those decisions are still cheap to change.

Does it export BIM models?

Yes — IFC4, with proper IFC classes, section profiles, materials and property sets, covering structural elements, services distribution, plant, lifts and fit-out coverings. The export is verified to round-trip: the file is re-read and checked against the model it came from.

How is the cost estimated?

Quantities are measured off the designed elements — concrete volumes, reinforcement tonnage, formwork areas, facade area, duct and pipe lengths — rather than applied as a rate per square metre. They are priced from an editable rate library with regional and escalation factors, grouped into CSI MasterFormat divisions, and compared against a benchmark band matched to the scope actually measured. Items that cannot be priced are reported rather than silently dropped.

What does it not do?

No full 3D finite element analysis, connection design, site investigation, room-by-room load modelling, coordinated services routing, or CFD for smoke movement — a two-layer zone model is used instead, and it states where that stops being valid. Document workflows such as RFIs and submittals are deliberately not built. These exclusions are listed inside the product, next to the numbers they qualify.

Start with a building

Create a project, describe a tower, and run it through. No configuration needed to look around.