Current project · project — · revision — · envelope explorer

See what each thermal decision changes.

Explore the same building geometry with different envelope specifications. Live results use the fast comparative model; the EnergyPlus report is the higher-fidelity hourly assessment.

Live model

Quick comparative model Use the live result to compare orientation and specification choices. Absolute demand and the size of any benefit remain indicative.

Flagship cross-check The live model was higher than EnergyPlus at every tested orientation in the locked flagship case. This conservative result is not yet a universal claim.

EnergyPlus & compliance EnergyPlus is the preferred higher-fidelity technical assessment. It remains input-dependent; compliance is determined separately.

Select a saved project before opening the thermal estimator.

Build specification

The window choice saves immediately so the Opening Schedule and Overall Budget stay aligned. Other changes remain exploratory until you save them to this project.

Try another orientation Rotate the building for this thermal page only.

N E S W ⌂

Drag the wheel to rotate the building · use arrow keys for precise steps

Saved project aspect · drag anywhere on the compass to test another orientation.

Windows

Selected joinery

Stark Windows uPVC is shown as planned, but cannot be selected until supplier pricing and thermal evidence are added. Fisher remains in the locked validation evidence only.

External wall

Roof insulation

Under-slab insulation

External door

Airtightness

Ventilation

Calculation model

Choose which model drives every annual load, cost, comparison and saved report. Hourly results are indicative and independently unvalidated; neither option is an H1 compliance result.

Weather location · NIWA TMY3

H1 climate zone · automatic Zone 6

The NIWA location drives both models: monthly mode aggregates its 8,760 hours, while hourly mode reads every interval. Its H1 zone is linked automatically from MBIE’s weather-area mapping and affects the reference comparison only.

The starting weather is the authoritative Project Setup location. Exploratory changes here are not saved; reports remain tied to Project Setup. Evidence status is stated separately for each model component below.

Design weather — Drives annual kWh and cost

H1 reference — Reference bars only

Specification Project basis Reports use this basis

Comfort and shading

Choose the indoor comfort range, then describe how much sun reaches the windows.

Heat to °C

Cool above °C

Internal gains (W/m²)

Internal gains are currently constant because project occupancy schedules are not yet captured. Summer cooling uses the selected mechanical-ventilation airflow and automatic MVHR bypass plus geometry- and weather-derived airflow from supported openable windows and doors.

Year-round: not derived Summer: manual override

Solar admission has not yet been checked against this project's eaves and reveals.

Year-round obstruction

Summer eaves, blinds or shutters

Summer shading reduces overheating risk. South-facing glass is left unchanged by the simple preset because it receives little direct summer sun in New Zealand.

Advanced: adjust each direction

Year-round % Summer % N E S W

100% means all available sun reaches the glass; lower percentages mean more shading.

The default design band is 20–24°C. It does not claim the percentage of occupied hours within that band; that requires an hourly comfort model.

Estimated running cost

Starts with declared defaults of 40¢/kWh and a typical heat pump. SCOP means seasonal coefficient of performance: 3.5 means about 3.5 units of heat for each unit of electricity across the heating season. Change either assumption here to see the impact. Daily fixed charges are excluded.

Electricity rate (c/kWh)

How is the home heated?

This home will use air conditioning

Advanced: equipment rating and tariff evidence

Seasonal efficiency describes how much heating the system supplies for each unit of energy it uses. For heat pumps, this is the seasonal efficiency (SCOP).

Heating seasonal efficiency (SCOP)

Cooling efficiency (COP)

Tariff source (optional)

Tariff date (optional)

Window price and payback

Use the current EUR to NZD exchange rate. Viking freight and NZ landing charges are then added once per container.

EUR to NZD exchange rate

40 ft shipping containers

Owner-confirmed allowances: EUR 3,500 freight plus NZD 2,000 landing charges per container. Blank uses the planning rule of one container per started 50 m² of joinery; override when the order is packed.

Reports

Exports use the saved project specification and saved orientation.

EnergyPlus models the saved building hour by hour and is the preferred technical assessment. Its result is still only as reliable as the project geometry, weather, constructions, schedules and controls supplied; it is not a guarantee of completed-building energy use or a compliance determination.

BETA runtime: EnergyPlus 25.2.0 available.

Annual space-conditioning demand

— kWh/m²·yr — energy used per square metre of floor, per year kWh/m²·yr

Heating — Cooling —

Comfort, ventilation, solar admission and input sensitivity affect this result.

What affects this result

Openable-window cooling is modelled before active cooling. A no-summer-ventilation sensitivity will appear here. Comfort band: 20–24°C. Percentage of occupied hours within the band is not calculated by this monthly model. Gain-sensitivity diagnostic pending.

Estimated annual running cost — Estimate Using declared defaults of 40¢/kWh and a typical heat pump. SCOP (seasonal coefficient of performance) 3.5 means about 3.5 units of heat for each unit of electricity across the heating season. Complete the running-cost choices to compare this build with a typical NZ code-built house.

Same house, compared simply

Compare this design with a typical NZ code-built house using the same geometry. The statutory H1/VM1 basis is shown separately.

Annual demand

This buildDesign weather

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NZ code-built houseSame geometry · code-minimum envelope

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H1/VM1 referenceCompliance basis · services held equal · reference zone

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The bar scale adjusts to the highest result shown. Use the numbers at right for absolute changes.

Reference details

The indicative code-built house uses the same geometry with a code-minimum envelope, assumed 5 ACH50 and no heat recovery.

The H1/VM1 reference holds geometry, airtightness, ventilation, MVHR and services equal; only insulation and glazing change to code minimum.

Extra capital cost — Against the indicative NZ code-built house

Annual energy saving — Against a typical NZ code-built house

Simple payback — Indicative; excludes finance and escalation

Capital-cost breakdown

Building geometry used

Net external areas come from the current project model. Openings are shown separately and are not double-counted in the opaque wall area.

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Net external walls — Opaque wall area after openings

Gross glazed openings — Windows and glazed openings

External doors — Opaque external doors

Roof — Modelled external roof area

Treated floor — Conditioned floor area

Gross heat loss — Envelope, junctions and ventilation

Usable free gains — Solar and internal gains used by the calculation

Net conditioning demand — Heating plus active cooling after usable gains

Inputs and external check

Every result-driving input carries its value, source and current evidence status.

Fisher validates the monthly method, not this building’s assumptions.

Gross-to-net amplification — Diagnostic pending

Fisher monthly anchor — Term-by-term external reconciliation

Component evidence status

Component	Status	Basis

Input provenance register

Input	Value	Source	Status

Fisher term-by-term reconciliation

Term	Fisher	ICF Designer	Residual

Open the locked Fisher validation case

See what each thermal decision changes.

Specification changed

Same house, compared simply

Annual demand

Building geometry used

Inputs and external check

This is a temporary thermal scenario

Specification changed

Same house, compared simply

Annual demand

Building geometry used

Inputs and external check

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