NEST

01 / THE RENOVATION CHALLENGE

Millions of homes.
Individual renovations.

A climate-neutral Europe depends on improving the buildings we already have. Renovating them at scale means using less energy and creating more comfortable homes—while meeting each building’s needs and each household’s preferences.

85–95%of the EU buildings existing in 2020 were expected to still be standing in 2050.

European Commission · Renovation Wave, 2020 ↗Read without animation ↗

02 / SCALE + PERSONALISATION

Many homes.
A personal plan for each.

An inspection defines one home’s needs. Stock-level methods cover many homes, but lose detail per element. The goal is to combine both.

One buildingMany buildings / national stock

More building-specific detail ↑

Detailed assessment

Site inspections, energy audits and building models.

Element-level detail, repeated for each building.

THE RESEARCH GAP

Every building.
Every element.

A building-specific renovation scope at scale, without visiting every home.

A building overview

Currently, inspectors carry out whole-building checks and initial screenings.

One home, without an element-by-element scope.

Stock-level methods

Archetypes, typologies and register-based models.

Wide coverage; average types or a few coarse attributes.
One building ↔ Many buildings / national stock

WHY NOT JUST SEND A WINDOW COMPANY?

First define the work.
Then organise the street.

A street does not tell a contractor which homes need windows, walls or roof work—or who is ready to proceed. A shared scope makes that demand specific.

16 hoursper home
4,000 homes64,000 hours
40 adviser-yearsat 1,600 hours per year

Workload scenario raised in the interview, not measured NEST time savings.

Prepare the scope before the visit. Professionals verify the work; confirmed participation and timing give contractors a credible demand promise.

03 / UNDERSTANDING THE BUILDING · SIMULATION

Simulate the building.
Compare it with reality.

The blue half represents a simulation of the same building. We test possible building conditions, then compare simulated energy consumption with measured use.

SimulationSame geometry and documented construction. Test different building conditions.

Real buildingMeasured energy use compared with simulated energy.

Compare consumption. Keep the closest matches.
Compare simulated and measured consumption on the same energy basis.

Proposed pilot input: about 40 days of meter data, with the resident’s authorisation. Postcode totals do not replace per-home readings.

04 / BUILDING ELEMENTS

Simulate. Compare.
Keep the closest.

We’ll assess the building through multiple elements: walls, windows and doors, roof, floor and HVAC. Select an element to see it in the model.

05 / DEMONSTRATED · SYNTHETIC EXAMPLE

An estimate.
Checked against the truth.

The model estimates wall performance from energy-use data. In this controlled example, we know the wall used to generate that data—so we can check how close the estimate comes.

ONE CONTROLLED EXAMPLE

A close match.

Estimated wall U-value0.626 W/m²K90% model range: 0.615–0.635
Known wall U-value0.622 W/m²KKnown because the data are synthetic

The estimated wall closely matches the known wall. For the illustrative target U ≤ 0.30, both lead to the same 60 mm added-insulation option.

This demonstration uses synthetic data and illustrative prices. It has not been validated for occupied homes; results are not a survey or a contractor quote.

06 / FROM AN ESTIMATE TO A PLAN

From an estimate.
To a renovation budget.

An estimated wall condition helps define an insulation option. Explore the target and see how the budget changes.

Added insulation60 mm
Wall U-value after insulation0.288 W/m²K
Estimated added wall insulation · whole house€7,500–€11,400Planning allowance ±20% planning allowance · rounded outward to €100.
Adjust the budget assumptions

Editable assumptions including VAT. The allowance is not a statistical confidence interval or a contractor quote. Cost = wall area × thickness × material rate + wall area × installation rate. The range applies the chosen planning allowance to that calculation.

Net area 87.74 m² for this prepared house, with window and door openings deducted. Scaffolding, repairs and other renovation work require separate allowances.

07 / Proposed

What must be
proven next.

The next step is to test the approach across many buildings and varied conditions. The neighbourhood illustrates how comparable scopes could be grouped.

  1. Blind multi-building testAssess multiple synthetic buildings without revealing their known condition in advance. Compare the estimates with the known results.
  2. Make known inputs uncertainOne at a time: household behaviour first, then other elements.
  3. Use a different simulator for the truthTest inference without matched physics.
  4. Test real buildingsCompare the assessment with independent inspections and measurements.
  5. Extend element by elementBuild toward a whole renovation scope.

The current results are synthetic. Whole-building scopes, resident-authorised data access and the delivery workflow still need testing with real homes.

08 / NEST PLANNER · PERSONALISATION CONCEPT

Your home.
Your decision.

Trust needs control. The homeowner should be able to correct missing information, compare options and approve the plan. These choices preview that control.

1. Explore a finish

YOUR PLAN

Brick · Warm terracotta

Insulation 60 mmInsulation budget €7,500–€11,400

Planning range for the selected option.

Explore appearance choices
2. Compare the appearance
Adjust insulation and budget

Starting option: 60 mm

Custom material value
Wall U-value · W/m²K0.288Starting option 0.288
Insulation budget range€7,500–€11,400

Insulation: 60 mm

Finish budget

Editable assumptions, including VAT.

09 / PROPOSED APPLICATION · B2B2C WORKFLOW

How the renovation comes together.

A municipality starts the programme. One shared scope connects resident choices with independent bids and coordinated delivery.

The renovation workflowThe municipality initiates the programme. Homeowners move from discovery to verified results. NEST and NEST Planner connect their choices to independent professionals, contractors, banks and factories, under agreed rules. Dotted lines connect the roles. Homeownerthe clientIntermediaryB2B2C platformDoersqualified providersPublic sector 0Discover1Inquire2Define scope3Personalise4Choose5Follow6Verify results Scope + budgetChoices + progressResultsScoped workIndependent bidsAgreements NESTthe modelNEST PLANNERthe interfaceRules andagreements ProfessionalsContractorsBanksFactories STARTS THE PROGRAMME MunicipalityGridoperator
A shared plan connects resident choice with coordinated delivery.

WHO STARTS IT?

The municipality opens the door.

  1. Launch the neighbourhood programmeInvite residents, explain the purpose and bring the delivery partners together.
  2. Agree independent participation criteriaDefine how professionals and providers can qualify, with procurement arrangements agreed before bidding begins.
  3. Give delivery a clear ownerAn intermediary coordinates the plan. Professionals verify it; providers deliver the work. The municipality facilitates the start.

WHY THE SCOPE MATTERS

One scope. Competing offers.

Confirmed work
scope + homes + timing···Independent bids
price + dates + delivery···Resident chooses
a comparable offer

A contractor needs a credible demand promise before reserving capacity. Confirm participation, scope and timing, then invite competing offers for the same defined work.

Homeowners can compare what is included, when it starts and what it costs. Independent factories can also compete for the combined material orders.

The programme keeps competition open rather than handing the neighbourhood to one preferred supplier.

10 / NEXT STEP · PROPOSED PILOT

Let’s test it in
one neighbourhood.

The next step is to agree a neighbourhood, recruit residents and test the scope and bidding process together.

One neighbourhoodin the NetherlandsAbout 50 homeswith participating residentsEarly 2027target timing to agree
  1. Agree the location and partnersMunicipality, verification partner and independent providers.
  2. Test the scopes before scalingResident-authorised data, professional checks and comparable bids.
  3. Decide together whether to proceedReview resident trust, adviser time, provider participation and offer quality.
Discuss a pilot neighbourhood