Building and operating·FindingConfirmed

Companies that apply for a renovation or extension permit are more than twice as likely to apply for an environmental permit

Of the 2,892 companies with a renovation or extension permit application, 12.4% also had an environmental permit application within nine months, against 5.3% among similar companies. The source only covers 671,780 companies with their registered office in Flanders; the comparison stays within that group. Measured year by year, the link held in every year since 2018.

Environmental permit within nine months of the event

Both measurements combined · 2,892 companies

After a renovation or extension permit application12.4%

Similar companies5.3%

2.3×

as often as among similar companies.

95% interval: 2.1× to 2.6×
Companies: 2,892
Measurements: 2, independent

Source: Hunch Lab, cohort study within 671,780 companies with their registered office in Flanders. Compared within sector, size and age, with companies active in the same period.hunchleads.com/en/lab

Does it hold up?

Each measurement uses different companies and a different period. A link only counts if it shows up in both.

Measurement	Period	With the event	Similar	Factor
Measurement 1	event Jan–Jun 2025, outcome Jul 2025–Mar 2026	13.6%	5.7%	2.4×
Measurement 2	event Jul–Dec 2025, outcome Jan–Sep 2026	11.3%	5.0%	2.3×

Also measured year by year, since 2018

Measurement	Period	With the event	Similar	Factor
2018	application in 2018, outcome the following year	12.6%	1.6%	8.0×
2019	application in 2019, outcome the following year	11.1%	1.7%	6.5×
2020	application in 2020, outcome the following year	13.2%	2.0%	6.4×
2021	application in 2021, outcome the following year	13.6%	2.1%	6.6×
2022	application in 2022, outcome the following year	12.3%	2.2%	5.6×
2023	application in 2023, outcome the following year	12.7%	2.2%	5.9×
2024	application in 2024, outcome the following year	14.7%	2.1%	7.2×

When does it happen?

Cumulative share by month after the first event. Half of the cases in the first year occur within 4 months.

By sector

The sectors with the most companies in the test, both measurements combined.

Sector	Companies	With the event	Similar	Factor
Real estate	705	12.9%	6.3%	2.0×
Construction	351	14.5%	8.3%	1.7×
Wholesale and retail	213	12.7%	4.4%	2.9×

By size class

Full-time equivalents from the latest annual accounts. Employer: staff registered with the NSSO, headcount unknown.

Size	Companies	With the event	Comparable	Factor
No staff	1,617	6.4%	2.7%	2.4×
Employer, headcount unknown	920	16.5%	6.5%	2.6×

How often does this happen?

Belgian companies with the event, per month, over the last twelve complete months.

Renovation or extension permit257 a month on average

Environmental permit884 a month on average

More on renovation or extension permit

4 other findings

FindingWith the eventSimilarFactorResult

Companies that apply for a renovation or extension permit are more than three times as likely to file another type of planning applicationBuilding and operating11.3%3.3%3.4×Confirmed Companies that apply for a renovation or extension permit are almost three times as likely to apply for a new-build permitBuilding and operating11.3%4.3%2.6×Confirmed Companies that apply for a renovation or extension permit are 1.6 times as likely to open a new establishmentBuilding and operating3.3%2.1%1.6×Confirmed Companies that apply for a renovation or extension permit are no more likely to receive de minimis aidBuilding and operating11.9%11.0%1.1×No link

Technical note

Methodology

Design: Retrospective cohort study
Population studied: 671,780 companies with their registered office in Flanders
Comparison group: Companies without the event that had another publication or event in the same entry period (active group), from the same stratum: NACE section, size class and age class; indirect standardisation
Cohorts: event Jan–Jun 2025, outcome Jul 2025–Mar 2026; event Jul–Dec 2025, outcome Jan–Sep 2026
Observed and expected: 359 cases, 154 expected
Factor (95% interval): 2.3× (2.1× to 2.6×)
Multiple testing: q < 0.001 (Benjamini-Hochberg)
Second measurement: p < 0.001
Other comparison groups: economically active companies 4.0× (3.6× to 4.4×); all companies 5.6× (5.1× to 6.3×)
Absolute difference: 7.1 percentage points; following 14 companies with the event yields one extra case
Size of the groups: active 67,044, economically active 214,185, all 671,780 companies
Strata: 88 strata of at least 300 companies (section × size × age; smaller strata merged)
Data up to: September 2026

Cite this findingFree to reuse with attribution (CC BY 4.0).

Hunch Lab (2026). Companies that apply for a renovation or extension permit are more than twice as likely to apply for an environmental permit. Data up to September 2026. https://hunchleads.com/en/lab/vg-uitbreiding-vg-exploitatie

Figures for this finding (CSV)

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