ISDE subsidy
This page is intended for installation companies, consultants and other professionals who guide homeowners in applying for the ISDE (Investment subsidy for sustainable energy and energy savings) for energy-efficient ventilation systems. The subsidy for ventilation amounts to a fixed amount of €400 and is only available if the ventilation measure is combined with one or more insulation measures. The installation must be carried out entirely by an installation company; DIY is not allowed and the ventilation system must meet a number of conditions.
Key points at a glance
- Fixed subsidy amount: €400 (one-off per homeowner/house for ventilation).
- Only for owner-occupiers (ISDE energy-saving component).
- Ventilation combined with at least one ISDE insulation measure (within 24 months).
- Ventilation system must be installed on or after 1 January 2026.
- Apply within 24 months of installation of the ventilation system.
- Installation should be done entirely by a (construction) installation company; do not do it yourself.
- Ventilation system must be new (no second-hand/used products).
Main conditions (RFO)
The ventilation system must be installed on or after 1 January 2026. The homeowner first has the system fully installed by a recognised (construction) installation company and only then applies for the subsidy. Self-installation is expressly not allowed. The subsidy only applies to existing homes. These are homes with a year of construction before 1 January 2019, or homes for which it can be shown that the environmental permit was applied for before 1 July 2018. The ventilation subsidy application must be submitted within 24 months of the installation of the ventilation system. In addition, a combination requirement applies; the subsidy for ventilation is only possible if this measure is combined with one or more eligible insulation measures. Again, the subsidy for ventilation must be applied for within 24 months of the implementation of the insulation measure; this may be done at the same time as the application for insulation.
Which ventilation systems are eligible?
RVO distinguishes 3 types of eligible ventilation systems. The conditions differ for each type. In summary:
- Central CO₂-controlled extraction fan: minimum capacity > 125 m³/h and at least 2 CO₂ sensors.
- Central balanced ventilation with heat recovery (CHP unit): minimum efficiency 85% and minimum capacity 125 m³/h (tested in accordance with EN13141-7:2021).
- Decentralised balanced ventilation with heat recovery (recuperative heat exchanger): minimum efficiency 80%, tested in accordance with EN13141-8:2022, minimum capacity 80 m³/h and simultaneous supply/exhaust in the unit.
Please note that the RFO application uses a report code (product code) to show that the system meets the requirements.
Reporting code and reporting code list: what should you as a professional arrange?
- Appliances with notification code have been tested by RFO against the requirements in the scheme and provide clarity/security for consumers and installers.
- The reporting code list is updated periodically and is also used in the application form (eLoket).
- Make sure the reporting code is mentioned on the invoice towards the homeowner (practical: this prevents delays in the subsidy application).
For manufacturers/suppliers, notification is via the regular RFO procedure; from 1 January 2026 via e-mail to DEW@RVO.nl with ventilation notification form and technical documentation (including brand, type, category, capacity, EPREL ID, energy label, sound power, energy consumption, WTW efficiency).
Practical checklist for installers and consultants
- Check whether the customer is an owner-occupier and whether the property falls within the RFO conditions (existing construction).
- Determine with the customer which insulation measure(s) are covered by ISDE and guarantee the 24-month period versus ventilation.
- Choose a ventilation system that meets the appropriate type and (where applicable) performance requirements (capacity, efficiency, CO₂ sensors).
- Record: quotation, invoice, proof of payment, execution date, product details and report code.
- Put the report code and relevant product description clearly on the invoice.
Frequently asked questions about the ISDE subsidy
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As a private individual, can you insulate and install the (ventilation) system yourself, or must it be done by a company to claim the subsidy?
No. DIY is not possible; this must always be fitted by a company.
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The subsidy does not apply to housing associations as it is not for the business market?
True a business application cannot for ventilation.
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Suppose: on 1-2-2024 you applied for an ISDE insulation measure; on 1-1-2026 you had a ventilation system installed; on 1-1-2027 you apply for ISDE ventilation. What if you are within 2 years term of ISDE ventilation, but no longer within 2 years for the condition measure (ISDE insulation)?
The date of ISDE ventilation is leading: the subsidy application must be made within 2 years of the installation of the ventilation unit. That application will consider whether an ISDE insulation measure was carried out in the previous 2 years.
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Is it possible for an end user to still purchase a CO₂ sensor on a residential fan that was already purchased within the last 2 years?
No, it must be a complete purchase of the listed parts: ventilation unit including 2 CO₂ sensors.
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Does the burden of proof for declaration of properties lie in EPREL or does it lie in supplying measurement reports?
Both: EPREL contains the relevant magnitudes, with reports as substantiation. RFO can request those reports; they are kept confidential.
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We manufacture ventilation heat pumps. Do we still need to apply for a separate notification code for the ventilation part?
The starting point is: one or the other; you cannot apply for both techniques. As a rule, the ISDE subsidy for the heat pump/heat pump boiler will be higher.
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Should the request be made at item number level, or is it also allowed at model level?
At model level (initial estimate), provided test data match.
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How do we register combinations, such as a mechanical ventilation system with two CO₂ sensors? What is the best way to register a system with 2 CO₂ sensors? What is meant by additional burden of proof?
This depends on the system. If it is a unique type of system that is only marketed with that CO₂-sensor combination, then a separate notification code. Often it is a standard product with optional CO₂ sensors: then only notify the ventilation system and make sure the invoice clearly states that CO₂ control is present.
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As an installation company, does it require specific accreditation or certification to install these subsidised systems?
No there is no additional certification or accreditation required as an installation company to install any of the systems eligible for the ISDE scheme. Most importantly, residents are not allowed to install the system themselves.
