Who is obliged: owner or tenant?
The GModG places the duty to install building automation and lighting control on the owner of the building. This also applies if the building is wholly or partly let. Tenants have no retrofit duty of their own under § 56.
For landlords this means: they must initiate the work – and usually need access to the let areas to do so. Talking to tenants early about the schedule and construction phases avoids conflict later.
Who bears the costs?
The GModG does not say who bears the cost of the measures. That follows from the lease and tenancy law – for example from the provisions on modernisation, maintenance and service charges. Have this checked legally for your leases.
Economically, lighting control is often an argument for both sides: the lighting's electricity consumption falls, and the building meets the legal requirements – a point increasingly asked about when letting and selling.
Energy performance certificate: what changes from 2027
From 1 January 2027, new rules apply to energy performance certificates for non-residential buildings. Among other things, they introduce efficiency classes from A to G, based on the calculated energy demand to DIN/TS 18599. The installed lighting is part of this calculation.
Landlords must still present the energy performance certificate at the viewing at the latest. Efficient, controlled lighting lowers the calculated energy demand – modernising the lighting before the next certificate means starting from better figures.
Steps for landlords
- Determine the rated output of heating, air conditioning and ventilation: more than 70 kW?
- Assess the lighting: can it be controlled, dimmed and divided into zones?
- Agree the work with tenants: schedule, access, construction phases.
- Settle the concept, budget and funding before awarding contracts.
- Implement, commission and document – by 31 December 2029 at the latest.
Whether your building is affected is shown by the GModG check in the guide Buildings over 70 kW.
ConsultationLet's talk about your project.Lighting calculation and quotation from the manufacturer.One contact for the lighting
TRiALED takes care of the lighting in let commercial property completely – from the survey through lighting design, luminaires and sensors to installation, even while tenants carry on working. Which solutions suit offices, halls and retail space is shown in the guide Lighting commercial property.
Frequently asked questions
How does the GModG affect landlords of non-residential buildings?
The owner is obliged: if the heating, air-conditioning or ventilation system has a rated output of more than 70 kW, building automation and automatic lighting control must be installed by 31 December 2029 – even if the building is let.
Does the tenant have to install the lighting control?
No. Under § 56 GModG the owner is obliged. What tenants have to contribute or tolerate is governed by the lease and tenancy law.
Can the landlord pass the costs on to tenants?
That is governed not by the GModG but by the lease and tenancy law. Have this checked for your leases.
Does the duty also apply if only part is let?
Yes. What matters is whether it is a non-residential building with a rated output of more than 70 kW – not who uses it.
