Facade insulation: cost, benefits and the right moment

Which methods exist — and what do they cost?

Guide prices from Lidstein project practice, 2026; comparable ranges are published by co2online and the German consumer advice centres.

Why does the scaffolding decide the economics?

Scaffolding, site set-up and rendering are a large share of any facade job — and they cost the same whether you insulate or not. If the facade is due anyway, insulation only adds the material and its installation. That is the coupling principle: repainting without insulating is the most expensive option — you pay for the scaffolding, forgo the energy savings, and under the GEG often have to retrofit anyway.

What does the GEG require?

The German Building Energy Act generally requires current U-values whenever more than 10 % of a building element is renewed — new render, for example. Exceptions exist for pure repainting and some listed buildings. In practice: new render = plan the insulation with it, or risk non-compliance and double work.

Which subsidies exist in 2026?

• BEG individual measures (BAFA): 15 % grant plus 5 % iSFP bonus — up to 20 % on max. 30,000 € eligible cost per dwelling per year (60,000 € with iSFP).
• Tax relief § 35c EStG: alternatively 20 % over three years — not combinable with the grant.
• Prerequisite: apply before contracting; terms at bafa.de.

What do you gain beyond heating costs?

• Comfort: warm wall surfaces instead of draughts and cold radiation.
• Mould protection: higher surface temperatures defuse thermal bridges and condensation.
• Property value: a better energy class is measurably worth money at sale.
• Summer heat protection: insulation works in both directions.

Within a gut renovation, facade insulation belongs to the building-envelope package — at Lidstein planned and built by one team, at a fixed price on request.

Frequently asked questions

What does facade insulation cost per square metre?

An external thermal insulation composite system (ETICS) costs 180 to 350 euros per square metre of facade in 2026, including scaffolding and render. For a detached house with 150 square metres of facade that means roughly 27,000 to 52,000 euros before subsidies.

How high are the German subsidies?

Under BEG individual measures: a 15 percent grant, plus a 5 percent bonus with an individual renovation roadmap (iSFP) — up to 20 percent on a maximum of 30,000 euros of eligible cost per dwelling per year (60,000 with iSFP). As of early 2026; check current terms with BAFA.

Do I have to insulate when renewing the facade?

Often yes: if more than 10 percent of the facade area is renewed — for instance with new render — the German Building Energy Act (GEG) generally requires current insulation values. If scaffolding is up anyway, plan the insulation in.

When does insulation pay off?

External walls account for a substantial share of heat loss in uninsulated buildings. With subsidies, and coupled to facade work that is due anyway, payback typically falls within 10 to 20 years — plus comfort, mould protection and property value.