Permit before the first spade goes in
An extension needs a building permit (Baubewilligung). We coordinate the architect, the structural engineer and the building application, and only schedule the start of work once the permit is legally binding.
House extensions in Zurich.
More space on an existing building — an extra room, a larger living area or more room for your business. We coordinate the architect, the structural engineer and the building application; we build the foundations, masonry, wall insulation and interior fit-out ourselves, with one site manager and fixed dates in the contract for work (Werkvertrag).
Three firm commitments.
Shell and fit-out from one company
Foundations, masonry, wall insulation, drywall, plumbing, tiling, flooring and painting are carried out by us; electrical work by a licensed electrical contractor, coordinated by us. One site manager, one invoice.
Transparent costs, dates in the contract
Our labour is listed item by item in the quote, with materials separate. Planning, structural engineering, fees and scaffolding appear as separate items. The start date and handover date are set out in the contract for work.
The plot decides what an extension may be.
Before floor plans and materials, there is another question: what does the plot allow? How large an extension may be and how close it may come to the neighbouring boundary follows from the municipality's building and zoning regulations (Bau- und Zonenordnung) — permitted floor area (Ausnützung), boundary and building distances, heights. Once this framework is clear, the structure and the connection to the existing building follow: foundations and ground conditions, load transfer, a new opening in the existing external wall, and connections for water, waste water, electricity and heating. The architect and the structural engineer, whom we coordinate, resolve these questions before construction starts. If the permit comes with conditions that change the project, you receive a supplementary quote with a price — work only goes ahead once you have approved it.
Does an extension need a building permit?
Yes. Under § 309(1)(a) of the Planning and Building Act (Planungs- und Baugesetz, PBG), ‘the construction of new or the structural alteration of existing buildings’ requires a building permit. In the ordinary procedure (ordentliches Verfahren), the project is staked out with profiles (Aussteckung or Baugespann, § 311 PBG) before it is publicly announced, the documents are available for public inspection for 20 days (§ 314 PBG), and the authority decides within two months of the preliminary review, or within four for new buildings and larger conversions (§ 319 PBG). The notification procedure (Anzeigeverfahren), without staking out, applies only to projects of minor importance that do not affect third-party interests entitled to appeal (§ 13 of the Building Procedure Ordinance, Bauverfahrensverordnung, BVV); the BVV names, for example, balconies and projecting or recessed parts of buildings (§ 14(b) BVV). For extensions, the City of Zurich cites the fast-track ordinary procedure (ordentliches Schnellverfahren) as an example, which usually takes about three months; the type of procedure is set by the district architects (Kreisarchitekt*innen) of the Office for Building Permits (Amt für Baubewilligungen). What may be built follows from the building and zoning regulations and the building rules in terms of permitted floor area, type of construction and use (§ 250 PBG). As a rule, construction may only begin once the permit is legally binding (§ 326 PBG). We coordinate the application with the architect and the structural engineer and schedule the start of work accordingly.
From the idea to handover.
Five steps — the permit sets the pace.
- 01
Site visit
Our chief engineer records the building, the plot, access and connections. We discuss what you want to create and, with the architect, clarify the framework set by the building and zoning regulations.
- 02
Fixed-price quote within 48 h
Our labour item by item, materials listed separately. Planning, structural engineering, permit fees and scaffolding appear as separate items.
- 03
Plans, structure, building application
The architect and the structural engineer prepare plans and calculations; we coordinate. The building application is submitted electronically; in the ordinary procedure the project is staked out and put on public display.
- 04
Construction
Once the permit is legally binding: site set-up, foundations, masonry, wall insulation and connection to the existing building, followed by installations and interior fit-out.
- 05
Acceptance and handover
Joint acceptance with a report and handover on the date set in the contract for work. 5-year warranty from acceptance.
What it costs.
What an extension costs depends on its size, the ground conditions, the construction and the standard of finish — there is no reliable flat rate per m²; the binding figure is set out in the quote after the site visit and planning. As a guide, our 2026 unit rates for labour (lower price segment, excluding VAT, materials extra): site set-up CHF 850 flat rate, strip foundations CHF 480 per m³, concrete foundations including formwork and reinforcement CHF 490 per m³, brick masonry CHF 95 per m², wall insulation CHF 38 per m², core drilling up to 120 mm for pipes CHF 220 each. Structural engineering, planning, permit fees, scaffolding and cranes are not included and are quoted separately. Travel is included in Zurich and the surrounding agglomeration. Guide prices for the interior fit-out:
New plasterboard wallCHF 58–78per m²
ParquetCHF 45–70per m²
Painting wallsCHF 18–25per m²
- On-site survey and advice
- Binding quote, item by item
- Waste and packaging from our work
- Pressure and leak test with report (plumbing)
- Site cleaning and broom-clean handover
- 5-year warranty from acceptance
Frequently asked questions.
What people ask us most often before an extension.
Does an extension need a building permit?
Yes. Under § 309(1)(a) PBG, a building permit is required for the construction of new or the structural alteration of existing buildings. For extensions, the City of Zurich cites the fast-track ordinary procedure (ordentliches Schnellverfahren) as an example, which usually takes about three months. The building authority decides which procedure applies.
How much does an extension cost in Zurich?
We do not give a flat rate per m², because size, ground conditions and fit-out vary too much. Our 2026 unit rates for labour: strip foundations CHF 480 per m³, brick masonry CHF 95 per m², wall insulation CHF 38 per m², site set-up CHF 850 flat rate — each excluding VAT and materials. Structural engineering, planning, fees, scaffolding and cranes are extra. The fixed-price quote is binding.
How long does it take until construction can start?
First come planning and structural engineering, then the permit procedure. The building authority checks the application for completeness within three weeks (§ 313 PBG) and then decides within two months, or within four for new buildings and larger conversions (§ 319 PBG). After the building decision there is a 30-day appeal period; as a rule, construction may only begin once the permit is legally binding (§ 326 PBG).
What is a Baugespann?
The staking out of the planned building with profiles. In the ordinary procedure, projects that can be shown in this way must be staked out before the public announcement (§ 311 PBG); the documents are then on public display for 20 days (§ 314 PBG). Anyone wishing to assert claims must request service of the decision within 20 days (§ 315 PBG). In the notification procedure (Anzeigeverfahren), no staking out is required (§ 13 BVV).
How close to the neighbouring boundary can an extension be?
This is determined by your municipality's building and zoning regulations and the cantonal building rules: permitted floor area, boundary and building distances, and heights (§§ 250 f. PBG). The values differ from zone to zone; the architect checks them for your plot before planning begins.
Who does the architecture and structural engineering?
An architect and a structural engineer whom we bring in and coordinate; if you already have an architect, we work with them. Planning and structural engineering costs are shown separately. We carry out the foundations, masonry, wall insulation and interior fit-out; electrical work is done by a licensed electrical contractor, coordinated by us.
Related:
What does it cost? Guide prices in 30 seconds.
Choose an area, choose a service, move the slider — you see the guide price for the labour straight away. Materials and VAT come on top; the fixed-price quote is binding.
Area
Service
Guide price for Painting walls · 40 m² wall area
CHF 720 – 1'000
CHF 18–25 per m²
Two coats, covering included (paint as materials extra)
- Labour only · materials extra · excl. VAT
- Budget range — not a binding total price.
Unit prices for the labour from our 2026 price list (lower price segment), excl. VAT. The higher figure applies in difficult conditions. Materials, disposal of strip-out material, crane, scaffolding and permits come on top. The guide price does not replace a site visit.
Let's talk about your project.
The consultation is free. You get a confirmation straight away, and we call you back within one hour (Mon–Fri 08:00–18:00).