On this page
- Price indications and what to compare
- Items to include in the quote
- Allow for materials and labour
- Access can make a significant difference
- How do we avoid unclear extra costs?
- Compare dimensions, doors and daylight
- Foundations and connections to the existing home
- What do shell-only and fully finished mean in your quote?
- From preparation to handover
Prices shown as “from” are indicative starting amounts for the stated scope. Your quotation specifies materials, labour, VAT and additional work.
Price indications and what to compare
| Work | Indicative starting price | Scope and assumptions |
|---|---|---|
| Extension: initial budget indication | From € 2,200 per m² | Indicative market price; specify VAT, foundations, demolition, services and finishing explicitly. |
| Worked example: 20 m² | € 44,000–70,000 | 20 times the range above; not a fixed total price. |
Market estimates consulted on 2 October 2026. These are not fixed Multi Concurrent rates. Your project quote specifies the price, VAT and included work.
Items to include in the quote
Design, structural calculations, permit support, foundations, floor, facade, roof and window and door frames form the basic building package. Also discuss the opening into the house, steelwork, services, finishing, scaffolding or lifting, waste disposal and reinstating the garden.
Allow for materials and labour
A timber structure, masonry facade or large sliding doors require different materials and work. Ask which products are included and which items are provisional sums. A provisional sum is not a confirmed price for your final selection.
Access can make a significant difference
Open access from the rear offers different options from moving materials through the house. Crane positioning, temporary traffic measures and storage space need advance consideration.
How do we avoid unclear extra costs?
We record the agreed basis, including what falls outside the scope. If a choice or unforeseen condition affects the cost or schedule, we agree this before carrying out the additional work.
Compare dimensions, doors and daylight
A larger extension needs more than extra floor area. Facades, roof, foundations and finishes also change. Large glazed openings and rooflights affect both materials and junction details. Request quotations for the same dimensions and window and door layout to distinguish specification differences from price differences.
Foundations and connections to the existing home
Have the required foundations assessed for the site. A pile or square-metre rate says little about the whole job without a design. Include the opening to the house, temporary provisions, repairs to existing floors and any service changes. These often explain significant differences between a shell offer and a complete extension.
What do shell-only and fully finished mean in your quote?
Define the scope precisely. Does it include electricity, heating, ventilation, plastering, painting and flooring? Is the existing home made good after the opening is formed? Agree who supplies, measures and installs products. List allowances and exclusions so later decisions and their price implications are clear.
From preparation to handover
Initial discussion
Discuss your requirements, intended use, address and budget.
Site survey
Assess the property, access and connections to the existing building.
Design
Agree the layout, natural light, appearance and materials.
Structural design
Design the foundations, opening and supporting structure.
Permits
Check the location and design through the Omgevingsloket.
Quote
Discuss the scope, provisional allowances, exclusions and price.
Preparation
Arrange the schedule, site logistics, deliveries and protection.
Foundations
Build the foundations in accordance with the project-specific design.
Shell structure
Construct the floors, walls, windows, doors and roof.
Installations
Coordinate electricity, water, heating and ventilation.
Finishing
Complete plastering, painting and floor finishes.
Handover
Inspect the work and agree how any outstanding items will be addressed.
Frequently asked questions
Is the price on this page a quote?
No. An estimate or worked example is for initial planning. The property, materials and agreed scope determine your quote.
What should I include in a quote request?
Describe the work and include the town, postcode, photographs, dimensions and any available drawings. Add your preferred start period. Larger projects need a site visit to establish the scope and price.
Do I need a permit?
This depends on the work, the address and local rules. Check your plan through the Dutch Omgevingsloket and have structural alterations assessed in advance. Work that does not need a permit must still comply with applicable building rules.