Aanbouw 24/7 · since 2010

    Home extensions made to fit.

    We design and build home extensions, second-storey additions, bay windows and conservatories throughout the Netherlands. You get clear advice, a fixed price upfront and up to 10 years of structural warranty.

    No obligation · Specialist response within 24 hours

    Modern Dutch home extension with large sliding glass doors
    ↑ Extension with sliding doors2025
    1,200+

    Projects

    15

    Years of craftsmanship

    4.8

    Client rating

    10

    Year warranty

    • BouwGarant certified
    • 10-year structural warranty
    • Fixed price upfront
    • Response within 24 hours

    Selected work

    Recently completed extensions

    Kitchen extension with rooflight

    Extension · Haarlem · 24 m²

    Kitchen extension with rooflight

    Living room with steel doors

    Rear extension · Utrecht · 32 m²

    Living room with steel doors

    Timber garden office extension

    Extension · Amersfoort · 18 m²

    Timber garden office extension

    Brick rear extension with kitchen-diner and sliding doors at dusk

    Extension · Eindhoven · 28 m²

    Kitchen-diner extension with sliding doors

    Open-plan kitchen extension with marble island and bi-fold doors

    Extension · 's-Hertogenbosch · 36 m²

    Open-plan kitchen extension

    White rendered rear extension on a Dutch terraced house

    Rear extension · Rotterdam · 26 m²

    Rendered rear extension

    Steel-frame glass conservatory attached to a classic Dutch brick villa

    Conservatory · Leiden · 22 m²

    Steel-frame glass conservatory

    Dark zinc-clad rear extension with sedum green roof on a 1930s home

    Extension · Groningen · 30 m²

    Zinc-clad extension with sedum roof

    Cost estimate

    A realistic guide price, upfront.

    Fill in four fields and immediately see a realistic budget range based on comparable projects. No obligation and no email required upfront.

    Read more about costs →

    Process

    From first idea to handover in five steps.

    1. 01

      Request & advice

      Tell us about your plans online or by phone. We call back within 24 hours with first advice.

    2. 02

      Site visit & design

      A specialist visits, measures the space and discusses materials, layout and feasibility.

    3. 03

      Fixed-price quote

      You receive a detailed quote with a clear fixed price and scope.

    4. 04

      Permit & planning

      When needed, we coordinate the permit process and agree a practical construction schedule.

    5. 05

      Build & handover

      Our own craftspeople build the extension and walk through the result with you at handover.

    Client stories

    What clients tell us.

    Read how homeowners throughout the Netherlands expanded their homes with an extension, second storey or conservatory.

    • We twijfelden lang of een aanbouw op ons rijtjeshuis wel haalbaar was. Na het adviesgesprek bleek het gewoon te kunnen. De doorbraak naar de woonkamer was spannend, maar binnen twee dagen dicht. In totaal 9 weken van start tot oplevering, precies zoals afgesproken.

      Familie De Vries

      Haarlem · Aanbouw 18 m²

    • De stalen pui was voor ons doorslaggevend. Aanbouw 24/7 heeft het hele traject begeleid, inclusief vergunning en constructieberekening. De planning schoof één week op door het weer, maar daar werden we op tijd over geïnformeerd. Eindelijk een woonkamer met licht.

      Sophie van Dijk

      Utrecht · Uitbouw woonkamer 24 m²

    • Aanbouw van 16 m² voor een open keuken met schuifpui naar de tuin. We hebben zelf de vloer en het schilderwerk gedaan, dat scheelde behoorlijk. De ruwbouw stond er in 5 weken. Communicatie via een vast aanspreekpunt, dat werkte heel prettig.

      Lisa Bosman

      Amersfoort · Keuken-aanbouw 16 m²

    No obligation & response within 24 hours

    Ready to extend your living space?

    Tell us about your plans. A specialist will contact you within one working day with tailored first advice.

    Frequently asked questions

    Answers to the questions we hear most.