How long you will be without a bathroom, how long the kitchen will be out of use and when the scaffolding will finally come down: those are the questions that shape daily life during a renovation. Yet contractors rarely give a hard number, and rightly so: a timeline depends on the scope of the work, the number of tradespeople who have to follow one another, drying times, delivery times and sometimes a permit. This article gives realistic ranges per job, explains why schedules overrun and what you can do yourself to keep the timeline short and predictable. The times are based on common practical experience and apply to an average home; your contractor will give you a tailored schedule.
Three kinds of time: execution, lead time and preparation
Before you compare figures, it helps to keep three concepts apart. The execution time is the number of days on which someone is actually working. The lead time is the period from the first to the last working day, including days on which nobody comes because something has to dry or because the next tradesperson can only come later. The preparation time comes before that: comparing quotes, ordering materials, applying for a permit. A bathroom with five working days of execution easily has a lead time of two to three weeks, preceded by six to ten weeks of preparation in which tiles, sanitary ware and a schedule with the tradespeople are fixed. If you ask a contractor "how long will it take", you will often be told the execution time; so ask explicitly about the lead time and the date on which you can live normally again.
Timelines per job
The table below gives the usual range for an average situation. The lower end applies to a simple job with one or two tradespeople and no surprises; the upper end to a complete overhaul in which pipework, electrics and finishing are renewed as well.
| Job | Execution | Lead time | What determines the time |
|---|---|---|---|
| Replacing a central heating boiler | Half a day to one day | One day | Same location and connections, or relocation with new pipework and flue |
| Renovating a toilet | 2 to 4 days | 1 week | Tiling and drying time of adhesive and grout, concealed cistern or not |
| Renovating a bathroom | 5 to 10 working days | 2 to 3 weeks | Demolition, pipework, plastering, waterproofing, tiling, grouting, sealing, sanitary ware; each with its own drying time |
| Fitting a kitchen | 2 to 5 days | 1 to 2 weeks | Assembly only, or also rerouting pipes and electrics, new floor and tiles |
| Plastering per room | 1 to 3 days | 1 to 2 weeks including drying | Layer thickness: rule of thumb roughly one day of drying time per millimetre before painting |
| Interior painting of a home | 3 to 7 days | 1 to 2 weeks | Number of coats, drying time between coats, repairing the surface |
| Exterior painting of a terraced house | 3 to 6 days | 1 to 3 weeks | Weather: dry, above the paint's minimum temperature, no dew |
| Prefab dormer | 1 day to install | 1 to 2 weeks including finishing | Production in the factory beforehand usually takes a few weeks |
| Traditional dormer | 3 to 5 days | 2 to 3 weeks | Built on site, depending on the weather and interior finishing |
| New roof | 1 to 5 days | 1 to 2 weeks | A flat roof is quicker than tiles; insulation and roof windows add time |
| Extension | 6 to 12 weeks | 3 to 5 months including preparation | Foundations, shell construction, roof, window frames, installations, finishing; often a permit |
For a renovation that requires a permit, add the municipality's decision period: the regular procedure under the Omgevingswet (Environment and Planning Act) takes eight weeks and can be extended once by six weeks. Also allow time to have drawings and calculations made. Whether your job requires a permit is explained in When do you need a permit for a renovation.
Why a schedule overruns
Almost every renovation that takes longer than planned gets stuck on one of the following five causes.
Drying times
Concrete, cement screeds, plasterwork, tile adhesive, grout and sealant all need time before the next step can begin. A sand-cement screed has to dry for weeks before parquet can go on it; plasterwork has to be dry before the painter starts; a freshly sealed shower must not get wet for a day. These days are often missing from the schedule, yet they determine when you can shower again.
Delivery times
Kitchens, made-to-measure window frames, prefab dormers, special tiles and sanitary ware have delivery times of a few weeks to a few months. A tradesperson who is ready to go but waiting for a window frame costs you lead time. So order everything before the first working day is scheduled, and check deliveries on arrival for damage and completeness.
Multiple trades
A bathroom needs a demolition worker, a plumber, an electrician, a plasterer, a tiler and someone to do the sealing. Each of them has their own diary. A main contractor who manages them can schedule them tightly one after another; if you hire them separately yourself, gaps of days easily appear between the successive steps. Which form of organisation suits your job is explained in Contractor, building firm or handyman business: who do you need.
The weather and the construction holiday
Exterior painting, roofing, bricklaying and foundations depend on dry weather and on temperatures above the minimum for paint, mortar and concrete. A wet week can easily push an outdoor job back by two weeks. Also take into account the bouwvak (the collective construction-industry summer holiday) and the Christmas period, when many firms close for a few weeks.
Surprises and changes
A rotten joist under the bathroom floor, a pipe in an unexpected place, asbestos-containing material or a floor that turns out not to be level: every surprise takes time to assess, price and resolve. The same goes for wishes you add during the work. How to deal with that without the schedule and budget going off the rails is covered in Extra work during a renovation: rules, prevention and what you may refuse.
How to keep the lead time short
- Ask for a schedule with milestones rather than just a start date: when is demolition finished, when are the pipes done, when does tiling start, when is the handover. That way you can see straight away where things are slipping.
- Make all decisions in advance. Choice of tiles, tap, position of sockets, colour of the grout: every decision that still has to be made during the work brings the tradesperson to a halt.
- Order early and check on delivery. Make sure materials with long delivery times have arrived before the work starts.
- Clear the work area. Empty the room, cover the floors, arrange parking space and a spot for the skip. Half a day of clearing up by the tradesperson is half a day of your lead time.
- Agree in writing what happens if the work overruns. An agreed completion date with a reasonable arrangement for delays attributable to the contractor prevents disputes. Industry terms and conditions for consumers include standard provisions for this.
- Plan around the seasons. Outdoor work in spring and late summer, indoor work in winter; preferably no bathroom in the week before the construction holiday.
On VerbouwPro you post your job free of charge and tradespeople from your region who have capacity at short notice respond. In the conversation, ask not only about the price but also about the lead time, the start date and how the tradesperson coordinates with other trades. How to approach the full preparation is explained in How to prepare for a renovation.