Here is what actually happens week by week, and what can move the timeline.
What is the full loft conversion timeline?
The build is only part of the journey. A realistic end-to-end picture looks like this.
If your conversion is permitted development, you can skip the planning stage, which is one of the reasons rear dormers and Velux conversions can move faster.
What happens week by week on site?
Every home is a little different, but in our North London loft conversions the build usually follows this rhythm:
- Weeks 1 to 2: Scaffolding goes up, the roof is opened, and the main structure and steels go in.
- Weeks 3 to 4: The dormer or new roof shape is built, made watertight, and windows are fitted.
- Weeks 4 to 5: Insulation, the staircase, first-fix electrics and plumbing are installed.
- Weeks 5 to 6: Plastering, then time for it to dry.
- Weeks 6 to 8: Second-fix electrics, decorating, flooring, and the final finish.
Dan and Niko handle our builds, and they keep the site tidy and the work moving so the weeks do not drift.
What can affect how long it takes?
A few things commonly stretch a timeline, and it helps to know them in advance:
- Planning permission: mansards, front dormers and conservation areas add roughly eight weeks for the application.
- Structural surprises: older roofs occasionally need extra strengthening once opened up.
- Bathrooms: adding an en suite means more plumbing, waterproofing and tiling time.
- Party wall agreements: these need to be sorted with neighbours before work starts.
- Weather: heavy weather during the roof-open stage can cause short delays.
- Finish choices: bespoke joinery or specialist tiling takes longer to fit.
How can you keep your loft conversion on schedule?
The biggest wins come before the first day on site. Confirm your layout early, choose your bathroom and finish before the build starts, and get any planning or party wall matters agreed in good time. When decisions are made up front, the team can work through the weeks without pausing for choices.
John plans the schedule at the start and keeps you updated as things progress, so you always know what is happening next. You can see the full range of options on our loft conversions page.
Kev Construct Ltd holds a 9.67/10 rating from 50+ verified Checkatrade reviews, built on projects delivered on time and to plan.
Get a free home visit and we will give you a realistic timeline for your loft.
FAQ
Can I live at home during a loft conversion?
Yes, most people do. Much of the early work happens through the roof from outside via scaffolding, and the main disruption is short, usually when the staircase opening is formed.
How long does a dormer loft conversion take?
A dormer typically takes around 6 to 8 weeks on site. Adding an en suite or premium finishes can push it towards the longer end.
Does planning permission add to the timeline?
Yes. If your conversion needs planning permission, allow roughly eight weeks for the decision before the build can be scheduled. Permitted development projects avoid this wait.
Want a realistic schedule for your own loft? See how we work on our loft conversions page, then book a free home visit and we will map out your timeline in writing.
