“How long will it take?” is the second most common question we get asked in Redditch, right after “how much will it cost?”. The honest answer depends on scale, complexity, planning and weather. Here is a realistic breakdown of how long each type of extension actually takes from first sketch to final handover.
The three phases of every extension
Every extension has three phases: design and planning, construction, and fit-out. Underestimating any of them is the single biggest reason projects overrun.
Phase 1: Design and planning (6–16 weeks)
- Measured survey and initial sketches: 1–2 weeks
- Planning drawings and structural design: 2–4 weeks
- Planning application decision: 8–10 weeks (statutory)
- Building Regulations approval: runs alongside
If your extension falls under Permitted Development, you can skip the 8–10 week planning wait entirely and move straight to Building Regs.
Phase 2: Construction (varies by extension type)
Once we break ground, typical build times we see across Redditch and the West Midlands look like this:
- Single-storey rear extension (20–30 m²): 10–14 weeks
- Wrap-around extension (30–45 m²): 14–18 weeks
- Two-storey rear extension: 16–22 weeks
- Loft conversion with dormer: 8–12 weeks
- Full basement conversion: 16–24 weeks
Phase 3: Fit-out and snagging (2–4 weeks)
Kitchens, bathrooms, decoration, floor coverings and the final snag list. This is often where clients get impatient because the space looks “nearly done” from week 10 but is not habitable until week 14. Every trade needs its time.
What actually slows an extension down
Weather
Once the shell is weathertight, internal work continues year-round. But if we are pouring foundations in a wet January, expect a week or two of delays. We plan starts around expected weather where we can.
Planning permission decisions
A refused application at week 8 pushes you back 3–4 months while you appeal or resubmit. Our approach: pre-application advice with Redditch Borough Council before we submit anything contentious.
Utility connections
New drainage connections or electricity supply upgrades can take 6–12 weeks to be scheduled by the utility company. We book these as early as possible.
Structural surprises
Older Redditch homes sometimes reveal unexpected structural conditions once the walls come off. Our fixed-price quotes include a modest contingency, but genuinely unforeseen work is discussed openly before it happens.
Total realistic timeline: single-storey rear extension in Redditch
From your first phone call to the day you host guests in your new kitchen, budget on:
- Best case (Permitted Development): 18–22 weeks
- Typical (with planning): 26–32 weeks
- Worst case (planning appeal or refused first-time): 40+ weeks
How CK Construction keeps builds on programme
Because every trade is on our own team, we schedule internally. There are no delays waiting for a sub-contractor plumber to fit us in between other jobs. Our project managers publish a week-by-week programme at the start of the build and update you every Friday. If we slip on any week we tell you why and how we will recover.
Ready to talk about your extension?
Contact CK Construction for a free initial consultation. We cover Redditch, Birmingham, Solihull and the wider Warwickshire area. Call 01527 521835 or use our contact form.
Serving homeowners across Redditch, Worcester, Malvern, Birmingham and the wider region.