Planning your development Planning your project

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This article, Planning your development, was last updated on 31 March 2008 and is now out of date and held in our online archive for reference. Explore our latest Home & garden articles.

Working out the time it takes to do specific jobs is difficult without a specific quote. 

For example, decorating a 5 x 5m room might only require an undercoat of paint, then one topcoat, which could be done in a day. Or, it might be that the walls need to be sanded down to remove previous paint, then cracks filled, two undercoats applied, followed by three colour coats of paint - which could all take a full week.

Our guideline estimates how long a project might take from planning to completion on an average three-bedroom detached home. But every project is different, so you'll need to confirm these timings with your contractors and your local authority if you're seeking planning and building regulations approval.

Planning your home improvement
Project Planning Lead time from
order to deliveryb		 Average time to
carry out project
Extensionsa
Two-storey 24 weeks 3 months–1 year 12 weeks
One-storey 16 weeks 3 months–1 year 6 weeks
Garage 16 weeks 3 months–1 year 3 weeks
Conservatory 12 weeks 6 weeks 1–2 weeks
Basement 12 weeks 6 weeks 2–4 weeks
Conversions*
Loft 16 weeks 12 weeks 2–8 weeks
Garage 10 weeks 2 weeks 2–4 weeks
Basement 16 weeks 4 weeks 1 week
Additions
Garden building 4 weeks 4 weeks 4 weeks 1–10 days
Kitchen 4 weeks 0–6 weeks 3–10 days
Bathroom 4 weeks 0–6 weeks 3–10 days
Replacements
Windows 6 weeks 2–6 weeks 1–2 days
Doors 1 week 0–2 weeks 1–2 days
Wiring 2 weeks N/A 2–3 days
Central heating
System 2 weeks 1 week 1–2 days

Table notes

  1. Assumes planning permission/regulations required. If these aren’t necessary, planning time can be halved
  2. Includes time to book professional help and materials
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