Planning a home improvement project? A small kitchen extension is one of the most rewarding ways to increase space, light, and property value—especially in older UK homes. But before you dive in, it’s important to understand how long does it take to build a small kitchen extension, what’s involved, and how to get it right the first time.

This guide from KT5 Construction trusted builders in Surrey and London, walks you through every step of the journey—from initial approvals to final decoration.

What Counts as a Small Kitchen Extension?

A small kitchen extension is typically under 20m² and includes:

• • Rear extensions

  • Side return extensions

  • Compact wraparound designs

These extensions are popular in terraced and semi-detached homes where space is limited, yet the impact is transformational.

Timeline: How Long Does It Take to Build a Small Kitchen Extension?

Step 1: Design & Planning (2–12 weeks)

• • Initial consultation & design drawings

  • Planning permission or permitted development checks

  • Party Wall Notice (if applicable)

Most small kitchen extensions fall under permitted development, saving time—but you must still comply with building regulations.

Step 2: Pre-Construction (2–4 weeks)

• • Site clearance, skip hire, material orders

  • Setting out foundations and utilities

Step 3: Build Phase (8–16 weeks)

Average total time: 12 weeks of construction, with full project duration (planning to completion) around 4–6 months.

What Can Delay a Small Kitchen Extension?

While smaller projects are usually quicker to complete, delays can still occur due to:

• • Late material deliveries

  • Changes in design mid-build

  • Unforeseen structural issues

  • Weather disruptions (especially during groundwork)

At KT5 Construction, we proactively manage risks with weekly updates, careful scheduling, and strong supplier networks.

Why Homeowners Choose KT5 Construction

We specialise in designing and building beautiful kitchen extensions that feel tailored, functional, and effortless. Our services include:

• • Complete project management

  • Transparent timelines and fixed pricing

  • Local expertise across Surrey and London

  • Attention to detail at every stage

With a reputation for reliability and results, KT5 Construction is the builder homeowners trust to deliver outstanding kitchen extensions—on time, on budget, and stress-free.

Building Regulations & Safety Requirements

Regardless of size, your extension must:

• • Meet fire, electrical, and structural safety codes

  • Pass energy performance standards (Part L)

  • Include proper ventilation and damp-proofing

  • Stay within glazing limits (no more than 25% of the floor area without extra calculations)

We handle building control approvals and inspections so your project stays compliant from start to finish extensions.

Planning Tips from KT5 Construction

Top Tips to Stay On Track

• • Appoint a professional builder early

  • Lock in design decisions before the build starts

  • Choose local suppliers for quicker lead times

  • Set aside a 10–15% contingency fund

Popular Small Extension Features

• • Skylights for natural light

  • Bi-fold or sliding doors to connect with the garden

  • Open-plan kitchen and dining layouts

  • Utility space or cloakroom tucked in

FAQs: Small Kitchen Extensions

Q: How long does it take to build a 3x3m kitchen extension?

A 9m² extension can typically be completed within 10–12 weeks of construction.

Q: Do I need to move out?

Not usually. Many of our clients stay at home during the project, especially when the build is at the rear of the house.

Q: Does a small kitchen extension need planning permission?

Often no, but we confirm this for each client and help with Lawful Development Certificates for peace of mind.

Ready to Plan Your Small Kitchen Extension?

Take the first step with KT5 Construction today. Book a free consultation and let’s bring your kitchen ideas to life.