ig. design & interiors

Renovation Cost Guide

A home renovation is one of the most significant investments you will ever make. Done well, it transforms not just the fabric of a building but the way you feel within it — the quality of light in the morning, the ease of moving through a space, the quiet satisfaction of a home that works exactly as it should.

This guide has been created to bring clarity and confidence to that process. It is a working tool, not a brochure — designed to help you build a realistic picture of costs before you speak to contractors, brief your design team, or commit to a programme of works.

How to use this guide

01.

Choose your finish tier

Select Standard, Premium or Luxury at the top of the page. Each tier reflects a different level of specification, materials and craftsmanship. Read the tier descriptions — they are written to help you self-select honestly.

02.

Work through each room

Tap any room to expand it. Enter the actual size in m², set the number of rooms of that type you are renovating, and tick or untick individual elements to match your project scope. Costs update instantly.

03.

Add extensions if applicable

If your project includes a single-storey extension, double-storey extension or loft conversion, enter your m² figures in the relevant sections. Windows, doors and fenestration are not included in extension rates and must be budgeted separately.

04.

Set your region & contingency

In the project summary at the end, choose your region to apply a local cost adjustment, and select a contingency level. Your VAT, regional adjustment and contingency are then shown as clear, separate lines building to an estimated total.

05.

Use it as a conversation starter

This guide gives you a well-informed starting point. It is not a quote. Always obtain a minimum of three contractor quotes before committing to any works — and engage your design team early. The decisions made at the beginning of a project are the ones that determine its outcome.

All figures are indicative guide prices inclusive of labour and materials unless otherwise stated, based on UK national averages verified against BCIS/RICS, Checkatrade, the Federation of Master Builders and specialist trade publications (2025). All prices throughout this guide are quoted exclusive of VAT, which is charged at the prevailing rate (currently ) and must be added to the figures shown. Regional adjustments are applied in the project summary.

Architectural Lighting & Home Automation

These specialist categories require individual quotation and are not included in the room cost tables above. Costs vary significantly by system complexity, number of circuits, and installer. The ranges below are indicative guides based on publicly available UK pricing from authorised dealers (2025–2026).

A note on architectural lighting

Of all the decisions made during a renovation, lighting is among the most consequential — and the most often left as an afterthought. Architectural lighting, specified correctly from the start, is what transforms a well-finished room into one that feels genuinely considered. It defines mood, draws attention to texture and detail, and makes a home feel alive after dark. Poor lighting — even in the most beautifully decorated room — flattens everything it touches.

We strongly recommend engaging a specialist lighting designer early in the project — before first-fix wiring begins. Repositioning a light fitting after plastering is expensive. Getting it right at the design stage costs nothing extra.

All specialist costs above are indicative budgets from published UK sources as at 2025–2026 and are shown exclusive of VAT (published dealer pricing may vary in its VAT treatment — confirm when quoting). They do not form part of the room cost estimates in this guide. Lutron system costs sourced from Clearly Automated (clearlyautomated.co.uk), a Lutron Diamond Dealer. Always obtain individual quotes from certified installers.

Professional Fees

Expressed as a percentage of total construction cost. These are indicative ranges — fees vary by project scope, location, and individual consultant. Always obtain written proposals.

* Fees are expressed as a percentage of construction cost and are shown exclusive of VAT — professional fees are themselves subject to VAT at the prevailing rate. Planning application fees, building regulations charges and specialist consultant fees vary by local authority and project type.