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Whole House Renovation: Plan It From Brief to Handover

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November 12, 2026•6 min read

A whole house renovation goes well when one coherent plan covers the budget, the order of work, the permissions and the design of every room before anything is stripped out. It goes badly when each trade is booked separately and decisions are made as problems appear. This guide sets out that plan for homeowners in England, including how to design a kitchen extension. It also explains why a single team that designs, supplies and installs the work, as we do at Smith Interiors, takes most of the coordination off your shoulders.

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TL;DR

  • Budget for the whole project, not the builder’s headline price: fees, VAT, waste, temporary living and a 10-20% contingency.
  • Work from the outside in and the structure out: repairs and weatherproofing, then services, then layout, then kitchens and bathrooms, then finishes.
  • Planning permission and Building Regulations are separate approvals. Check both before you commit to a design.
  • For a kitchen extension, decide sockets, lighting, plumbing and appliance positions before you choose finishes.
  • One team responsible for design, supply and installation means fewer handovers and fewer gaps between trades.

Table of Contents

What a whole house renovation really involves

A whole house renovation is not one big job. It is a chain of dependent jobs: structural work, roof and windows, plumbing, heating and electrics, insulation, layout changes, kitchens and bathrooms, then plastering, flooring and decorating. Each link depends on the one before it. If the wiring is chased into a wall that is later moved, you pay twice.

That is why the planning stage matters more than any single material choice. The Federation of Master Builders (FMB), the UK trade body for builders, advises that you agree the scope before work begins, get drawings or structural advice where needed, and check permissions and regulations early.

A useful first step is a written brief. Include:

  • What is wrong with the house today: cold rooms, a cramped kitchen, a dated bathroom, poor storage, a dark hallway.
  • How your household lives: who cooks, who works from home, where the laundry and coats end up, how often you entertain.
  • Which rooms matter most and which can wait.
  • The look you want, from modern to traditional.

The brief is what lets a designer turn a pile of ideas into a drawn, costed scheme. Our design process starts there, with how you live, rather than with a catalogue.

Build a whole-project budget

The most common budgeting mistake is treating the builder’s quote as the budget. The FMB lists what a realistic budget includes: the builder’s quote, VAT where applicable, architect or designer fees, structural-engineer fees, planning or building-control costs, skips and waste, temporary living arrangements, and decorating and finishing. On top of that it recommends a 10-20% contingency.

Here is what that means in practice, using round numbers purely to show the arithmetic. Say the agreed works and fittings come to £100,000. A 10% contingency adds £10,000 and a 20% contingency adds £20,000, so you would want £110,000 to £120,000 available before fees, VAT where it applies, skips and any rented accommodation. The contingency is not a treat fund. It is there for what the house reveals once opened up.

Older properties deserve extra caution. The same FMB guidance warns that hidden damp, rot and outdated wiring can emerge as work proceeds. Homebuilding magazine makes a similar point: surveys cannot reveal every concealed problem, so allow flexibility in both money and programme.

Build a whole-project budget

Decide where the money goes first

A whole house budget has fixed and flexible parts. Structure, weatherproofing, wiring and plumbing are fixed: they protect everything else. Surfaces, lighting, handles, soft furnishings and decor are flexible, and they are what makes the house feel finished. Fix the first group, then allocate the second room by room. Kitchens and bathrooms usually carry the largest share of the fit-out because they combine cabinetry, appliances, plumbing, tiling and electrics in the smallest areas.

We publish no fixed prices, because every scheme is bespoke. A design consultation is where your brief becomes a costed proposal. You can contact us to start that conversation.

The order of work

The FMB’s practical sequence runs like this:

  1. Structural repairs and stabilization.
  2. Roof, windows and weatherproofing.
  3. Plumbing, heating and electrics.
  4. Insulation and ventilation.
  5. Layout changes and wall removals.
  6. Kitchens and bathrooms.
  7. Plastering, flooring and decorating.

The FMB checklist sets out this order, and Homebuilding agrees on its core: make the house watertight before internal work, and sequence external repairs ahead of first-fix services and finishes.

The National Self Build & Renovation Centre groups the same journey into four broad stages: assessment and design, strip-out and building work, first fix, and final finishes. It stresses that the exact order depends on the age, condition and scope of the property.

Two practical consequences follow.

Design everything before you build anything. First-fix positions for pipes, cables, lighting and extraction depend on where the furniture, cabinetry and sanitaryware will sit. If the kitchen, bathroom and storage are designed at the start, the electrician and plumber work from drawings rather than guesses.

Order long-lead items early. Bespoke cabinetry, solid wood kitchens and made-to-measure joinery take time to produce. They must be ready when the room is, not ordered after the plaster dries.

How long does it take?

The honest answer is that it depends on scope. The FMB says a like-for-like basic kitchen fit may take a few weeks, whereas a kitchen that forms part of an extension or larger renovation may take several weeks or months, excluding planning time. A full house multiplies that across every room, so a programme drawn up from the finished design is more reliable than any rule of thumb.

Permissions: planning and Building Regulations

These are two separate systems, and having one does not mean you have the other. Epping Forest District Council explains that planning permission and Building Regulations approval are separate. Planning departments are not normally concerned with internal works unless the property is listed, while Building Regulations may apply to anything beyond minor cosmetic work.

Some examples from the same council guidance:

  • A kitchen refit usually needs neither, unless listed-building, structural, drainage or electrical issues apply.
  • Creating a kitchen where none existed is likely to need Building Regulations approval, covering ventilation, drainage, structural stability, electrical and fire safety.

Extensions and permitted development

Many house extensions can go ahead under permitted development, which means national rules grant permission without a full planning application. These rules change. England’s 2024 amendment order came into force on 21 May 2024 and altered several permitted-development classes, with transitional provisions running until 20 May 2025 for some affected rights. Always check the rules in force on the day you apply.

Three checks save the most trouble:

  • Houses versus flats. A London borough’s extensions guidance explains that houses and bungalows may be able to use permitted development, while flats and maisonettes normally need permission for most external changes. The same document confirms that all building work must comply with current Building Regulations whether or not planning permission is needed.
  • Article 4 Directions. Councils can use these to remove permitted-development rights in defined areas. Telford & Wrekin Council, for instance, publishes an Article 4 Direction under which specified extensions and alterations need planning permission despite normally available rights. Ask your local planning authority whether one covers your street.
  • Listed buildings and conservation areas. Internal works can need consent if the property is listed. Check before designing, not after.

For the approvals themselves, your local planning authority and building control body are the authorities. Their role is part of the process, and we take your design through to the drawings those applications need, so they are never an afterthought.

Designing a kitchen extension that works

A kitchen extension is the single most common big move in a whole house renovation, and it is where design decisions have the most leverage. Experts keep returning to one idea: successful extensions are about continuity, not just square meters. Homebuilding’s guidance on open-plan extensions recommends defined zones, layered lighting, varied materials and coherent proportions, with features such as a pantry or back kitchen to keep a large open-plan space calm.

Open-plan kitchen extension with distinct living zones

Layout: think in zones

Grand Designs Magazine advises planning distinct cooking, eating, cleaning and living zones, arranged for natural movement. It suggests placing seating or a breakfast bar near doors or windows so the social area connects to the garden.

A workable layout usually answers these questions:

  • Where does a person stand to cook, and what is within one step?
  • Can two people use the kitchen at once without colliding?
  • Where do the bins, recycling and laundry go?
  • Where do children do homework while someone cooks?
  • Is there a utility room or boot room nearby to keep clutter out of sight?

That last question is where a whole house plan pays off. A kitchen, utility space and boot room designed together, with matching cabinetry, read as one scheme. We design kitchens alongside laundry and boot rooms, understairs storage and bars, so the storage logic runs through the house.

Light and storage

Full-height glazing brings light but takes wall space. Grand Designs Magazine suggests rooflights or a roof lantern towards the rear of the extension to help bring daylight into the darker original rooms. It also recommends tall cupboards, an island, a larder and an adjacent utility room to make up for the lost storage.

Zoning without walls

Livingetc, citing UK designers, reports a move toward “broken-plan” layouts: subtle zoning through joinery and lighting, spaces that can open or close as needed, and transitional features such as covered terraces, deep thresholds or built-in seating rather than relying only on large bifold doors. Bespoke joinery is the natural tool here: a shelving run, a banquette or a media wall can divide a room while keeping sightlines open.

The garden connection

Ideal Home describes a south London Victorian house where the floor level was lowered and a flush threshold with concealed drainage, matching limestone inside and out, and fixed and sliding glazing created a strong link to the garden. You do not need to copy it, but the principle holds: carry the same materials and tones across the threshold.

Settle the technical decisions first

Sockets, lighting, drainage, extractor position, appliance locations and window placement all need deciding before finishes, because they are costly to change once the room is built. This is the point at which designing and supplying the kitchen as one package helps most: cabinetry dimensions, appliance specifications and service positions are fixed together on one set of drawings rather than reconciled between suppliers.

Living through the work

A whole house project is disruptive, and planning for that is part of the job. The National Self Build & Renovation Centre recommends securing and surveying the property, obtaining approvals, making it weather-tight, safely isolating services, and arranging access, storage, welfare facilities and waste management before the main work starts.

That translates into a few household decisions:

  • Phase or vacate. Decide whether you will move out for the heaviest stages or keep one kitchen-substitute and one working bathroom. Temporary living costs belong in the budget.
  • Protect what stays. Agree what is being kept, stored or covered before work begins.
  • Fix the decision dates. Most delays come from late choices on tiles, handles, lighting and flooring. A schedule of selections, each with a date, keeps the programme moving.
  • Keep one point of contact. Many people who commission a renovation are busy professionals. A single person coordinating the trades saves hours of calls.

Why one team for the whole house

When design, supply and installation sit with different parties, gaps open: the designer draws something the joiner cannot build, the tiles arrive after the plumber has left, nobody owns the snagging list. Our model is built to close those gaps. We are a family-run business offering bespoke design, supply and installation, with full home project management, so the same team that designed your rooms sees them built.

It also keeps the whole house consistent. Kitchen, bathrooms, bedrooms, home office, flooring, doors and windows, lighting, wall finishes, soft furnishings and decor can be specified together, so a traditional in-frame kitchen and a modern bathroom still feel like one home. You can see how this works in practice in our real homes projects and the bathroom transformation.

How we can help

If you are planning to renovate several rooms or the whole house, our interior design packages, The Concept, The Signature Room and The Residence, are the place to start. They cover design, and we then supply and install the scheme, from kitchens and bathrooms to the finishing touches. Our approach is bespoke and transparent, with the design shaped around your lifestyle.

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See the interior design packages to find the scope that fits your home, or get in touch to talk through your plans.

FAQ

Is it better to renovate the whole house at once or room by room?

Doing it at once lets you plan services, storage and finishes as one scheme, and avoids opening the same walls twice. It is more disruptive, so it suits households that can plan for temporary living. Room by room spreads cost and disruption, but works best when every room is designed up front, so later phases match the first.

How much contingency should I add?

The FMB recommends 10-20% on top of the project budget. Choose the higher end for older houses, where damp, rot or outdated wiring can appear once surfaces are opened.

Do I need planning permission for a kitchen extension?

Not always. Many houses can use permitted development, but flats and maisonettes normally need permission, and an Article 4 Direction or a listed building can change the picture. Building Regulations apply separately. Check with your local planning authority, using the rules in force on the date you apply.

In what order should the work be done?

Structure and weatherproofing first, then plumbing, heating and electrics, insulation, layout changes, kitchens and bathrooms, and finally plastering, flooring and decorating. The exact order depends on the age, condition and scope of your property.

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