House Extensions in Perth

A well-planned extension can transform how you live without the cost and upheaval of moving. We deliver single-storey, two-storey, and wrap-around extensions tailored to your property and lifestyle.

From foundation to finish, every extension is managed under one contract with transparent pricing and realistic timelines.

Marshall & Co has built extensions on every type of property across Perth and Perthshire — from Victorian terraces and 1930s bungalows to modern detached homes. We understand Scottish building regulations, local planning requirements, and the practical challenges of building in the Scottish climate.

Why Marshall & Co?

Single-storey rear extensions are the most popular type of house extension in Perth and Perthshire. They typically extend from the back of the property to create a larger kitchen, kitchen-diner, or open-plan living space. Many of our clients choose to install bi-fold or sliding doors to connect the new space with the garden, flooding the room with natural light and creating a seamless indoor-outdoor flow.

Two-storey extensions provide additional space on both levels — perhaps a larger kitchen downstairs with a new bedroom and en-suite above. They offer excellent value per square metre compared to single-storey extensions because they share the same foundations and roof structure across two floors.

Side-return and wrap-around extensions make use of narrow passages alongside the house or combine rear and side extensions into one L-shaped or U-shaped addition. These are particularly effective on Victorian and Edwardian properties where side returns are common.

We also build porch extensions, sunrooms, and orangeries for clients who want to add space and character without a full structural extension. These projects are often quicker to complete and may not require planning permission.

In Scotland, building regulations are administered through the building warrant system rather than building control as in England and Wales. Every structural extension requires a building warrant before work can begin. This involves submitting detailed plans, structural calculations, and specifications to the local authority for approval.

Many single-storey rear extensions also fall under permitted development, meaning they don't require separate planning permission — only the building warrant. However, this depends on the size of the extension relative to the original house, the distance from boundaries, and other factors. We assess your specific situation during our initial site visit and advise you clearly on what approvals are needed.

For extensions that do require planning permission, we work with experienced architects who understand Perth & Kinross Council's requirements and can design proposals with the best chance of approval. We handle the full application process so you don't need to navigate the paperwork yourself.

House extension costs in Perth and Perthshire typically range from £1,200 to £2,200 per square metre for a standard specification, including foundations, structure, roofing, and basic interior fit-out. A typical single-storey rear extension of 20–30 square metres would therefore cost between £24,000 and £66,000 depending on specification.

Factors that influence cost include the type of foundations required (which depends on ground conditions), the roofing style (flat roofs are generally less expensive than pitched), the level of glazing (bi-fold doors and roof lanterns add cost but also add significant value), and the interior specification (a basic plastered room versus a fully fitted kitchen-diner).

We provide detailed, fixed-price quotations with every element itemised. This means you can see exactly what each component costs and make informed decisions about where to invest. There are no hidden extras, provisional sums, or day-rate surprises.

Understanding the build process helps you plan around the disruption and anticipate key milestones. A typical single-storey extension follows this sequence: groundwork and foundations (week 1–2), blockwork walls to roof level (week 3–5), roof construction and weatherproofing (week 5–7), windows and external doors (week 7–8), first-fix electrics and plumbing (week 8–9), plastering (week 9–10), second-fix, kitchen fitting, tiling, and flooring (week 10–13), and final decoration and snagging (week 13–14).

Throughout this process, your project manager provides weekly updates including photographs, progress against programme, and any decisions required. We pride ourselves on realistic timelines — we don't promise eight weeks and deliver in sixteen. Our programmes are based on real experience of how long each stage takes in practice, factoring in Scottish weather conditions and material lead times.

We also take great care to minimise disruption to your daily life during the build. Existing rooms are sealed off with dust barriers, site areas are kept tidy, and we agree working hours in advance. Most of our clients continue living in their homes throughout the extension build.

Building an extension is one of the biggest investments you'll make in your home, so choosing the right contractor is critical. Marshall & Co brings over fifteen years of extension-building experience across Perth and Perthshire, with a portfolio of completed projects you can view in our gallery or visit in person.

We are fully insured with both public liability and employer's liability cover. All electrical work is carried out by NICEIC-registered electricians, and all gas work by Gas Safe-registered engineers. We hold all necessary certifications and comply fully with Scottish building regulations.

Our clients consistently rate us five stars for communication, workmanship, and project management. We're happy to provide references from recent extension projects so you can speak directly with homeowners who've been through the process with us.

Single contract covering every trade from groundwork to interior fit-out

Architectural design support with trusted local architects

Building warrant applications handled and managed to approval

Fixed-price quotations with no hidden extras or provisional sums

Realistic, weather-adjusted build programmes you can rely on

Weekly progress updates with photos and clear communication

NICEIC and Gas Safe certified tradespeople on every project

Fully insured with public liability and employer's liability cover