Frequently Asked Questions About Building Projects in Farnham

If you're planning a home extension, refurbishment, or structural alterations in Farnham, you're likely to have plenty of questions before work begins.

Over the years, we’ve spoken to hundreds of homeowners across Farnham and the surrounding villages who are navigating the early stages of a building project. Many of the same questions come up time and time again.

Below are some of the most common questions we hear from homeowners considering a project.

How much does a home extension cost in Farnham?

The cost of an extension in Farnham varies depending on size, design complexity, ground conditions, and the specification of finishes.

As a rough guide in the current market:

• Single-storey extensions typically range from £2,000 – £3,000+ per m²

• Double-storey extensions may range from £1,800 – £2,500+ per m²

• High-spec kitchens, glazing systems and structural alterations can increase costs further.

Many projects run into difficulty because early cost estimates do not fully account for structural steelwork, drainage alterations, or labour allowances.

Understanding what should be included in a quote before work begins is one of the most important steps in protecting your project budget.

Do I need planning permission for an extension in Farnham?

Not all extensions require full planning permission.

Some projects fall under Permitted Development, which allows certain extensions without submitting a full planning application. However, the rules depend on factors such as:

• The size of the extension

• The type of property

• Whether the property has already been extended

• Whether the property is in a conservation area

Even where planning permission is not required, building regulations approval will still be necessary.

How long does a typical extension take to build?

The timeline for an extension varies depending on scale and complexity.

Typical timeframes are:

• Small single-storey extension: 10–14 weeks

• Large single-storey extension: 14–20 weeks

• Double-storey extension: 16–26 weeks

These timelines can be affected by weather, structural complexity, material lead times, and design changes during construction.

Proper sequencing of trades is essential to keep projects moving efficiently.

Why do some building quotes vary so much?

It is very common for homeowners to receive quotes that differ significantly.

This usually happens because the scope of work included in each quote is not identical.

Common omissions from cheaper quotes include:

• Structural steel installation

• Waste removal and skip costs

• Drainage alterations

• Electrical upgrades

• Decoration

• Contingency allowances

When these items appear later in the project, the overall cost can increase substantially.

This is one of the reasons homeowners should take time to carefully compare quotes before choosing a contractor.

What should I look for when choosing a builder in Farnham?

Choosing the right builder is one of the most important decisions in any project.

It is sensible to look for:

• Experience with similar projects

• Transparent and detailed quotations

• Strong local reputation

• Clear communication throughout the process

• Proper insurance and professional accreditation

A good builder should also be able to explain how the project will be sequenced and managed from start to finish.

What is the biggest mistake homeowners make before building work starts?

One of the most common issues we see is homeowners signing contracts based on incomplete or poorly detailed quotes.

If key structural elements or realistic labour allowances are missing from the initial pricing, the project budget can quickly escalate once work begins.

To help homeowners understand this process better, we created a short guide explaining how to properly review and compare building quotes before committing to a contractor.

The guide is available to download from our website and is designed to help homeowners avoid some of the most common budgeting mistakes.

Thinking About a Building Project in Farnham?

If you're considering a home extension, refurbishment or structural alterations project in Farnham, careful planning at the beginning of the process can make a significant difference to the success of the build.

For advice or to discuss a potential project, feel free to contact Forsyth Construction Surrey Ltd.

You can also read more guidance for homeowners on our website.