House extensions: everything you need to know.


This article covers various aspects related to house extensions, including:

  1. Home extension types

  2. Home extension costs

  3. Financing options for a house extension

  4. Inspiring house extension ideas

  5. Common interior design mistakes to avoid in your extension

  6. Environmentally friendly approaches to house extensions

  7. The process involved in house extensions

  8. Regulations governing house extensions

Read on to gain valuable insights into planning and executing a successful house extension project.

Why move when you can improve? With a home extension, you can stay in the area you love while getting the additional space you need. Designed by a skilled architect, a well-executed home extension not only enhances your daily living experience but also has the potential to increase your property value.

In this comprehensive guide, we will help you explore various aspects of home extensions. From planning and building regulations to budgeting and financing, we leave no stone unturned. If you need personalised advice, simply book a FREE consultation.

Types of Home Extensions:

  • Ground floor extension vs first floor extension: Choose between expanding social areas or creating additional rooms with privacy.

  • Front house extension: Enlarge your living room, add a ground floor bedroom, or create a new porch.

  • Side of house extension: Utilise space beside your house to create a compact addition, such as an open-plan kitchen diner.

  • Semi-detached house extension: Extend your property without compromising privacy or triggering party wall matters.

  • Terraced house extension: Overcome design challenges by considering privacy and neighbor rights.

  • Rear house extension: Popular option for expanding key living areas, providing versatility and better connection to the garden.

Costs of Home Extensions:

Before embarking on a project, it is crucial to establish a budget and devise a financing strategy. We are available to assist you in exploring various lending options.

The cost of a house extension can vary significantly based on factors such as:

  • Type of extension

  • Size of the extension

  • Complexity of the design

  • Location

  • Quality of materials and professionals involved

  • Pre-existing site conditions

Can you save money utilising your DIY skills on an Extension?

While taking a DIY approach to a home extension can potentially save you money, it's important to consider the associated risks. Mistakes, particularly in structural elements, can lead to costly repairs that outweigh any initial savings.

Unless you have the necessary qualifications and expertise, we strongly advise against DIY involvement in the following areas:

  • Roofing

  • Plumbing

  • Electrics

  • Demolition

7 tips to keep costs down:

We have a wealth of strategies to help you control costs effectively. When aiming to stay within your budget, consider the following advice:

  1. Simplify pricing by obtaining a comprehensive measured survey and building regulations package.

  2. Carefully evaluate contractor quotes to ensure accuracy and competitiveness.

  3. Thoroughly vet suppliers and specialists to find the best value for money.

  4. Consider hiring a project manager to streamline operations and maintain cost efficiency.

  5. Conduct thorough research on materials to find cost-effective options without compromising quality.

  6. Explore the possibility of temporarily moving out during construction to minimise disruption and potential additional expenses.

  7. Develop a well-structured funding plan that suits your financial situation and aligns with your project's timeline.

Financing your extension:

When it comes to financing your house extension, it's crucial to explore various options beyond relying solely on your savings. Consider these alternatives to ensure you have a well-rounded approach:

  1. House extension loan: For smaller projects, an unsecured personal loan can be a viable option. These loans often have no set-up fees, but be mindful of the higher interest rates. It's advisable to repay this type of loan quickly and borrow less than £30,000.

  2. House extension remortgage: For larger projects exceeding £30,000, you may want to consider remortgaging or securing a further advance. This option leverages the existing and future equity of your home, offering greater flexibility compared to using savings alone.

  3. Personal savings: Utilising personal savings has clear benefits, as it eliminates concerns about interest rates and payment plans. However, keep in mind that it may take time to accumulate sufficient savings, and inflation can impact project affordability over time. Savings are also relatively inflexible, which can be challenging if you haven't budgeted for a contingency fund.

Explore these financing options carefully to determine the best fit for your specific circumstances and project requirements.

Interior Design:

When focusing on architectural plans and obtaining planning permission, it's essential to also consider the interior design of your extension. Thinking ahead about the desired ambiance and functionality will prevent costly mistakes and help you create the space you've always envisioned.

Having worked closely with interior designers, here are some common design mistakes to avoid:

  1. Neglecting the final layout: Plan the room layout in advance, ensuring key furniture items have appropriate placements. Avoid surprises like having a radiator obstructing your desired sofa position or a sideboard without a nearby plug socket for a table lamp.

  2. Failing to integrate the new and original parts of the house: Create a cohesive transition between the new extension and the existing house. Consider using consistent flooring or coordinating wall colors to achieve a harmonious blend.

  3. Underestimating natural light: Maximize natural light in your new space by strategically planning the placement of windows and considering the room's usage throughout the day. For example, prioritise abundant light in an open-plan kitchen and dining area used during daytime, while allowing for a cozy atmosphere in the evening in a living room located in less naturally lit areas.

By addressing these interior design considerations early on, you can avoid regrets and ensure a cohesive and well-lit space that perfectly suits your needs.

Focusing on the environment:


With increasing awareness about environmental impact, homeowners are prioritising eco-consciousness, particularly within their households. Given that homes account for 27% of the UK's carbon emissions, implementing sustainable practices in your home extension plans is a significant step forward. Fortunately, there are several ways to make your extension more environmentally friendly.

Building an energy-efficient house extension involves focusing on three key areas:

  1. Lighting: Opt for energy-efficient lighting solutions, such as LED bulbs, to minimise electricity consumption and reduce carbon footprint.

  2. Heating: Consider sustainable heating systems, like heat pumps or solar thermal panels, to reduce reliance on fossil fuels and promote renewable energy usage.

  3. Insulation: Prioritise high-quality insulation materials and techniques to enhance energy efficiency and minimize heat loss, ensuring a comfortable living environment while reducing energy consumption.

By emphasising these aspects in your house extension, you can contribute to a greener and more sustainable future for your home.

The process:

While each house extension is unique, many homeowners will go through a similar set of tasks. In the past, this process could be fragmented and confusing, but with services like Sime Design, we streamline the journey for you, guiding you seamlessly from Point A to Point B.

Experience the convenience of our all-in-one service with a free quote.

Most projects will progress through the following stages before reaching the construction phase:

  1. Measured survey

  2. Proposed design

  3. Planning permission

  4. Involvement of a structural engineer

  5. Building regulations package

  6. Tendering the project

  7. Contractor selection

You can trust our team to assist you at each step, making the entire process smoother and more enjoyable.

Regulations:

When it comes to regulations, brace yourself for a comprehensive process. From planning permission to building regulations, structural drawings to party wall considerations, there are various hoops to navigate before you can legally commence construction.

The key regulations to focus on include:

  1. Planning permission: Ensure compliance with local planning regulations for your proposed extension.

  2. Building regulations: Adhere to the required standards for structural integrity, safety, energy efficiency, and other aspects of your extension.

Surveying your property is an essential initial step in any project, often underestimated in its importance. Opting for a high-quality survey can significantly impact the accuracy of your project and its budget. Various survey options are available, including commercial-grade laser surveys, measured surveys, hand-drawn surveys, and topographic surveys.

It is possible to build a home extension without planning permission by utilising permitted development rights. However, this still requires obtaining a lawful development certificate to confirm the legality of the project. Certain design guidelines and restrictions apply, and prior approval is required for large rear extensions.

Adding an extension to a listed building is possible but comes with limitations. Full planning permission and listed building consent are necessary. Considerations include the building's history, preservation of character features, protective measures for key elements, size, and design of the extension.