Semi-Detached House Extensions

Adding an extension to a property can greatly enhance the living space, adding plenty of character and long-term value. Many homeowners in the UK may feel limited with their options if they live in a semi-detached property, as it can seem complicated with plenty to consider, including planning permission, budgeting and neighbours.

In this guide, BASE discusses some of the most popular semi detached house extension designs that have stood the test of time, transforming living areas with unique and tasteful ideas.

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Side return extension

For a practical extension design that utilises space well, consider adding a side return extension. Originally designed for terraced houses, side return extensions differ from other types of extension as they extend the side of the house rather than the front or the back. Single storey side extensions are a great way to add more floor space without drastically having to change the overall look of the property, resulting in minimum disruption but with far-reaching benefits for your home.

By subtly adding floor space to the side of your home, you can extend your kitchen, or create a dedicated utility area, bringing new dimensions to your living space. Consider a side glass extension to truly maximise light, or a downstairs bathroom for maximum return of investment and added property value.

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Single storey rear extension

Extending the rear of your property to a single storey can add significant space and scope to your home without encroaching too much on neighbouring properties. Rear extensions can also transform the interior of your property significantly by adding space and scope for a dynamic living area. There are plenty of rear extension ideas for a semi-detached property, such as:

Kitchen extension

If your kitchen is located at the rear of the property, a kitchen extension is an ideal solution that adds space and character, without infringing onto neighbouring properties. Kitchen extensions can be perfect for growing families, and also add significant value to the house.

Flat roof extension

Flat roof extensions are a popular choice for homeowners thanks to their simplicity and easy installation. Crucially, most roof extensions are usually covered by permitted development rights, which allows you to build up to three metres without planning permission in most of the UK. One popular flat roof extension design is to add a glass lantern, bathing the space in light and effortlessly creating a focal point for the home.

Glass roof extension

Take flat roof designs one step further with a glass roof extension. This single storey extension incorporates a glazed roof, truly letting the outdoors in. With a modern design and minimalistic aesthetic, natural sunlight will pour through in abundance with a glass roof extension, offering views of the garden and beyond while also adding space.

Single storey sloping extension

A single storey pitched roof extension is another perfect solution for a semi-detached house, with a complementary look and feel that’s in keeping with the original house design. Pitched roof extensions have plenty of other benefits, including increased energy efficiency and durability, thanks to their sloped design. Interior factors also make this a popular choice, as it brings high ceilings into your design for additional scope and character.

Feeling inspired? You can read the latest tips and advice for building a house extension in our blog by clicking here.

Loft conversion

It is possible to convert a semi detached house with a loft conversion, but there are different rules for this. You will need to ensure the house has sufficient structural integrity for the build to go ahead, and due to the nature of the build, you will need to apply for planning permission. You will also need to obtain a document called a Party Wall Agreement, which informs the neighbour of your plans and ensures you have their agreement and permission to convert the loft and shared wall.

Porch extension

Porch extensions are an innovative extension idea that can effortlessly add versatility to a space with minimal intrusion and complication. Many property owners will add a porch extension that incorporates a downstairs WC and cloakroom, all of which add value. With plenty of curb appeal and extra storage, porch extensions don’t infringe on your garden, or neighbouring properties, and can have an ROI of up to 85%.

At BASE, we have years of experience creating unique solutions for homeowners around the UK. You can explore more about our house extension architectural services here.

How much does a semi detached house extension cost?

The average cost of a semi detached house extension is anything from £1250 to £3250 per metre squared, for a typical rear extension.

There are plenty of other costs to consider if you’re building a house extension, including:

Landscaping
Permits
Structural adjustments
Materials and labour
Planning permission costs
Architectural design fees

45 degree rule for extensions

The 45-degree rule is a guideline for homeowners to follow that ensures your build will not infringe on neighbouring properties’ access to sunlight. The guideline will be followed when your plans are submitted to ensure that the proposed extension will not block sunlight. The exact regulations around the 45-degree rule vary between councils, so check with your local area to determine the regulations where you live. It’s worth noting that if a proposed extension violates the 45-degree rule, the council is likely to reject the planning application.

If you’re ready to start your journey and transform your home, get in touch and speak to our experienced team. We’ll help you bring your vision to life, with a bespoke design and unique approach that’s tailored to you.