Can You Have a Loft Conversion in a Semi-Detached House?

A loft conversion is one of the most effective ways to maximise space and add value to a property. If you own a semi-detached house, you may be wondering whether a loft conversion is possible and what considerations need to be taken into account. The good news is that, in most cases, a loft conversion in a semi-detached house is entirely feasible. Here’s everything you need to know

Is a Loft Conversion Possible in a Semi-Detached House?

Yes, a loft conversion is possible in most semi-detached houses, provided that your roof space is suitable and the project complies with building regulations and planning requirements. The key factors to consider include:

• Available head height – Ideally, you need a minimum internal head height of 2.2 metres from the floor to the highest point of the roof.
• Roof structure – Older properties with traditional cut roofs are often easier to convert than modern trussed roofs, which may require additional structural work.
• Planning restrictions – While many loft conversions fall under permitted development rights, some properties may require planning permission.

Types of Loft Conversions for Semi-Detached Houses

Several types of loft conversions are suitable for semi-detached homes, including:

• Velux (Rooflight) Conversion – The simplest and most cost-effective option, involving the installation of skylights without altering the roof structure.
• Dormer Loft Conversion – A popular choice that extends the existing roof to create more space and headroom. A rear dormer is often permitted development.
• Hip-to-Gable Loft Conversion – Ideal for semi-detached houses with hipped roofs, this conversion extends the side of the roof to create additional floor space.
• Mansard Loft Conversion – A more extensive conversion that significantly alters the roof structure to maximise space, often requiring planning permission.

Do You Need Planning Permission?

Many loft conversions in semi-detached homes do not require planning permission as they fall under permitted development rights. However, you will need to apply for planning permission if:

• The conversion exceeds 40 cubic metres of additional roof space.
• The alterations extend beyond the existing roofline.
• You live in a conservation area or a listed building.
• The project includes a balcony or veranda.

To confirm whether your project requires planning permission, consult your local planning authority or check the Planning Portal website.

Building Regulations and Party Wall Agreement

Regardless of whether planning permission is required, all loft conversions must comply with building regulations to ensure structural integrity, fire safety, insulation, and accessibility.

If your conversion affects the party wall shared with your neighbour, you must serve a Party Wall Notice under the Party Wall Act 1996. Your neighbour has 14 days to consent or dispute the plans. If they object, a party wall surveyor may be required to resolve the matter.

How Much Does a Loft Conversion Cost in a Semi-Detached House?

The cost of a loft conversion varies depending on the type and complexity of the project:

• Velux (Rooflight) Conversion – £20,000 to £30,000
• Dormer Loft Conversion – £35,000 to £50,000
• Hip-to-Gable Loft Conversion – £40,000 to £55,000
• Mansard Loft Conversion – £45,000 to £60,000+

A loft conversion in a semi-detached house is a great way to add extra space without moving home. With careful planning and expert advice, you can transform your loft into a functional and stylish living area.

Are you considering a loft conversion? Get in touch with one of the Core Loft Conversions experts to explore your options and start your home transformation today!