House extension ideas and advice for semi-detached houses

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If you live in a semi-detached home, you might be wondering what your options are when it comes to house extension ideas and home improvements. Semi-detached homes usually have space on one side with a neighbour attached on the other side. This means more things to consider for semi detached house extension ideas. Here are our top five things you should know when planning a house extension.

Do you need a semi-detached extension for your Hertfordshire home?

First, ensure you use your current space as much as you can. Many people who consider extending don’t realise that they have unused space in their home already. Look at your existing floor plan. Would making your ground floor open plan help boost your available space? Decide what you need your extension for; is it a guest bedroom or an extra dining room perfect for entertaining? The use of your new space will help you plan the house extension ideas and ensure you really need a semi-detached extension for your home.

Be neighbourly with your semi-detached extension ideas

Consideration needs to be given to the neighbours your home is attached to. If you are on friendly terms with them, it’s only polite to let the know what you’re planning for your semi detached extension. Bear in mind any building work could disrupt and disturb them as well as you. During the build you may need access to their garden to bring materials in so best to get their consent early on. Let them air any concerns they have so you can put their mind at rest. This may prevent them slowing down your plans later on.

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Know about the right to light for your home extension

The ‘right to light’ is an easement in planning law. It allows anyone who has received natural light for 20 years or more through a window or similar to block any development that may now prevent this. If your neighbour has a window that could be blocked by your semi-detached home extension idea, they could override your planning permission. This normally only applies to light that contributes to the reasonable use of the building. Blocking a view or small amount of light are planning considerations. In London, where homes are close together and space is at a premium this issue can be more common. Talk to a property lawyer and your designer to find out more.

The Party Wall Act for semi-detached home extensions

This was brought about to prevent disputes between neighbours who share a wall. If your planned extension requires building or digging of foundations within 6m of a boundary then you will need to comply with the Party Wall Act. A surveyor is normally required to set out when work can take place and to survey the condition of your neighbour’s property before and after to protect you from false claims.

Bear in mind that the party wall act generally relates to loft conversions, building a new wall for an extension and most excavation work for extensions and basements. Read our guide to find out if you’ll need a foundation for a conservatory extension. 

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Keep your semi-detached home extensions subtle

If you have a traditional looking semi-detached home, you may be asked to try and maintain the look of your home as much as possible to avoid it contrasting overly with your neighbour.

This could be by using the same materials or a similar colour for house extension ideas for semi detached homes. You can still incorporate modern elements like bifolding doors or how about a skylight? Another issue you might not have thought of is that rooms that were on the outside of your home now become central which can restrict their natural light. This can be solved by adding internal windows or by adopting an open plan design throughout your home. If you’re considering a semi-detached home extension to enhance your home’s energy efficiency, read our guide here.

Other home extension design issue considerations

Bear in mind that if you have your heart set on a fully glazed extension or roof for your semi-detached extension, you may be overlooked by your neighbours as they will be able to see through the glass panels. Therefore, it may not be the best extension idea. A solid conservatory roof will provide you with more privacy. If you still wish to enhance the natural light in your home, a skylight provides the best of both worlds with additional natural light but will still attain your privacy. Read our five tips for buying skylights for your Greater London home!

Another factor to consider is if your semi-detached home extension ideas will overlook your neighbour’s property. Extensions can sometimes be rejected if they will significantly affect the living conditions of your neighbours or invade their privacy. The location of any bedrooms or living rooms in your neighbours home can affect what you can do as can the position of your home in relation to the sun.


Will you need planning permission for your semi-detached extension ideas?

In many cases, a single-storey house extension will be considered permitted development not needing planning permission if certain conditions are met. These include:

  • You must not extend beyond the rear wall of the original house by more than 3 m
  • No more than 50% of the surrounding land/garden is taken up. This could significantly decrease your enjoyment of your garden as well as the value of your home
  • The highest part must not be higher than the original roof
  • If you live in a period property or conservation area, you will have other restrictions

How much will a semi-detached home Lantern roofextension cost?

The total cost of a semi-detached home extension will vary greatly depending on the scope of your project, so it’s important to think about the goals of your home improvements.

If you’re looking to enhance your home on a smaller budget, a set of bifold doors can open and divide your living spaces at a smaller cost than a house extension. If it’s natural light you’re looking for, skylights and sliding doors provide an abundance of natural light without needing to extend your home.

It is important to set a budget for a semi-detached home extension, and we suggest setting aside a little extra for any unexpected situations that may arise along the way. In your budget, you should also consider the expenses for interior furnishings to maximise your additional living space and give it the homely feel. Here’s our guide on how to decorate conservatories on a budget. 

A home extension for your semi-detached house is a great way to add value to your home and increase its kerb appeal. Find out more here on how to add value to your Greater London home.

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The perfect double glazing installer for your Hertfordshire home

Detached house with white sliding doorsIf you’d like to discuss your dream home extension or get any advice on planning laws, get in touch with us today. We can create the perfect space for your family and take care of the legal side so you don’t have to worry about a thing. If a proper extension is too much, why not consider a conservatory, orangery or atlas skyroom? Here’s our guide on the difference between an orangery and a conservatory. These give you a useable space all year round with minimal building work needed.



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