Before you embark on extending your home, there are a few things every homeowner should sit down and consider. After all, even modest additions are big projects to undertake and the last thing you want to encounter is surprises. 

We asked the experts over at Resi, to share their knowledge on the best way to go about extensions as well as the pitfalls you need to avoid. After all their all-in-one platform helps homeowners through every stage of the extension process. From architectural design to planning, building regulations to getting onsite, our in-house team of experts have helped over 4000 people in the UK navigate (what can feel like) a daunting process. 

If you’re wondering where to start with your project, here’s their breakdown of everything a homeowner needs to consider before extending their home…

Will it add value to your home?

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Image Credit: My Bespoke Room

Even if you’re not planning to sell your home anytime soon, it’s important to understand what your project may or may not do for the value of your home. Extending is an expensive project but can, in many cases, reward your investment when it comes to putting your home back on the market. 

How much value you add will depend on…

  • The quality of the work
  • What (if any) additional rooms you’ve created
  • Local ceiling prices 

On this last point, you will find that some areas suffer from low ceiling prices, which means there’s a limit to how much value you can add.

To work out if your home is affected by a ceiling price, research the prices in your area and see what patterns emerge. 


Have you got enough budget?

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Image Credit: My Bespoke Room

You’ve put money aside, but have you got enough for everything required? While many people plan for the contractor fees and materials, there are a lot of hidden costs that some aren’t prepared for. Such as…

  • Legal fees
  • Stamp duty and land tax
  • Measured surveys
  • Architecture fees
  • Structural engineer fees
  • Planning application fees
  • Building regulation fees
  • Warranty
  • Services
  • Waste removal
  • External works

However, don’t let this put you off. Architects can often advise on pricing and there are brokers who specialise in home development loans, should you want to utilise the equity in your property, rather than rely on savings. 


Do you understand the timings?

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Image Credit: My Bespoke Room

Extending your home isn’t a quick job. In fact, you might be surprised by how long the whole process can take. For instance, planning permission takes 8-10 weeks to obtain, while trying to reach a party wall agreement with a neighbour can stretch on for 2 or 3 months! 

On average, we estimate the average home extension takes between 7 and 15 months to complete. 

Do you have permitted development rights?


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Permitted development rights allow you to extend your home without needing a full planning application. However, there are a number of guidelines your project will need to follow and not every home is going to qualify. If you live in a flat, maisonette, listed building or conservation area, your rights are either going to be limited or not applicable. What you can build will also depend on where you live in the UK. 

For those homes who do qualify, you may be able to create a…

  • Rear extension
  • Side extension
  • Two-storey extension
  • Garage conversion
  • Loft conversion
  • Annexe
  • New additional storey

The most notable exception is a wraparound extension. The structural work and space these projects take up make them an unlikely candidate for the scheme. 

It’s also worth noting that even though a full application won’t be required, you should still go through the planning process, either by applying for prior approval or a lawful development certificate.

Permitted development isn’t necessarily a quicker route but it is less subjective. If you’re looking to complete a straightforward extension, using this planning route means you won’t be at the mercy of a strict local authority.

Don’t forget building regulations


Image Credit: My Bespoke Room

While many people understand the need for planning permission, building regulations can often get forgotten. These regulations set out all the safety standards your property must comply with. If you fail to meet these, you could face penalty fines or even be asked to demolish your build.

Building regulations are extensive and cover…

  • Structure
  • Fire Safety
  • Site preparation and resistance to contaminants and moisture
  • Toxic substances
  • Sound
  • Ventilation
  • Hygiene
  • Drainage and waste disposal
  • Combustion appliances and fuel storage systems
  • Protection from falling, collision and impact
  • Conservation of power and fuel
  • Access to and use of buildings
  • Electrical safety in dwellings

To ensure these guidelines are met, we highly recommend commissioning a building regulations package. This can be put together by your architect or a structural engineer (more on these guys below). They will correlate the work of several building regulations specialists into one set of highly detailed drawings, which your contractor can then use during construction to make sure no mistakes are made.


Building a new home or extension? We can use your architect's plans and help you create a cohesive, functional and beautiful space. Our consultancy service is £195 for four hours then £65 per additional hour. Book a free call with us now so we can set this up for you! 



You will need a structural engineer

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Image Credit: My Bespoke Room

Regardless of whether you commission a full building regulations package, all extensions require input from a structural engineer. It’s their job to provide key calculations that will keep your project standing up. 

These technical specialists will assess your project and provide guidance on…

  • Materials you plan to use
  • The site location
  • Weight of the build
  • Structural support needed


Where will you live during construction?

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Image Credit: My Bespoke Room

It’s a factor often overlooked by homeowners, but will your home be habitable during the construction of your extension? Depending on the work, your water may have to be shut off; you’ll have builders moving material and waste through your home; you may even lose vital spaces, such as your bathroom or kitchen.

When it comes to facing these issues, you have a few options. If the work is happening at the rear, and your garden allows your contractors to avoid going through the rest of your home, you could stay put. Alternatively, you might opt to rent another home with a short-term contract. Moving will be a pain, but will let you have a normal home life for the length of the build. Caravans are another option if you have space nearby. However, families with kids might not relish the idea of such close quarters.


Get an architect onboard

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Image Credit: My Bespoke Room

Why choose an architect? Ultimately, if you’re extending your home, you want to make sure you’re getting the best build possible. That means utilising the most space, getting the best layout, and avoiding as many admin headaches as you can. An experienced architect can not only ensure you’re unlocking the maximum amount of potential from your property, but they can also act as your planning agent and liaise with other experts during the building regulations process. 

Unsure? Not to worry, many architects offer free consultations. These early conversations are not only a great way to learn more about working with an architect, but they can also help provide insight into other areas of your project, such as planning and budgets. 

Book a free consultation with Resi here.

Once you have done this My Bespoke Room can help bridge the gap between your architect's plans and create a cohesive, functional and beautiful space. Our consultancy service is £195 for four hours then £65 per additional hour. Book a free call with us now so we can set this up for you! 



You’ll need to take out insurance

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Image Credit: My Bespoke Room

Did you know, during construction, you won’t be adequately covered by your regular home insurance, especially if you are not going to be in the property during the build?

There are some great policies out there and most standard home insurers will sometimes look to cover small amounts of work, but will normally limit cover to “FLEE” only (Fire, Lightning, Explosion and Earthquake). This leaves a rather large gap in your protection.

To make sure your home is safe, we recommend you review your current policy and talk to your provider to work out your options. 


Are you on good terms with your neighbours?

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Image Credit: My Bespoke Room

Your neighbours could play a big part in your project’s success if you share what is known as a ‘party wall’.

A party wall is a wall, boundary, or outbuilding that you share with another household. These are common between terraced and semi-detached houses, but can also affect detached properties if you share a garden wall or invisible boundary line. If your project affects a party wall or you plan on excavating within 3 to 6 metres (depending on the depth of the new foundations) of your neighbour’s property, then you need to obtain permission from the affected households at least 2 months before any construction occurs.

The first step of this process is to send out a party wall notice, which can be prepared either by yourself or a party wall surveyor. If your neighbour gives written consent, then you’re in the clear. However, if they dissent or don’t reply, a party wall award will need to be put together and this process can take months, depending on how against the work your neighbour is. On top of this, you’ll be the one covering the costs for both yourself and next door.

Want to avoid the headache? Don’t be afraid to go round with a bottle of wine before your project begins! 

Looking to extend your home? Try Resi’s Quick Quote calculator to discover the cost of getting our experts by your side. 

Or maybe you have an extension on the way and would you like some help designing your new space? Our professional designers will help you invest in your home transformation and can help you make the most of every nook and cranny!  Get started today by completing this quick and easy 15-minute brief:



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