7 things to know before adding a house extension | homify | homify
Error: Cannot find module './CookieBanner' at eval (webpack:///./app/assets/javascripts/webpack/react-components_lazy_^\.\/.*$_namespace_object?:3646:12) at at process._tickCallback (internal/process/next_tick.js:189:7) at Function.Module.runMain (module.js:696:11) at startup (bootstrap_node.js:204:16) at bootstrap_node.js:625:3

7 things to know before adding a house extension

Johannes van Graan Johannes van Graan
Elverson Road SE13 Lewisham | Kitchen extension by GOAStudio | London residential architecture Modern
Loading admin actions …

A house extension can truly transform not only your home, but also your available space and day-to-day lifestyle. And that’s without having to move to a new property! 

But whether you want to extend up or to the side, there are a few things to keep in mind to ensure your home-extension project commences and concludes with as few hiccups as possible…

1. Check that it complies with Building Regulations

Even if your project can proceed under Permitted Development rights (meaning no Planning Permission is needed), work must still get Building Regulations approval. Under Building Regulations, minimum requirements are set out to ensure structural integrity, fire safety, energy efficiency, damp proofing, ventilation and other key aspects that help to make a structure safe are adhered to. 

Most repair work is excluded from Building Regulations, yet replacing windows, under-pinning and rewiring are the exceptions. But apart from certain new buildings (like sheds, outbuildings and some conservatories), all new building work (which includes alterations) need to comply with Building Regulations. 

2. Know if it’ll add value or not

Elverson Road SE13 Lewisham Architect designed house extension by GOAStudio | London residential architecture Modern Bricks
GOAStudio | London residential architecture

Elverson Road SE13 Lewisham Architect designed house extension

GOAStudio | London residential architecture

The value that your extension will add to your home needs to be greater than the project’s cost. That can be tricky to assess, yet looking at similar local properties and checking their selling prices can be a useful guide.

Keep the ceiling value of your area in mind, and be prepared to adjust your plans if needed. 

3. Go with the right professional(s)

Fulham, London - rear extension, loft conversion and entire house renovation including inserting swimming pool by Zebra Property Group
Zebra Property Group

Fulham, London—rear extension, loft conversion and entire house renovation including inserting swimming pool

Zebra Property Group

Various professionals can be relied upon for your home extension project including Architects, Interior Designers / Decorators, Architectural Technicians, etc. 

It never hurts asking for recommendations from friends, family and neighbours. But be sure to also scope out firms and companies online to see reviews, past projects completed, etc. 

4. What if I’m extending above a single storey?

It may seem tempting to extend above a single-storey extension, but bear in mind that these structures may not always be able to support the load.

But there are circumstances where the old structure isn’t up to scratch, like underpinning existing shallow foundations; strengthening or bypassing the existing with a steel frame bedded in new concrete pad footings; or demolishing and rebuilding entirely from scratch. Usually, the latter makes the most sense in terms of expenditure. 

5. Take note of what type of extension you’re planning

Loft Conversion Bathroom Modern bathroom by Urbanist Architecture Modern
Urbanist Architecture

Loft Conversion Bathroom

Urbanist Architecture

Remember that what you extend will also greatly dictate additional factors to keep in mind. For example, extending a kitchen means you must confirm the position of your units, cooker and white goods before work starts in order for electrics, ventilation and plumbing to be properly planned ahead of time. 

The same goes if you’re planning on building a two-storey extension with a new bathroom or en-suite.

6. Staying put or moving out?

Basement Extension and Refurbishment – Streatham by Armstrong Simmonds Architects Modern
Armstrong Simmonds Architects

Basement Extension and Refurbishment – Streatham

Armstrong Simmonds Architects

It’s not mandatory to move out while that extension project is underway, but sometimes it makes the best sense to get away from all that dust, noise, and mess. And remember that staying put might also mean you’re slowing down the progress while all those builders and other professionals attempt to carry on with their work. 

Be sure to discuss this with your household before the project starts and, if need be, arrange temporary accommodation (short-term rental, hotel, or staying with friends / family) ahead of time.  

7. Connecting old and new

Rear elevation showing timber extension Modern houses by Neil Dusheiko Architects Modern
Neil Dusheiko Architects

Rear elevation showing timber extension

Neil Dusheiko Architects

Your project’s success will definitely be affected by how well that extension sits alongside your existing house. And deciding beforehand if your house extension will complement or contrast with the main house can help to speed the process along. 

homify hint: Should you want to match your house extension to the rest of the property, you need to source matching materials, which is occasionally easier said than done. Remember that one simple mismatch can stand out like a sore thumb!

Have a look at these Home renovations that don’t require planning permission

Additional bathroom? Bigger kitchen? What house extension are you currently planning?
Whitton Drive by GK Architects Ltd Modern

Need help with your home project?
Get in touch!

Discover home inspiration!