House extensions and building designers that you can count on

TENNA is a firm that provides expert house extension designs through an experienced staff of architectural house builders. Designing architecturally & practically relevant additions for you and assisting with council approvals and construction permits. Providing all types of home renovation suggestions to help you improve your home!

  • Affordable & Customised Extensions
  • Expert Planning & Design Process
  • End-To-End Management
  • Leading Home Renovation Design & Construction

Award-winning custom home designs

Organise your free consultation on 1300 283 001

Unique & Fully Customised Extension Architectural Designs

A brand new dream home with all the features you’ve always wanted

An Expertly Designed Home Addition Transforms The Unique Concept You Have For Your Home Into Reality

The building approval team can assist you in obtaining council approval and any necessary construction permits for your planned house extension design. Working with you to develop a cutting-edge house addition that is architecturally unique, meets your precise demands and specifications, whether it's for a:

  • Kitchen Or Bathroom Extension
  • Installing An Entirely New Floor
  • More Room Additions To Expand Your Living Area
  • Expanding The Size Of Your Rooms
  • Home Improvement To Improve Home Functionality

Add value to your home with an architecturally innovative extension design

The Perfect Way To Add Space And Value To Your House

Home extensions & renovations are excellent ways to increase the value of your home! This is because they give you extra living space and make it possible for homeowners to do more things they love. House extensions are a great way to update your existing property by adding new features that enhances the level of livability. Whether it relates to:

  • Designing Unique & Wonderful New Floor Plans
  • Creating A Home That Will Be Excellent For An Bed And Breakfast Rental
  • A Loft Extension

Organise your free consultation for your house extensions

Choose home floor area extensions and modifications that are guaranteed to be finished on time while also being innovative in the fastest time possible.

Choose from a vast range of house extension designs

Affordable & Expert Designs

  • Single Storey Extensions
  • Double Storey Additions
  • Room In Loft Extensions
  • Side Return Extension and more!

Custom design process

This preliminary planning stage includes determining your project's objectives. After determining which council rules must be followed and the drawing of the first drafts of the design has been completed, a concept design for your consideration will be provided.
The creation of the design will commence while incorporating your input. After providing a timetable of planned quality materials, consultation feedback will be provided, followed by approval for the design and drawings and the confirmation of council requirements.
After obtaining DA / CDC approval, you will be required to sign a Housing Industry Association (NSW) Building Contract and pay a Commencement Fee of 5% less than any design fees already paid. Your financial institution's authorisation is required.

Councils we work with:

Are you thinking of adding a home extension?

An Intelligent And Affordable Way To Create Your Ideal Home

Rather than buying a new home, consider building your ideal house yourself. It's a cost-effective and reasonable alternative to purchasing a brand-new property.

House improvements can significantly enhance the value of your home.

You want to stay in your current neighbourhood while increasing the value of your house.

A house extension design provides the opportunity to add features and improved functionality to your existing home.

You have a growing family and are looking for ways to turn your house into the ideal place for a larger family


Can I build an extension on top of my existing house?

Yes, as long as your local council approves the plans. The team at TENNA are uniquely qualified to help you with DA, CDC and Construction Certificate approvals.

What size should my extension be?

The size can vary depending on what you want to do with it and how big your house is. For instance, if you're going to add a family room or kitchen to your home, the extensions would likely be significant. If you only wanted more space for storage, then it would be smaller.

How long does an extension take to build?

It depends on how big and complex the design is and the requirements from council for approvals. No single lot is the same as another. A small essential house addition with a single room extension can take up to four weeks. At the same time, a more extensive project may last several months or even longer.

Is it possible for me to influence the extension's design?

Absolutely! For a streamlined process, you'll work with one designer throughout the entire process, end-to-end. The design team is always ready to listen to your precise requirements, ideas, and aspirations to make your fantasy home a reality

What are your house extensions costs?

This depends on the size and complexity of your house addition and what council approvals are required for construction (building permits, DA/CDC). TENNA strives to deliver a cost-effective approach from start to finish during the design & implementation of your project.

What is the best way to build a sustainable home?

There are many eco-friendly or sustainable design ideas to select from. The building and design team will work with you on any idea you have, large or small.

Choose from a vast range of house extension designs

Custom Living

Completely custom sustainable living

Flexible PROCESS

Flexible design & construction process

Open Communication

Easy to communicate

5-Star Rating

You engage with one designer from beginning to end

your own variation

Make your own variations throughout the construction process


Reliable, personalised & end-to-end customer experience


Affordable design & building solutions

Professional Team

Experienced & expert sustainable house designer & building team

Happy clients

Take a look at the many great reviews our custom home designers & builders have received for their work

Contact us for a free consultation!

Designing, constructing, and finishing professional house extensions on time and on budget, every time. Making sure your ideal house may be built without you leaving!

Don't be afraid to contact the team if you have any questions regarding house extensions you desire.