info@keystonebuilding.com.au
02 4722 5466
5.0
38+ GOOGLE REVIEWS

Your home addition specialists

With over 20+ years’ experience in Sydney’s north-west, we transform homes to complement our client’s lifestyles and budgets.

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With over 20+ years’ experience in Sydney’s north-west, we transform homes to complement our client’s lifestyles and budgets.

Our Services

We live and work here in the outer western suburbs of Sydney and specialise in delivering customised designs and high-quality workmanship to help you to maximising your home floor area.

Increase your Space With:

Additional Bathrooms
More Bedrooms
Increase Garage Space
Larger Kitchens
Single Storey Additions
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Second storey additions

Increase living space while saving yard space by adding second storey addition.

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Ground Floor Additions

Maximises the available living space with a ground floor addition.

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Renovations

Upgrade your home with renovations that improve functionality and value.

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Why Choose Us?

Built on Over 30 Years of Experience

A second storey adds an entirely new dimension to your home, opening up a world of opportunity to accommodate for your lifestyle. Here’s why people choose Keystone to complete their second storey addition.

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Built On Time & Budget

We’re committed on completing your build on time and within budget.

Stay Home While We Build

Most clients stay in their homes during construction, no need to pay for rent or storage.

Disruption Kept to a Minimum

We keep noise, mess, & intrusion low, cleaning up daily and protecting your living space.

Customer-First Approach

We design with your lifestyle in mind and keep you involved every step of the way.

No Hidden Costs

Clear, detailed pricing in your contract—no surprises or unexpected charges.

Trusted Family Business

We’ve delivered quality second storey additions since 1997 with honesty and care.

Featured Projects

EXPLORE PROJECTS

Lilydale

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Julia

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Kan

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Verdi

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Clarke

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Malonga

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River

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Our Refined Process

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Free introductory session

A phone call where we get to know you, talk about your ideas, budget and goals.

Free Design Consultation

Site visit by our consultant who will sit down with you to address every concept of your proposed build.

Formal Concept Design and Proposal

Concept plan prepared by a Building Designer and formal proposal prepared.

Plans and Approvals

Detailed plans prepared and submitted to relevant authority for assessment and approval.

Preparing to Extend

We prepare you for the construction phase.

Construction Phase

This is when the real work begins – it’s time to turn your dream home into a reality!

Free introductory session

A phone call where we get to know you, talk about your ideas, budget and goals.

Free Design Consultation

Site visit by our consultant who will sit down with you to address every concept of your proposed build.

Formal Concept Design and Proposal

Concept plan prepared by a Building Designer and formal proposal prepared.

Plans and Approvals

Detailed plans prepared and submitted to relevant authority for assessment and approval.

Preparing to Extend

We prepare you for the construction phase.

Construction Phase

This is when the real work begins – it’s time to turn your dream home into a reality!

5.0
40 REVIEWS ON GOOGLE

Our Happy Customers

  • "To everyone who is reading this with intention to build a first floor addition, your search should end here.”
    Andrea
    NSW
  • "Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
    Tracey, Jason, Liam & Mackenzie Brown
    NSW
  • “All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
    Cathy & Stephen Bone
    NSW
  • "Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
    Reginald Moodley
    Penrith
  • "The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
    Neil Moodley
    Glenmore Park
  • "The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
    Chris and Jim
    Harrington Park
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
"Their workmanship is second to none that I have seen and the service and tradespeople they used were fantastic."
Reginald Moodley
Penrith
"The staff was very friendly and kept our premises spotless and clean. Nothing was too difficult or out of their way. "
Neil Moodley
Glenmore Park
"The whole process was professional, on time and on budget. The tradesmen were all brilliant and meticulous.”
Chris and Jim
Harrington Park
"To everyone who is reading this with intention to build a first floor addition, your search should end here.”
Andrea
NSW
"Thank you so much for all your dedicated hard work and especially your consideration to our family during the renovation of our home.”
Tracey, Jason, Liam & Mackenzie Brown
NSW
“All the tradesman involved in the renovation process were prompt, courteous and very meticulous.”
Cathy & Stephen Bone
NSW
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Before & After

Your Home, Transformed

A second storey doesn’t just add space—it changes everything.

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BEFORE
AFTER

Latest Insights

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5 Reasons Why A Second Storey Addition Is A Great Option

Residential real estate is becoming more and more expensive as time goes on and it’s certainly not looking like abating any time soon. So what do you do if you’re already a homeowner but you need more space?
READ MORE

Lessons Learned From The Sydney Housing Market

As Sydney house prices have continued to skyrocket over the past 15 years, many homeowners are deciding not to sell and be creative with their current living arrangements. Here are 6 lessons that can be learned from the recent house
READ MORE

How To Survive A Major Home Renovation

Almost everyone knows someone who’s undergone a major home renovation and regrets some mistakes that were made along the way. While the final product of a major home renovation can feel like a dream come true, the journey to get
READ MORE
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FAQs

Find answers to the most common questions you may have.

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What hours do the tradespeople generally work on my home?

Our team will usually be there between 7-7.30am and 3.30-4pm depending on the work being completed. If we need to access your home during times when you may be at work, we will discuss this with you to ensure a safe solution.

‍

What areas do you build in?

Keystone Home Additions are based in Penrith but have completed projects throughout the Sydney region.

‍

How soon can work on my project start?

Once council approval has been received and contracts have been signed we can generally start work in approximately 4 weeks however this will be confirmed as we approach this stage of the project.

‍

Will the extension blend in with my existing house?

We offer stylish designs made to seamlessly blend in with your existing home. Keystone consultants will present you with examples of before and after images to give you full confidence in the final outcome. You can see some of them HERE

‍

Can I still live in my home during construction?

For 95% of our projects, yes you can still live in your home during construction. Keystone commits to keeping your home clean and secure. We will make every effort to keep the disruption to an absolute minimum so you can stay in your home as we build but there will always be some dust, dirt and noise. Our friendly tradesmen use drop sheets and clean up after themselves at the end of every day’s work.

‍

How long will it take to build my extension?

On average it takes from 2 months to 5 months but can take longer, depending on the size of your addition. No matter how big the job, Keystone gives you a precise and fixed build time bound by a contract with penalty clauses.

‍

Who can I talk to during construction if I have any questions?

Our Project Manager is readily available to answer any questions and will also visit you and phone you for decision making and to keep you updated. You will also have their phone number to call if you have any questions.

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Do you have any guarantees?

Yes, Keystone has a number of unique guarantees to give you greater peace of mind. Get in touch to find out more.

‍

Do you give references from other completed projects?

Yes, we always give you a reference along with a list of previous work for you to drive by and look at.

‍

Do we need to arrange design and plans for council approval?

No, Keystones Building Consultants can assist you with the design and our draftsman will prepare the plans for council approval. However, if you already have an architect we are happy to work with them to complete the project.

‍

Can Keystone arrange Engineering drawings and Council Applications?

Yes! Keystone can take care of every aspect of the design and building process including engineering drawings and appropriate approvals.

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Start Your Home Transformation

Your first consultation and quote are on us!

REQUEST A QUOTE