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Second Storey Additions

When your home has outgrown its footprint but the street, schools and neighbours still feel right, a second storey addition lets you build upward instead of moving on. Also called a second storey extension or first floor addition, this style of home renovation adds a whole new level of bedrooms, bathrooms and living areas above your existing home, no backyard sacrificed.

second storey additions

Higher Energy Efficiency

Modern ground floor extensions use high-performance glazing, cross-ventilation, and quality insulation to keep energy bills low year-round.

Add Views and Light

Elevated rooms draw in natural light, afternoon breezes and rooftop outlooks you cannot get at ground level.

Get More Privacy

Lift master bedrooms, studies and guest rooms upstairs to free the ground floor for relaxed communal living.

Boost Property Value

Near-doubling your usable floor area is one of the most reliable ways to lift long-term equity and resale value.

More Living Space

When a growing family, a work-from-home routine or an ageing parent stretches your current layout, relocating is rarely the most sensible answer. Once you add stamp duty, agent fees, removalists and Sydney’s scarce land supply, staying put and building up almost always comes out ahead on both lifestyle and finances.

A second storey extension turns your existing footprint into a full two-level home, typically adding three to five new rooms above your ground floor while leaving the yard untouched. It is a customised alternative to a full knock-down rebuild, preserving the character of your home along with the trees, fences and landscaping you have built up over years. Compared to ground floor extensions that use more of your block, building up delivers more space, more privacy and more property value from a single project.

At Keystone Building, second storey additions and first floor additions are our daily work across Western Sydney, from Penrith, Kingswood, Cranebrook and Jamisontown through to Mulgoa, Wallacia, Wilberforce, Windsor, Dural, Seven Hills, St Marys, Orchard Hills, Claremont Meadows, Colyton, Leonay, Regentville, Londonderry and Llandilo. Our in-house team manages concept design, engineering, council applications and on-site construction, so one trusted builder carries you from the first consultation through to handover.

Pairing a new upper level with a ground floor refresh, such as an open-plan kitchen, a reconfigured entry or updated bathrooms, lifts both liveability and market value in one coordinated program. Whether you are future-proofing for a larger family or preparing to sell in five or ten years, this style of home renovation keeps paying you back in both new space and equity.

Feeling cramped in your own space?

Is your yard underused or impractical?

Not keen on extending upwards?

Before & After

Your Home, Transformed

A ground floor extention doesn’t just add space—it changes everything.

BEFORE
Modern two-story white house with a multi-gabled metal roof, large windows, a two-car garage, and a front garden with shrubs.
AFTER

"Keystone Building should be the Australian Standard for the construction and service industry. I would highly recommend this company to anyone looking to add to their home."

S. Courtis
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.

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.

Our Refined Process

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!

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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

Our trusted suppliers

Our long-standing relationships with reputable brands ensure that every project we deliver not only looks great but stands the test of time. By partnering with specialists in each product category, we’re able to offer you a wide selection, competitive pricing, and materials that meet Australian standards.

FAQs

Find answers to the most common questions you may have.

What Areas do you build in?

Keystone Home Additions are based in Penrith but we have completed projects through a large portion of the Sydney region.

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.

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.

info@keystonebuilding.com.au
02 4722 5466
Unit 1, 29 Coombes Drive, Penrith 2750
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