Logo with the words "Granny Flats" in cursive script above "BY HALLMARK" in uppercase letters with a gold line underneath.
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Logo with the words "Granny Flats" in cursive script above "BY HALLMARK" in uppercase letters with a gold line underneath.

Modern Granny Flat in Mt. Lawley

A single-story red brick house with a tiled roof is surrounded by trees, bushes, and a grassy lawn in a garden setting.

Completed 2025

Mount Lawley

Modern Granny Flat in Mount Lawley — A Private, Stylish Backyard Retreat ✨

This beautifully finished granny flat in Mount Lawley is the perfect example of how smart design and quality craftsmanship can transform a backyard into a private, self‑contained home. Surrounded by established gardens and leafy Mount Lawley charm, this secondary dwelling offers comfort, independence, and modern living in one of Perth’s most sought‑after suburbs.

Inside, the open‑plan layout feels bright and welcoming, with a contemporary kitchen flowing into a cosy living area ideal for everyday relaxation. The bedroom is thoughtfully designed with clean lines, natural light, and generous storage, while the stylish bathroom features quality fixtures and a fresh, modern palette.

Whether you’re creating space for family, planning a rental opportunity, or adding value to your Mount Lawley property, one of our granny flats can deliver that perfect blend of practicality and lifestyle. It’s a standout example of how a well‑designed granny flat can enhance both your home and your investment.

A brick house with a sliding glass door opens to a garden with a brick path, trees, and a second building visible in the background.
A single-story brick house with a red-tiled roof, surrounded by trees, plants, and a well-kept lawn in a fenced yard.
Single-story brick house with a red tile roof, surrounded by trees, shrubs, and a green lawn under bright sunlight.
Modern bathroom with walk-in shower, glass partition, white vanity, wall-mounted toilet, towel rail with two towels, washing machine, and a window above the shower area.
Modern bathroom with a glass-enclosed shower, green vertical tiles, white vanity, wall-mounted mirror cabinet, and a towel hanging near the window.
A bedroom with a double bed, wooden headboard, two bedside tables, mirrored wardrobe doors, white walls, and a small window above the bed.
A bedroom with a double bed, wooden headboard, two bedside tables, sliding glass doors with sheer curtains, and two small windows above the bed.
A wall-mounted wooden bookshelf with three shelves holding books, a small glass bottle, and a decorative arrangement of dried flowers.
Rectangular skylight in a white ceiling with tree branches and leaves visible through the glass.
Modern open-plan living area with kitchen island, beige sofa, TV, air conditioner, and decorated Christmas tree by the window; wood flooring throughout.
A living room with a beige sectional sofa, a TV on a wooden cabinet, a Christmas tree, a guitar, wood flooring, and a skylight.
Modern kitchen with white cabinets, a green island with two wooden stools, wood flooring, and a guitar resting against the wall. Sliding glass doors lead to an outdoor area.
Modern kitchen with white cabinets, a central island with two stools, and wood-style flooring. Glass door opens to outdoor area with greenery visible.
Modern kitchen with white cabinets, a refrigerator, electric stove, and small appliances on the counter; two stools at a white island, and a guitar against the wall.
Single-story brick house with a red tiled roof, screen door, outdoor lights, potted plant, and garden with shrubs and trees in the front yard.
A single-story red brick house with a tiled roof is surrounded by trees, bushes, and a grassy lawn in a garden setting.
View from a covered patio looking out onto a green backyard with plants, trees, a garden shed, and lawn bordered by a green fence.
Cursive text reading "Opening Flair by Hallmark.

Granny Flats by Hallmark are Perth’s Best Granny Flat Builder. Based in Clarkson (Perth) and building Granny Flats Across Perth’s Northern Suburbs. Locally Owned and Operated by Mark Gethin

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View our other Granny Flat Projects...

''Perth’s Best Granny Flat Builder''

Here at Granny Flats by Hallmark we are so thankful for the wonderful people we get to work with on a daily basis. Our reviews speak for themselves with our clients always speaking highly of us and the job we have done for them

  
 
 
 
 
 
 
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 Drew & Tamara Coulthard profile picture 
 
 
 Drew & Tamara Coulthard 
 
28 July 2025
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
We had a superb experience when Mark and his team built a custom designed garage and upstairs ancillary accommodation from our drafted plans.  The project was delivered quite quickly in a very tight access space with minimal disruption to our backyard.  Nothing was too much trouble as we changed a few things during the build.  The tradespeople were all lovely, trustworthy, quality and professional.  We would definitely look to Mark if we were to do a similar build again in the future.  Thank you team for a great experience and putting us at ease for what can be a very stressful exercise.
  
 
 
 
 
 
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 Elad Feldman profile picture 
 
 
 Elad Feldman 
 
28 July 2025
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
+5
Hallmark did a great job building our granny flat. Mark was fantastic to deal with—honest, reliable, and made the whole process easy. The build was high quality and finished on time. Would happily recommend them to anyone!
  
 
 
 
 
 
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 belinda o profile picture 
 
 
 belinda o 
 
28 July 2025
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
We couldn't be happier with the experience we had with Hallmark Developments for our home addition. From start to finish, their quality of work was outstanding, with every detail handled meticulously. Mark and his team were extremely professional, always keeping us informed and providing honest advice that made the process smooth and worry-free. They were also impressively prompt, completing the project on time without cutting corners. It's rare to find a company that combines such high-quality craftsmanship with transparency and efficiency. We highly recommend Hallmark Developments to anyone looking for a reliable and skilled builder!"
  
 
 
 
 
 
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 Fran profile picture 
 
 
 Fran 
 
26 June 2025
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
Had Mark build a large custom granny flat, from start to finish was amazing. Nothing was an issue and easy to work with.
Highly recommend build to anyone thinking of putting an addition on their property Thank you mark wonderful job!
  
 
 
 
 
 
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 Murray Woodington profile picture 
 
 
 Murray Woodington 
 
2 April 2025
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
Outstanding experience.  From 1st consultation to handover we've been more than impressed with the first class service and attention to detail delivered by Mark and the team.
We now have two amazing spaces to enjoy the wonderful West Oz lifestyle.
  
 
 
 
 
 
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 Lolly Evans profile picture 
 
 
 Lolly Evans 
 
2 October 2024
 
 
 Google star 1Google star 2Google star 3Google star 4Google star 5Trustindex verifies that the original source of the review is Google. 
A personalized, professional experience during these build works from Mark and his team. What we thought would be a nightmare at the back yard with noise, drilling, digging and more, turned out to be a fun experience with his team as we communicated, chatted, drank coffee or tea on the freezing days and just shared opinions about the growth of the works as they happened.

Mark and team were always open to suggestions and feedback as works progressed, and this made the entire experience smooth running, to deadline, with a super quality finish, exceeding our expectations.. Thanks Hallmark!. Well done- John and Lauretta.

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Modern house exterior with brick and white walls, large windows, and illuminated lights. A tiled porch leads to glass sliding doors.

Take a look at our range of thoughtfully designed granny flats, made to suit Perth families, investors, and homeowners alike. We specialise in Custom Designed Granny Flats so every design can be personalised to your liking. 

Our Granny Flat Designs
Spacious bedroom with sloped ceiling, large window, and glass doors. Contains a bed, sofa, armchair, floor lamp, and a pendant light. Neutral tones and minimal decor.

See the real results we've delivered across Perth. From sleek finishes to clever use of space, our completed builds show the quality and care that goes into every granny flat we construct. Let these transformations inspire your own backyard project.

Our Finished Projects
Modern single-story house with large glass doors, flat roof, and exterior lighting. A small rectangular garden bed with shrubs is in the foreground, surrounded by a paved patio area.

There’s a lot that goes into building a granny flat but you don’t need to worry about that. We handle the big stuff like council approvals, design, and construction so you can focus on the exciting part! Here's what to expect when building a granny flat with us. 

Our Process