Studio 4, 118 Beaufort Street, Mount Lawley WA 6050 Monday to Friday 7:00am – 5:00pm
Registered Perth builder
Extensions that look like they were always there.
Mount Lawley · 2025
We build extensions, renovations and rebuilds across the Perth metro area — and nothing else. Every job is drawn against the house that is already there, priced as one fixed number, and run by the supervisor whose mobile you have.
Rear extension and open-plan kitchen, Mount Lawley
A 1930s brick-and-tile on a narrow Mount Lawley block, four people and one bathroom. The front rooms were the reason they bought the house and the reason they would not knock it down. The back half was a lean-to kitchen and a laundry you had to walk outside to reach.
“We had three builders quote the extension. Karri were the only ones who told us what would not work and why. They finished a week early and the price never moved.”
Rebecca T. · Mount Lawley
01What we build
Four jobs, done properly, instead of everything done once.
A builder running new estate homes, commercial fit-outs and heritage renovations at the same time is running three businesses with one set of trades. These are the four we are good at.
The test is whether you can pick which part came later.
Duncraig, 2025. A flat aluminium patio bolted to the fascia, replaced with a gable that continues the existing roof at the same pitch, in the same tile.
Before — 1990s patioAfter — 2025 alfresco
Drag the handle, or use the arrow keys, to compare.50% builtThe Duncraig house before work started, with a flat aluminium patio attached to the rear.
Matching the existing roof mattered more than the budget saved by not matching it. The gable continues the main roof pitch at 25 degrees in the same tile profile, so from the back garden the house reads as one building.
Most additions look added because nobody drew them against the original. Brick, roof pitch, eave depth and window proportion decide whether the join disappears, and those get resolved on paper before a price exists.
Fig. 03 — existing footprint, new work hatched
01
Design against the house that is already there
Brick selection, roof pitch, eave depth and window proportion decide whether an addition reads as original or as an afterthought. We draw those against the existing house before we draw anything else.
02
Find the problem on paper, not on site
Services, levels, structure and planning constraints get investigated before the price is fixed. It is slower at the start and it is the reason our contract prices hold.
03
One builder, first sketch to final clean
You deal with the same person throughout. We run a set number of sites at once so the supervisor is genuinely on yours rather than driving between six.
04The process
One price, five stages, and a date attached to each of them.
A builder who will not commit to a stage length is a builder who has not planned one. These are ours, including the stage that is not in our control.
Drawings, engineering, and one number that does not move.
Duration
Four to eight weeks
Cost
Design fee, credited against the build if you proceed
03
Approvals
We lodge it, we chase it, we tell you where it sits.
Duration
Two to twelve weeks, set by your local government
Cost
Inside the contract
04
Build
One supervisor, one contact, a photo update every Friday.
Duration
Five weeks to fourteen months, depending on the job
Cost
Progress claims against the fixed-price contract
05
Handover and the six-month check
Defects closed out, then we come back and look again.
Duration
Handover in a day. The check is at six months.
Cost
Inside the contract
05Selected projects
Documented, dated and priced — not a gallery.
Every project here lists the suburb, the time on site, whether the contract price held and whether the owners stayed in the house. Those are the four things people actually want to know.
Tom served his carpentry apprenticeship in Fremantle, spent nine years working on character homes across the western suburbs, and registered as a builder in 2008.
He is on every site visit, writes every fixed-price contract, and is the person who tells clients when their idea will not work. That last part is why the business exists in the shape it does — it was the thing he could never do properly working for someone else.
“The best compliment we get is when someone asks which part of the house is the new bit and gets it wrong.”
4.9 out of 5 across 87 Google reviews. The ones below are attached to the builds they came from.
“We had three builders quote the extension. Karri were the only ones who told us what would not work and why. They finished a week early and the price never moved.”
Rebecca T.Mount Lawley · Two-storey rear extension, 2025See this build
“We lived in the house through the whole renovation with two kids. They kept it sealed off, cleaned up every single day, and always told us what was happening the following week.”
Daniel M.Fremantle · Full cottage renovation, 2024See this build
“Six months after handover they came back, went through everything and fixed two small things without being asked. We have not had that from a builder before.”
Priya S.Duncraig · Alfresco and outdoor kitchen, 2025See this build
“Eleven months is a long time to trust somebody with that much money. We got a photo update every Friday for every one of those weeks, including the ones where it rained and nothing happened.”
Michael C.Scarborough · Knock-down rebuild, 2024See this build
“The feasibility report talked us out of a rebuild and into an extension. It cost us a fraction of what we were about to spend, and they were the ones who said it.”
James & Hannah W.Bayswater · Feasibility, then a ground-floor addition, 2024
08Book a site visit
An hour at the house, and an honest answer.
You get an honest read on whether the idea stacks up — including when it does not. Talking someone out of the wrong job costs us a quote and saves them a year.