Lempars Creations
Lempars Creations is an independent app development studio building practical tools for tradespeople and small businesses. Our apps are built by people in the trade — for people in the trade.
Apps
BOB The Estimator
BOB The Estimator is a purpose-built estimating app designed specifically for carpenters and small builders. BOB takes the guesswork out of pricing your jobs — building accurate, professional estimates and material lists based on your own rates, directly from your phone or tablet whether you're on-site or back in the office.
Too many tradies are either under-pricing jobs and leaving money on the table, or spending hours at the desk trying to pull numbers together from memory and rough notes. BOB was built to fix both of those problems. Enter your materials, labour and margins the way you actually work, and let BOB do the maths.
The app is built around real carpentry workflows. From framing and roofing through to fit-out and finishing, BOB lets you itemise every part of a job quickly and confidently. Generate clear, professional estimates that you can send straight to your clients — no more scribbling numbers on the back of an envelope, and no more pricing from gut feel and hoping for the best.
Alongside the estimating tools, BOB features a full suite of on-site calculators built for the way carpenters and builders actually work:
- Rafter Calculator — covers full roof geometry including HAP (Height at Plate), bird's mouth, ridge shortening, and both plumb and level cuts. Everything you need to frame a roof, right there in your pocket.
- Pitch Calculator — enter any two of rise, run, or pitch angle and BOB calculates the third. Simple, fast, and accurate every time.
- Right Angle Calculator — square any corner on-site without the mental gymnastics. Enter your measurements and BOB confirms your diagonal, keeping your work true from the start.
- Stair Calculator — work out your rise heights and quantities of stair materials quickly and accurately, so you can price and build stairs with confidence.
- Concrete Calculator — calculate concrete quantities for any pour so you're ordering the right amount every time — no costly over-orders or frustrating shortfalls.
- Volume Calculator — work out volumes for any part of a job where you need to know cubic quantities fast.
- Markup & Margin Calculator — understand the real difference between markup and margin percentage so you're always pricing for actual profit, not just covering costs.
Whether you're pricing a small renovation or a full residential build, BOB gives you the tools to estimate faster, price smarter, and run a more profitable trade business.
🎯 Our Goal with BOB
Tradespeople are some of the hardest-working people on the planet — but too many are losing hours in productivity or spare time simply because estimating is slow, confusing, or just never taught on the tools. BOB The Estimator exists to change that.
We aim to reduce the time spent on estimating to help you get back your evenings with the family, and increase productivity on-site with our range of handy calculators. Estimates first, quotes later — because a job priced confidently starts long before the paperwork does.
Our goal is to put a professional-grade estimating tool in the hands of every carpenter and small builder, regardless of their paperwork experience. We want tradies to finish a job site conversation and have a solid estimate ready before they've driven off the driveway. When tradespeople price confidently, they build sustainable businesses — and that's better for everyone.
Frequently Asked Questions
About Us
🏗 Lempars Creations
Lempars Creations is an independent software and app development studio focused on building practical, no-nonsense digital tools for the building and construction industry. We design our products from the ground up — by people who understand what life on the tools actually looks like.
Our products are built to be simple, reliable, and genuinely useful in the real world — not just impressive on a spec sheet.
👤 The Developer
Lempars Creations is operated by a working carpenter and small builder based in Victoria, Australia, with over a decade of hands-on experience across residential construction and custom carpentry. The frustrations of quoting, estimating, and running a small trade business first-hand are exactly what drove the creation of BOB The Estimator.
The goal is simple: build tools that actually solve real problems for real tradies.
⚖ Company & Legal Notice
Lempars Creations is a registered developer name operating under Parsons Custom Carpentry Pty Ltd (ACN available on request). Parsons Custom Carpentry Pty Ltd is the registered Company and Organisation behind Lempars Creations. All business dealings, agreements, correspondence, and enquiries relating to Lempars Creations and its products are conducted by and handled through Parsons Custom Carpentry Pty Ltd. For all contact and legal matters, please direct enquiries to Parsons Custom Carpentry Pty Ltd via the contact details provided on this website.