· 3 min read
How Much Grass Seed Do I Need? Seed Rate by Lawn Area
Work out how much grass seed to buy from your lawn area and the seed rate — with different rates for a new lawn versus overseeding.
Articles by Marco Bianchi
Home, DIY & motoring writer · View profile
· 4 min read
The Perfect Coffee-to-Water Ratio (the Golden Ratio Explained)
The golden ratio is roughly 1:16 — learn grams of coffee per cup and how to adjust strength to your taste.
· 2 min read
What Affects an Electric Car's Range?
Battery size, efficiency, speed, cold weather and terrain all move an EV's real range far from the sticker figure. Here's how each factor works.
· 3 min read
How Many Bricks Do I Need? Calculate Bricks Per Wall
Estimate bricks for any wall from its area, a per-square-foot brick count, and a waste allowance — so you buy once and avoid a second trip.
· 3 min read
How Many Solar Panels Do I Need? A Simple Sizing Method
Size a solar array from your annual electricity use, panel wattage, and local sun hours — plus a quick payback estimate in dollars.
· 4 min read
The Right Rice-to-Water Ratio for Every Type of Rice
Learn the exact water ratio for white, brown, basmati and jasmine rice using the absorption method — no measuring guesswork.
· 14 min read
Engine Displacement and Compression Ratio: What They Actually Tell You
Both numbers are pure geometry — one is the volume a piston sweeps, the other a ratio of two volumes — and both are read as if they described power. Here is each derivation worked on real engines, and exactly what each number can and cannot support.
· 13 min read
Tyre Tread Depth: the Legal Limit Is Not the Safe Limit
The legal minimum exists to define an offence, not to describe a safe tyre. Tread does one job — getting water out of the contact patch — so its effect is near zero in the dry and decisive in the wet. Here is what the numbers say, and how to measure your own.
· 12 min read
The Real Cost of a Trip Is Not the Fuel
Comparing a drive with a train ticket on fuel alone understates the car by a factor of five. Here is how to build the marginal cost of a trip, how to separate it from the fixed cost of ownership, and why both numbers are correct answers to different questions.
· 11 min read
What a Car's CO2 Figure Actually Measures
A car's CO2 number and its fuel consumption number are the same measurement in different units, tied together by chemistry that you can do on paper. Here is the derivation, and then the three things the figure quietly leaves out.
· 2 min read
How Much Paint Do You Need to Paint a Room?
Estimate paint by wall area, coats and the coverage on the tin — with a worked example and the 10% rule so you buy once and match the colour.
· 3 min read
How Many Tiles Do You Need? (Floor and Wall)
Estimate tiles from the area to cover and one tile's size, then add for cuts and waste. Here's the method, with an example and the 10% rule.
· 3 min read
Cooking Measurement Conversions
A few anchors — cups, tablespoons, grams — cover most recipes. Here's the handful worth memorising, why weight beats volume, and when to reach for a scale.
· 3 min read
What Size Air Conditioner Do I Need?
Around 20 BTU per square foot is the starting rule. Here's how to size a unit from your room's area, adjust for sun and use, and why bigger isn't better.
· 3 min read
How Much Flooring Do You Need? (With Waste)
Divide the room's area by a pack's coverage, then add for cuts and waste. Here's the method, with an example and how much extra to buy.
· 3 min read
Lease vs Buy a Car
Leasing means lower payments but no ownership; buying costs more per month but the car is yours. Here's how each works and which fits your situation.
· 3 min read
How Much Mulch Do I Need?
Multiply the bed's area by the depth you want. Here's the volume formula, how deep to spread it, bags vs bulk, and the cubic-yard version.
· 3 min read
How Much Wallpaper Do You Need?
Measure the wall area, divide by a roll's usable coverage, then add for pattern repeat. Here's the method, with an example and why batch numbers matter.
· 3 min read
How Much Concrete Do You Need?
Concrete is measured by volume: length × width × depth. Here's how to work out cubic metres, add for waste, and choose bags or ready-mix.
· 3 min read
Fuel Cost for a Road Trip
Divide distance by fuel economy, then multiply by the price. Here's the calculation, metric vs mpg, what pushes it up, and how to split the cost.
· 3 min read
How to Calculate the Square Metres of a Room
Find a room's area by multiplying length by width. Here's the method for rectangular, L-shaped and round rooms, and why area drives your material orders.
· 3 min read
How Much Gravel Do I Need?
Multiply area by depth for a volume, then convert to weight — gravel is about 1.5 tonnes per cubic metre. Here's the method, depths by job, and how to order.
· 3 min read
What Is MPG (and How to Improve It)?
MPG is how far a car goes on a gallon — higher is better. Here's what it means, how it relates to L/100 km, why your real figure is lower, and how to improve it.
· 3 min read
How to Scale a Recipe Up or Down
Multiply every ingredient by the same factor. Here's how to find it, why the ratios must stay fixed, what doesn't scale linearly, and how to round sensibly.