John Telford Overview Formula 01What this calculator tells you A net-zero energy home generates as much energy on-site over a full year as it uses. This calculator puts the two sides of that balance next to each other: it estimates the annual generation from your solar array, compares it with your annual consumption, and returns a clear … Read more
Overview Formula 01What this calculator checks The Passive House (Passivhaus) standard is a performance-based way to design ultra-low-energy buildings. Rather than prescribing specific materials, it sets a small number of hard limits on how the finished building performs. This calculator takes the three headline figures a designer already has — annual space heating demand, primary … Read more
Overview Formula 01What this calculator estimates A home energy upgrade — insulation, air sealing, a heat pump, efficient windows or a smart thermostat — costs money up front but lowers your bills every year afterwards. This calculator turns that trade-off into four plain numbers: the annual bill saving, the simple payback in years, the ten-year … Read more
Overview Formula 01What this calculator tells you The U-value (thermal transmittance) of a wall, roof or floor is the rate at which heat passes through one square metre of it for every degree of temperature difference between inside and outside. It is measured in watts per square metre per kelvin (W/m²K), and lower is better … Read more
Overview Formula 01What this calculator estimates Every barndominium cost calculator on the market stops at a dollar figure. Before you can price a build accurately — or even sanity-check a supplier’s quote — you need an actual bill of materials: how many trusses, how many steel panels for the walls and roof, and how much … Read more
Overview Formula 01What this calculator estimates Barndominium cost quotes typically get boiled down to a single national range — $65 to $160 per square foot — that glosses over two of the biggest cost drivers: how much of your build is finished living space versus lightly-finished shop or garage space, and whether you are managing … Read more
Overview Formula 01What this calculator estimates Shipping container home costs get quoted as a single wide national range almost everywhere you look — $150 to $350 per square foot covers everything from a bare-bones single container to a fully custom multi-container house. This calculator turns your square footage, finish tier, foundation type, and regional cost … Read more
Overview Formula 01What this calculator sizes An off-grid tiny house has no utility to fall back on, so it needs three things sized correctly together: the solar array that generates enough power on a poor-sun day, the battery bank that stores enough energy to ride out a stretch of cloudy weather, and an inverter rated … Read more
Overview Formula 01What this calculator plans Building with shipping containers is a construction-planning problem before it is a cost problem: how many containers do you actually need, how will they be arranged, how much structural cutting is required to join them, and how long will it realistically take? This calculator turns your target square footage, … Read more
Overview Formula 01What this calculator estimates This calculator turns a single floor-area figure into a full construction and demolition (C&D) waste picture: the total tonnes generated, how that splits between material diverted from landfill (recycled or reused) and material sent to landfill, the number of skips you will need, and a rough landfill disposal cost. … Read more
