Sustainable Building Tools
Free calculators and planning tools for DIY eco homes, including insulation R-values, solar sizing, climate zones, and wall assemblies.
- R-Value Insulation Calculator — Live
Estimate nominal and effective wall R-values with thermal bridging, continuous insulation, climate-zone targets, and rough material costs. - Solar System Sizing Calculator — Live
Plan preliminary solar array, battery, and inverter sizes from household loads, autonomy goals, and off-grid design assumptions. - Building Climate Zone Lookup — Live
Look up building climate-zone guidance and the insulation, moisture, and mechanical-system priorities that change by region. - Wall Assembly Builder — Live
Compare wall assembly layers, insulation approaches, thermal breaks, and moisture-control notes before committing to a build detail. - Shed Insulation Calculator — Live
Estimate shed wall, roof, and floor insulation quantities with usage-based R-value targets, material ordering math, and ventilation warnings. - Insulation Cost and Savings Estimator — Live
Estimate annual heating and cooling savings, simple payback, energy reduction, and CO2 reduction from an insulation upgrade. - Passive House Cost Calculator — Live
Compare code-minimum and Passive House build scenarios with upfront premium, DIY discount, energy savings, payback, and 30-year total cost. - Air Sealing ROI Calculator — Live
Estimate annual heating and cooling savings, simple payback, and a prioritized leak hit-list from an ACH50 air-sealing project. - ERV/HRV Sizing Calculator — Live
Size whole-house balanced ventilation by ASHRAE 62.2, choose ERV or HRV by climate, and lay out duct size, local exhaust, and defrost recommendations. - Heat Loss Calculator — Live
Estimate whole-house design heat loss and right-size a heat pump using the simplified UA method, infiltration, climate design temperature, and component breakdown. - Window U-Factor Comparison — Live
Compare residential windows by U-factor, SHGC, and price; see annual heating cost, useful solar gain, summer cooling penalty, and payback vs a code-minimum baseline. - Embodied Carbon Calculator — Live
Estimate the upfront embodied carbon of a residential build by wall, roof, and foundation assemblies; compare alternatives and see car-mile equivalents. - Slab-on-Grade Insulation Calculator — Live
Estimate slab-on-grade perimeter heat loss with the ASHRAE F-factor method, compare insulation strategies, and see annual heating cost and payback vs an uninsulated baseline. - Cabin Material Calculator — Live
Estimate the materials and rough cost of a small cabin: lumber, sheathing, insulation, roofing, foundation, drywall, and openings — by footprint, height, and pitch. - Passive House Feasibility Quiz — Live
Score a residential design against PHIUS / PHI Passive House targets across airtightness, R-values, glazing, ventilation, and thermal bridges; get a gap analysis with concrete next steps.