Water Heater Sizing Calculator
Estimate the tank size (gallons) and recommended first-hour rating for a household water heater, based on the number of...
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Estimate the tank size (gallons) and recommended first-hour rating for a household water heater, based on the number of...
Compute how many pounds of bagged fertilizer to spread on a lawn for a target nitrogen rate (lb of N per 1000 ft²) given...
Compute the run, hypotenuse length, and slope ratio of a wheelchair ramp from the rise (the height it must overcome). Th...
Compute the number of 2-cubic-foot bags of mulch you need to cover a garden bed at a target depth, given the bed's lengt...
Estimate the BTU/hr capacity needed to heat or cool a room from its area and a climate-zone factor (10–60 BTU/ft² for he...
Compute the number of bags of garden soil needed to fill a raised bed of a given length × width × depth, with a 5% over-...
Convert a BTU/hr cooling load into air-conditioner tonnage (1 ton = 12,000 BTU/hr) and round up to the nearest standard...
Estimate the minimum septic tank capacity required by typical residential code, based on the number of bedrooms (each be...
Estimate the generator size you need from total running watts and the largest motor's starting (surge) wattage. Picks th...
Estimate the number of 80-lb (or 60-lb / 40-lb) ready-mix concrete bags needed to pour a slab of length × width × thickn...
Compute the required HVAC airflow in cubic feet per minute (CFM) for a room from its volume and the target air changes p...
Convert a wood pile's length × height × depth into the equivalent number of full cords (128 ft³) and face cords (typical...
Estimate the pounds of grout needed for a tiled area, based on the tile size, grout joint width, and grout joint depth.
Compute the ounces of 65% calcium hypochlorite (cal-hypo) needed to raise the free chlorine in a pool by a target ppm.
Estimate the dehumidifier capacity in pints per day required for a basement or room, based on its square footage and how...
Compute the round duct diameter in inches required to carry a given airflow (CFM) at a chosen design velocity (typically...
Compute the length of a roof rafter and the pitch ratio (rise per 12 inches of run) from the run and rise of the roof.
Compute the yards of fabric needed to make curtain panels for a window from the window width, panel length, fabric width...
Compute the inches of insulation you need to add to reach a target attic R-value, given the insulation's R-per-inch and...
Compute the required ventilation airflow (CFM) for a room from the room volume and a target air-changes-per-hour (ACH) f...
Compute the heat lost through a window in BTU per hour from its U-value, area, and the indoor-outdoor temperature differ...
Estimate how many garments your closet rod can hold based on its length and the average inches needed per garment (1 in...
Compute the number of boxes of laminate, vinyl, hardwood, or tile flooring needed to cover a room, given the room area,...
Compute the recommended viewing distance for a TV from its diagonal screen size in inches and its resolution. 4K TVs all...