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Plumbing Calculators

Calculate drainage slopes, Hazen-Williams PSI drops, BTU recovery rates, and water heater sizing limits.

Gas Appliance Altitude Derating Calculator

Calculate the precise minimum nameplate BTUH required to safely heat a structure at high elevations due to thin, oxygen-poor air. Based on the National Fuel Gas Code (NFGC).

3-Piece Bathroom Rough-In Estimator

Estimate supply lines, drain pipes, and fittings for a standard toilet, sink, and shower rough-in using IPC pipe sizing rules.

BTU to GPH Recovery Estimator

Calculate a water heater's recovery rate in Gallons Per Hour (GPH) from its BTU input rating, thermal efficiency, and temperature rise. Covers gas, electric, heat pump, and tankless water heaters with fixture demand reference tables.

Commercial Water Heater Recovery

Launch the Commercial Water Heater Recovery tool to calculate accurate results.

Expansion Tank Sizing

Launch the Expansion Tank Sizing tool to calculate accurate results.

Fire Sprinkler K Factor Flow Rate

Launch the Fire Sprinkler K Factor Flow Rate tool to calculate accurate results.

Gas Branch Sizing

Launch the Gas Branch Sizing tool to calculate accurate results.

Gas Diversity Factor

Launch the Gas Diversity Factor tool to calculate accurate results.

Gas Pipe Sizing

Launch the Gas Pipe Sizing tool to calculate accurate results.

Gas Purge Volume

Launch the Gas Purge Volume tool to calculate accurate results.

Gas Vent Sizing

Launch the Gas Vent Sizing tool to calculate accurate results.

Grease Interceptor

Launch the Grease Interceptor tool to calculate accurate results.

Grease Trap Sizing

Launch the Grease Trap Sizing tool to calculate accurate results.

Hammer Arrestor

Launch the Hammer Arrestor tool to calculate accurate results.

Hazen Williams Friction Loss

Launch the Hazen Williams Friction Loss tool to calculate accurate results.

PEX-A vs PEX-B Flow Restriction Calculator

Analyze the massive friction loss and velocity spikes caused by insert-style PEX-B crimp fittings, compared to full-port PEX-A expansion joints.

Pipe Buoyancy

Launch the Pipe Buoyancy tool to calculate accurate results.

Pipe Freeze Protection Heat Trace Sizing

Launch the Pipe Freeze Protection Heat Trace Sizing tool to calculate accurate results.

Commercial Pipe Hanger Point Load Calculator

Calculate the exact dead-weight point load applied to threaded rod and clevis hangers by commercial steel and PVC piping completely filled with fluid.

Pipe Insulation Heat Loss & Savings Calculator

Model the thermodynamics of bare pipe vs insulated pipe. Calculate hourly BTU thermal transfer to determine the exact energy savings of pipe jackets.

Pipe Sloping / Pitch Tool

Calculate the total vertical drop required for horizontal plumbing waste lines to properly drain using 1/4 or 1/8 inch per foot gravity methods.

Pipe Thermal Expansion Calculator

Calculate the exact linear growth of steel, copper, or PVC pipes under thermal stress. Ensure your expansion loops and hanger brackets are sized correctly to prevent catastrophic pipe buckling.

Water Pipe Velocity Limit Calculator

Calculate exact fluid velocity (FPS) inside Copper, PEX, and PVC pipes to prevent water hammer and code violations.

Pipe Volume & Weight Calculator

Calculate the internal capacity (gallons) and structural water weight (lbs) inside a pipe system for engineering and hydro-testing.

GPM to PSI Pressure Drop Calculator

Use the Hazen-Williams equation to calculate water pressure friction loss through PEX, PVC, or Copper pipes based on flow rate (GPM), interior size, and run distance.

Propane Vaporization Rate Calculator

Estimate the maximum continuous withdrawal rate (BTUH) from propane tanks based on size, liquid level, and ambient temperature.

PRV Flow & Pipe Velocity Calculator

Calculate water pipe fluid velocity (FPS) and Pressure Reducing Valve (PRV) pressure drops based on peak GPM demand and actual internal pipe diameters.

Hydronic Radiant Floor Loop Estimator

Estimate PEX tubing, manifold zones, and loop requirements for in-floor radiant heating systems based on layout area and tube spacing.

Radiant Floor Loop Sizing Calculator

Calculate total PEX linear footage and manifold port requirements for hydronic radiant floor heating systems based on square footage and tube spacing.

Hydraulic Ram Pump GPD Estimator

Estimate the Gallons Per Day (GPD) yield of a zero-electricity hydraulic ram pump analyzing supply flow, drive fall, delivery lift, and mechanical efficiency.

Hot Water Recirculating Pump Sizer

Determine the exact GPM and head pressure requirements for a dedicated hot water return line. Factor in thermal pipe heat loss, insulation, and allowed temperature drop.

Rolling Offset Geometry

Launch the Rolling Offset Geometry tool to calculate accurate results.

Stormwater Roof Drain & Scupper Sizing Calculator

Calculate the stormwater runoff GPM from any roof area and rainfall intensity, then find the minimum IPC-compliant vertical PVC drain or scupper pipe size required.

Roof Scupper Sizing (Weir Flow) Calculator

Calculate the minimum required width for roof scuppers using the standard weir flow formula. Factors in catchment area, primary drainage flow, and secondary emergency overflow requirements per IPC code.

RPZ Backflow Pressure Loss Calculator

Calculate specific hydraulic pressure drops across Reduced Pressure Zone backflow preventers to verify downstream flushometer code compliance minimums.

Septic Tank & Leach Field Sizing Estimator

Estimate required septic tank volume and calculate drain field trench requirements based on home bedroom count and soil percolation absorption rates.

Septic Tank Buoyancy & Floatation Calculator

Calculate upward buoyant force on empty septic tanks to prevent flotation in high water tables. Determine the exact ballast weight required for code compliance.

Horizontal Storm Drain Sizing Calculator

Size horizontal storm drain pipes per IPC standards, including effective catchment area for roofs and vertical walls.

Commercial Sump Basin & Float Active Sizing

Correlate pump GPM and pit diameter into exact vertical float tether separation boundaries to hit strict motor cycling goals.

Sump Pit Inflow & Discharge Rate Calculator

Calculate true groundwater inflow rates and total continuous sump pump discharge capacity (GPM) using simple pit diameter timing tests.

Sump Pump TDH & Horsepower Sizing Calculator

Estimate Total Dynamic Head (TDH) including static lift and precise pipe friction to select the perfectly sized submersible sump or sewage ejector pump.

Sump Pump Tdh

Launch the Sump Pump Tdh tool to calculate accurate results.

Thermal Expansion Loop

Launch the Thermal Expansion Loop tool to calculate accurate results.

Potable Expansion Tank Sizing Calculator

Calculate the required thermal expansion tank volume for closed-loop water heaters based on tank capacity, city pressure, and standard 100°F temperature rise.

Pipe Thermal Expansion & Loop Sizing Calculator

Calculate linear thermal expansion for PVC, CPVC, PEX, and Copper pipes and determine exact dimensions for ASME-compliant expansion loops and flexible offsets.

Trench Excavation & Bedding Sand Sizing

Isolate the precise cubic yardage required for civil utility pipe trenching, utilizing exact mathematical pipe displacement metrics to guarantee flawless stone/sand bedding orders without costly mass overruns.

Vacuum Drainage System Sizing Calculator

Calculate specific Drainage Fixture Unit (DFU) network loads to dynamically right-size EN 12109 vacuum pipe diameters and prevent sewage stalling.

Water Heater Sizing (First Hour Rating)

Calculate your exact household Peak Hour Demand to definitively size residential and commercial water heaters based on First Hour Rating (FHR) science.

Main Water Service Pipe Sizing (WSFU)

Determine your exact commercial or residential water service pipe size by converting Water Supply Fixture Units (WSFU) into peak GPM volume while strictly maintaining safe maximum FPS velocity limits to prevent copper erosion.

Submersible Well Pump Sizing (TDH & GPM)

Select the correct residential well pump by mathematically resolving fixture Peak Demand for target GPM flow and graphing well lift physics to map Total Dynamic Head (TDH).