Decisions for the trades, not just numbers.

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Electrical (15)

Electrical Wire Size and Voltage Drop Pick a conductor size and material for a run, and know whether ampacity or voltage drop is really driving it. Electrical Breaker and OCPD Sizing Size the breaker for a load and its conductor, and see what the code rules actually require. Electrical Motor Circuit Sizing Size the conductor, overload, and branch protection for a motor from its horsepower and voltage. Electrical Ampacity Derating Adjust conductor ampacity for ambient temperature and bundled conductors, and see if the wire still carries the load. Electrical Grounding and Bonding Sizing Size the equipment grounding conductor by breaker, or the grounding electrode conductor by service size and electrode type. Electrical Backup Generator Sizing Size a backup generator for the loads you want to run, and compare essential, whole-house, and load-managed options. Electrical Service Load Calculation Estimate a dwelling service or feeder size with the NEC Article 220 standard method, as a planning sanity check. Electrical Transformer kVA Sizing Size a transformer in kVA from the connected load, phase, and voltages, with FLA and NEC primary protection. Electrical Voltage Drop Remedy Your run drops too much voltage. See the ways to fix it and which one makes sense. Electrical Conduit Fill Pick a conduit size for a bundle of conductors and see how much room is left for future pulls. Electrical Box Fill Figure the required box volume for your conductors and devices, and pick a box that fits. Electrical Conduit Bending Offset Lay out a conduit offset: distance between bends, shrink, and which bend angle to use. Electrical Pull and Junction Box Sizing Size a pull box for large conductors by NEC 314.28, for straight, angle, and U pulls. Electrical Parallel Conductor Sizing Size a large feeder as one conductor or parallel sets, with the NEC 1/0 rule and fill adjustment. Electrical EV Charger Circuit Sizing Size the wire and breaker for a Level 2 EV charger, and decide plug-in versus hardwired.

Plumbing (10)

Plumbing Water Pipe Sizing Size a water supply line so the far fixture still gets the pressure and flow it needs. Plumbing Drain Sizing Add up the fixtures and size a drain branch or building drain, with the water-closet and slope rules built in. Plumbing Drainage Slope and Fall Get the fall a horizontal drain needs, or check whether a slope meets code and is not too steep. Plumbing DWV Vent Sizing Size a plumbing vent from the stack diameter, the fixture-unit load, and the developed vent length. Plumbing Expansion Tank Sizing Size a thermal expansion tank from the water heater volume, temperature rise, and system pressure. Plumbing Sump Pump Sizing Size a sump pump from measured pit inflow and the discharge lift and run. Plumbing Water Heater Sizing Decide between a tank and a tankless water heater for your peak demand and climate. Plumbing Gas Pipe Sizing Size a natural gas line for the appliance load and run, with a plain warning that gas work is for a licensed pro. Plumbing Pipe Friction Loss Find the real pressure loss down a pipe run, fittings included, and whether the size holds up. Plumbing Well Pump Sizing Size a well pump from peak demand, well depth, pressure, and pipe run using total dynamic head.

HVAC (8)

HVAC HVAC Load Sanity Check Sanity-check a quoted air conditioner or furnace size before you commit, and know when you need a real Manual J. HVAC Duct Sizing Size a round duct for an airflow and see the velocity, with a quieter size up. HVAC Equipment vs Load Match Check whether an AC or heat pump size fits your load under the ACCA Manual S limits, or is oversized. HVAC Static Pressure Budget See how much static pressure your blower has left for the ducts after the filter, coil, and grilles. HVAC Refrigerant Line Sizing Pick the liquid and suction line size for a refrigerant run, and see when length or lift forces a change. HVAC Mini-Split Sizing Estimate the mini-split head size for a room from its area, climate, and conditions, without oversizing. HVAC CFM per Room Balance airflow to a room by its share of the load, and see how many supply registers deliver it. HVAC Grille and Register Sizing Size a supply register or return grille from its CFM, and pick the face velocity for quiet or compact.

Concrete (8)

Concrete Concrete Volume and Order Work out how much concrete a pour needs, then decide whether to bag it or order ready-mix. Concrete Rebar Quantity and Spacing Take off the rebar for a slab: bar count each way, linear feet with laps, and sticks to buy. Concrete Slab Thickness and Joints Pick a slab thickness and reinforcement for the use, then lay out control joints at the right spacing and depth. Concrete Concrete Mix (PSI) by Application Pick the concrete strength, air entrainment, and water-cement ratio for an application and climate. Concrete Footing / Pier Size Size a pad or continuous footing from the load and the soil bearing capacity. Concrete Concrete Cost Estimator Put in your prices and see the real cost of bagging a pour by hand versus ordering ready-mix. Concrete Concrete Bags per Project Get the concrete bag count for post holes, a slab, or tube forms, in every bag size. Concrete Concrete Steps Volume Get the concrete for a set of poured steps, in cubic yards and bags, with an optional base slab.

Roofing (6)

Roofing Roofing Squares and Waste Turn a roof footprint and pitch into squares and bundles, with the right waste for the roof. Roofing Roof Underlayment and Fasteners Get the underlayment rolls and roofing nails for a roof, and choose felt versus synthetic. Roofing Ridge Vent and Ice-and-Water Get the ice-and-water rolls for the eaves and the ridge-vent length and net free area. Roofing Attic Ventilation and Net Free Area Work out the attic vent area you need, split intake and exhaust, and decide between the 1/150 and 1/300 rules. Roofing Roof Pitch Converter and Walkability Convert a roof pitch to degrees, percent, and area multiplier, and judge whether it is walkable or needs jacks or staging. Roofing Gutter and Downspout Sizing Size gutters and downspouts from the roof drainage area and rainfall, and settle 5 in vs 6 in K-style.

Painting (1)

Painting Paint Coverage and Primer Work out gallons and coats, and whether you actually need primer for your surface and color change.

Drywall (1)

Drywall Drywall Sheets and Materials Take off drywall: sheets, joint compound, tape, and screws, and whether to run 4x8 or 4x12.

Flooring (1)

Flooring Flooring Coverage and Waste Turn a room area and layout pattern into flooring boxes to buy, with the right waste and attic stock.

Fencing (1)

Fencing Fence Materials and Post Spacing Turn a fence run and height into posts, rails, pickets, and concrete, and settle 6 ft vs 8 ft post spacing.

Landscaping (3)

Landscaping Mulch, Soil and Gravel Quantity Turn a bed area and depth into cubic yards and bags, and decide whether to buy bags or order bulk. Landscaping Grass Seed vs Sod Work out the grass seed or sod a lawn needs, and decide between seeding and sodding by cost and speed. Landscaping Gravel and Base Tonnage Turn an area and depth into cubic yards and tons of gravel, base, or sand to order.

Framing (6)

Framing Wall Framing and Stud Spacing Turn a wall length and height into studs, plate lumber, and sheathing, and settle 16 in vs 24 in stud spacing. Framing Stair Rise, Run and Risers Turn a floor-to-floor rise into a code-aware riser count, riser height, tread count, and total run. Framing Floor Joist Span Lookup Check whether a floor joist spans your opening, and see the lighter options that do. Framing Roof Rafter Length and Cuts Get the common-rafter length, the plumb and seat cut angles, and the stock length to buy. Framing Board Foot and Lumber Cost Get the board feet in your lumber and whether buying by the board foot or by the piece is cheaper. Framing Plywood and OSB Sheet Count Turn a wall, roof, or floor area into 4x8 sheets and the nails to fasten them.

Insulation (1)

Insulation Insulation R-Value and Material Choice Pick the insulation that hits your target R-value in the cavity depth you have, by cost or by space.

Excavation (1)

Excavation Cut, Fill and Truckloads Turn a dig into bank, loose, and compacted yards, and size the truckloads off the swollen volume, not the hole.

Decking (1)

Decking Deck Boards and Joist Spacing Turn a deck size into joists and deck-board rows, and settle 16 in vs 12 in joist spacing for wood or composite.

Tile (2)

Tile Tile, Thinset and Grout Turn an area and tile size into tiles, thinset bags, and grout, and pick the right trowel for the tile. Tile Tile Layout and Cuts Lay out a tile field: full tiles, the edge cuts, and whether to start at a wall or center it.

Masonry (2)

Masonry Concrete Block Wall (CMU) Turn a wall size into 8x8x16 blocks and mortar, and decide whether to build standard or reinforce with rebar and grout. Masonry Brick Veneer and Mortar Get the brick, mortar, and ties for a veneer wall, and compare brick sizes.

Solar (5)

Solar Solar System Size and Panel Count Turn your annual kWh usage and sun hours into a PV array size and panel count, and pick an offset target. Solar Inverter DC:AC Ratio Size a solar inverter to the array with the DC:AC loading ratio, and weigh clipping against cost by climate. Solar Solar String Sizing Find the modules-per-string range for an inverter using temperature-corrected module voltage. Solar Solar DC Wire and Voltage Drop Size a PV DC circuit conductor by NEC 690.8 ampacity and by voltage drop, and see which one governs. Solar Solar Battery Bank Sizing Size a battery bank in kWh and amp-hours from your daily load and days of autonomy.

Low Voltage (4)

Low Voltage Fiber vs Copper Cabling Choose copper, multimode, or single-mode cabling from the run length, the speed, and the environment. Low Voltage PoE Budget + Voltage Drop Find the PoE standard a device needs and whether the cable run delivers enough power. Low Voltage Rack Unit (RU) Planning Add up the rack units your gear needs and size the rack with room for airflow and growth. Low Voltage Cable Pull and Data Conduit Fill Estimate total cable for a set of drops and size the conduit that holds the bundle at 40% fill.

Hardscaping (1)

Hardscaping Paver Base and Bedding Turn a paved area into base gravel and bedding sand, and set the base depth by patio, driveway, or heavy use.

Irrigation (2)

Irrigation Irrigation Zone Sizing Find how many sprinkler heads fit on a zone and how many zones you need from your water supply. Irrigation Irrigation Pipe Sizing Size a supply main or zone lateral so the water stays under the safe velocity for your flow.

Estimating (4)

Estimating Waste Factor + Overage Advisor Get the right overage percent for a material and layout, and the amount to order. Estimating Trade Unit Converter Convert the length, area, volume, flow, pressure, power, and temperature units used in the trades. Estimating Material Cost Compare Compare two material or method options by their total installed cost and see which one really wins. Estimating Labor Hours Estimator Turn a quantity and a production rate into labor hours and crew days for planning.

Next up

Solar Inverter DC:AC ratio on the way

Low Voltage PoE budget + voltage drop on the way

Concrete Footing size (rule of thumb) on the way

Why a workbench and not a calculator

Most trade calculators hand you a number and stop. A real job needs a decision. Which wire, which pipe, order the ready-mix or bag it, and why. TradesWorkbench is built around that second question. Every tool shows the reasoning and the tradeoffs so you can stand behind the call and explain it to whoever asks. How it works.

These are planning tools. They do not replace a licensed professional, a permit, or an inspection, and they do not certify code compliance.