Roof Project
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Task directory

Roof and gutter calculators

Choose the task that matches your measurement, material decision or quote. Every calculator keeps its own inputs and limits visible.

63 tasks listed. Browse the directory below or enable JavaScript to search.

Roof measurement

Roof measurement

Start with the measurements you have: rise and run, a roof footprint or measured surface areas. Choose the matching tool before estimating materials.

Pitch and rafters

Roof pitch and slopeTurn rise, run or an angle into a roof pitch and slope measures. Rafter lengthFind the sloped length of a simple roof section from rise and run. Hip rafter lengthFind a hip centerline from two plan offsets and vertical rise.

Area and roof shapes

Roof area from footprint and pitchEstimate sloped area when the footprint and pitch are known. Measured quantity totalsAdd separate measured areas, lengths or fitting counts in one unit. Roof squaresConvert measured roof area into 100-square-foot roofing units. Gable roof areaEstimate both sloped sides of an equal-gable roof section. Hip roof areaAdd four measured sloped planes for a hip roof. Lean-to roof areaFind the sloped area of one single-slope roof plane. Gambrel roof areaAdd the measured upper and lower planes on both sides.

Rain collection

Roof runoff volumeEstimate gallons from catchment area, rainfall and runoff coefficient. Rain barrel yieldEstimate potential rainwater volume reaching a collection point.

Attic ventilation

Attic ventilationTranslate attic area and vent assumptions into NFVA targets and ridge rolls.

Roof materials

Roof materials

Turn measured roof area and lengths into purchase quantities. Use the coverage, stock dimensions and overlap requirements for the product you plan to buy.

Covering and purchase quantities

Asphalt shingle bundlesEstimate bundles from roof area and the product coverage on the package. Metal roofing panelsEstimate panels from area and exposed panel coverage after overlap. Area coverage quantityConvert area, coverage and waste into rounded purchase units. Sheathing wasteAdd a selected waste allowance to a measured roof area.

Underlayment and barriers

Underlayment rollsEstimate rolls from roof area, roll coverage and waste. Ice and water barrierEstimate barrier rolls for a measured protected strip.

Edges, caps and flashing

Starter strip bundlesRound a measured starter-strip length up to product coverage. Ridge cap quantityEstimate ridge or hip cap bundles from covered length. Drip edge quantityAdd eave and rake lengths and round up to stock coverage. Valley flashing quantityAdd valley runs and round up to selected piece length.

Nails, vent pieces and battens

Roofing nail quantityMultiply bundle, shingle and nailing inputs, then size nail boxes. Ridge vent lengthRound a measured ridge length up to stock vent pieces. Roof batten quantityEstimate battens from gauge, plane length, waste and stock length.

Membrane and cutting

Flat roof membrane layoutEstimate repeated membrane strips and side-seam footage. Hip and valley sheet cutsPlan hip and valley cuts from a measured drawing and product dimensions. Planning guide

Roof costs

Roof costs

Compare the arithmetic behind a roof quote. Match your measured quantity to the quoted unit, then check which work the supplied price includes.

Material subtotals

Quoted unit-rate subtotalMultiply a measured quantity by a rate from a quote or product price. Metal roof material costMultiply panel count by the price per panel.

Installation and replacement

Roof replacement rangeApply low and high quoted rates to a measured quantity. Asphalt shingle installation costApply a quoted installation range to measured roofing quantity.

Tear-off and repair

Roof tear-off costMultiply measured roof area by a quoted tear-off rate. Roof repair costMultiply repair length or quantity by a quoted unit rate.

Annual cost comparison

Repair versus replacement annual costCompare annualized repair and replacement assumptions.

Gutters and downspouts

Gutters and downspouts

Plan the actual gutter runs and downspout routes around your house. Move from measured footage to quantities, drainage comparisons and clearly scoped costs.

Measurement and routes

Gutter lengthAdd measured gutter runs around the house. Gutter sectionsRound a measured run up to stock section length. Gutter slope dropConvert a run and slope into the fall across the gutter. Downspout count by spacingRound gutter length up to a maximum served length. Downspout lengthAdd vertical and horizontal route segments and stock pieces. Gutter service lengthEstimate served lengths from a selected maximum per route. Downspout extensionAdd route segments and round up to stock extension pieces.

Supports and fittings

Gutter hangersEstimate hanger count from run length and spacing. Gutter hanger spacingEstimate supports using a tighter selected spacing. Gutter end capsCount two end caps for each open-ended run. Gutter outletsMatch planned downspouts to outlet count. Downspout elbowsMultiply route groups by fittings per route. Gutter cornersAdd inside and outside corners from the measured perimeter. Gutter parts takeoffEstimate sections, spacing-only hangers, downspouts and outlets. Splash block quantityMatch selected surface-discharge outlets to splash blocks.

Size, capacity and collection

Gutter size selectorCompare listed half-round sizes against a rainfall and capacity condition. Gutter capacityCompare runoff demand with a candidate gutter capacity. Downspout capacity countEstimate how many downspouts a runoff rate requires. Maximum roof area for gutter capacityConvert candidate capacity and rainfall intensity into plan area. Gutter to barrel yieldEstimate rainwater volume available to a collection point. Roof runoff rateConvert plan area and rainfall intensity into cubic feet per second and gallons per minute.

Costs and maintenance

Gutter material costAdd gutter, hanger and downspout component subtotals. Gutter installation costEstimate an installed range from length and a stated rate basis. Gutter replacement costApply installation and removal rates to measured length. Gutter removal costMultiply gutter length by one quoted removal rate. Gutter repair costOrganize a repair quote by damaged scope and billing unit. Planning guide Gutter cleaning costApply a source-dated cleaning range to gutter length. Gutter guard costCombine material cost with labor estimated from productivity.

Each task keeps its own inputs and explanation. Start with the measurement you have, then check the units and estimate limits before combining results.