Job takeoff
Window replacement takeoff
Rough opening, flashing membrane, casing and the heat-loss change for a window swap.
A takeoff is the trade word for the shopping list a job produces — every material, and how much of each, worked out by its own cited calculator.
- 4Measurements in
- 4Trades out
Give the job once
Every figure on the right follows these, in the units you choose.
Been given a quote for this job?
Paste it into the window replacement quote check: each line is read against these same calculators — what it leaves out, what it adds, and what to ask.
Check the quoteEvery trade, from those dimensions
then change a dimension, and each line shows what moved.
| Trade | Quantity | |
|---|---|---|
Fenestration Rough Opening CalculatorThe opening to order to, with shim space and an out-of-square allowance.How this figure was reached
Resting on
Change any other figure on the Fenestration Rough Opening Calculator | 48.99 in | |
Window Opening Flashing Membrane CalculatorMembrane for every opening — sill, jambs and head — measured at the rough opening rather than the window.
Why this quantity?
Resting on
The waste allowance: the calculator's working figure, a trade convention. Change any other figure on the Window Opening Flashing Membrane Calculator | 98.27 ft | |
Door & Window Casing CalculatorCasing around each opening, in stock lengths.
Why this quantity?
Resting on
The mitre waste: the calculator's working figure, a trade convention. Change any other figure on the Door & Window Casing Calculator | 70.4 linear ft | |
Window Heat Loss Savings CalculatorThe fabric saving across all of them — set the two U-factors on its own page.How this figure was reached
Resting on
Change any other figure on the Window Heat Loss Savings Calculator | 2240.18 BTU/hr reduction | |
Fenestration Rough Opening CalculatorThe opening to order to, with shim space and an out-of-square allowance.How this figure was reached | 1225 mm | |
Window Opening Flashing Membrane CalculatorMembrane for every opening — sill, jambs and head — measured at the rough opening rather than the window.
Why this quantity? | 29.48 m | |
Door & Window Casing CalculatorCasing around each opening, in stock lengths.
Why this quantity? | 21.12 m | |
Window Heat Loss Savings CalculatorThe fabric saving across all of them — set the two U-factors on its own page.How this figure was reached | 0.636 kW reduction |
Estimates, not a quote. Each row gives its base, the allowance on top, the adjusted figure and what to order; change an allowance on the row, or open its reasoning to see every figure it rests on. A trade's own page carries what it does not cover — open the one you are about to order against.
Labour and programme
Person-hours for the rows going in, from trade rules of thumb: a range for each piece of work, never a price.
- Window Opening Flashing Membrane16 h (4.0–32)
- Door & Window Casing3.9 h (2.1–8.6)
About 20 person-hours in all, between 6.1 and 41.
Trade by trade
- Glazier2 glaziers1 day
- Carpenter1 carpenterhalf a day
About 1½ days, one trade after another at eight hours a day. Left out: drying and curing, deliveries, inspections, trades overlapping.
2 rows carry no hours of their own
- Fenestration Rough Opening: a size or a check, not a piece of work
- Window Heat Loss Savings: a size or a check, not a piece of work
Labour and programme
Person-hours for the rows going in, from trade rules of thumb: a range for each piece of work, never a price.
- Window Opening Flashing Membrane16 h (4.0–32)
- Door & Window Casing3.8 h (2.1–8.4)
About 20 person-hours in all, between 6.1 and 40.
Trade by trade
- Glazier2 glaziers1 day
- Carpenter1 carpenterhalf a day
About 1½ days, one trade after another at eight hours a day. Left out: drying and curing, deliveries, inspections, trades overlapping.
2 rows carry no hours of their own
- Fenestration Rough Opening: a size or a check, not a piece of work
- Window Heat Loss Savings: a size or a check, not a piece of work
Setups you have saved
The build-up, the dimensions and any allowance you changed — kept on this device, and reusable on any job. Your prices are not copied in: they stay in your price book, so a setup never holds a stale one.
How far does a budget go?
At your own prices, with this build-up unchanged.
About this job
Replacing a window is a hole-in-the-wall job, and the hole is where the estimate lives. The rough opening is not the window's size: it is the window plus shim space at the jambs and head, plus whatever the sill pan and its build-up take, plus an allowance for an opening that is not square — which, in any building older than the people replacing its windows, it will not be.
The flashing membrane is the row that decides whether the wall behind the window is still dry in ten years. It runs the full perimeter with a defined lap past each corner, and it is installed in an order — sill first, then jambs over the sill, then head over the jambs — so that every lap sheds water outward. That sequence is not a preference. Reverse any part of it and the wall drains inward at that joint.
The savings row is the reason the job gets approved and the least reliable number on the page. It compares two U-factors over the glazed area at a design temperature difference, which is the physics; what it cannot see is the air leakage around the old frame, which is often the larger share of what you are actually fixing.
How each line reads
- Base
- What the calculator gives for these dimensions, before anything is added.
- Allowance
- Cutting waste, a lap or spare stock — named, with where it comes from, and changeable on the row.
- Adjusted
- The base with its allowance on top.
- Order
- What to buy: the adjusted figure in whole boards, bags, rolls or lengths.
The order this happens in
Quantities do not tell you the sequence, and on this job the sequence is where the money goes wrong.
- Measure the existing opening in three places each way — it will not be square.
- Order to the rough opening, not to the old window, and confirm the handing and the opening direction.
- Strip back far enough to see the sheathing and whatever the old flashing was doing.
- Flash the sill first, or fit the sill pan, with end dams and a back dam, sloping out and turned up the jambs.
- Set the window on it, shim at the fixing points only, and fix through the shims rather than beside them; leave the bottom flange untaped so the sill can drain.
- Flash the jambs over the ends of the sill piece, then the head over the jambs, each lapping over the one below, then insulate and seal the inside.
What this takeoff does not cover
- The window itself, its glazing specification and its hardware.
- Structural change. Making an opening larger is a lintel question and this takes off nothing structural.
- Interior finishes beyond the casing: reveals, window boards, plaster repair and paint.
- Repair to whatever the old window was hiding, which is the item most likely to change the price.
- The air leakage the old frame was responsible for, which the savings row does not include.
Quote check
Been given a quote for this job?
Paste it into the window replacement quote check. Every line of it is read against these same calculators and your measurements. Quantities only, never prices.
What it leaves out
Every line this takeoff has that nothing on the quote reads as.
What it adds
Labour, removal, hire, fees — each named for what it is.
What to ask
One list of questions, ready to copy. Never a verdict.
More takeoffs
Other job takeoffs
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Run this takeoff
Frequently asked questions
- What does the window replacement takeoff give for a typical job?
- Opened at Window width 1.2 m · Window height 1.2 m · Windows 4 · Rough opening over the window 0.03 m, it orders: Fenestration Rough Opening, 1,225 mm; Window Opening Flashing Membrane, 29.5 m; Door & Window Casing, 21.1 m; Window Heat Loss Savings, 0.64 kW reduction. Opened at Window width 4 ft · Window height 4 ft · Windows 4 · Rough opening over the window 1 in: Fenestration Rough Opening, 49 in; Window Opening Flashing Membrane, 98.3 ft; Door & Window Casing, 70.4 linear ft; Window Heat Loss Savings, 2,240 BTU/hr reduction. Every figure follows the dimensions you give it.
- Which calculators does the window replacement takeoff run?
- 4 calculators, one to a line: Fenestration Rough Opening Calculator, Window Opening Flashing Membrane Calculator, Door & Window Casing Calculator, Window Heat Loss Savings Calculator. Each has a page of its own with its formula and its sources; the takeoff runs them all on one set of dimensions.
- What does the window replacement takeoff leave out?
- 5 things, each named on this page: The window itself, its glazing specification and its hardware; Structural change; Interior finishes beyond the casing; Repair to whatever the old window was hiding, which is the item most likely to change the price; The air leakage the old frame was responsible for, which the savings row does not include.
- Can I check a quote for this job against the takeoff?
- Yes. The window replacement quote check reads a quote's lines against these same calculators and your measurements, and reports what it leaves out, what it adds and what to ask. It reads quantities, never prices.