Craft Quantities
Plan & Takeoffs

Quote check

Check an extension shell quote

Paste the quote you were given and enter your measurements. Every line is read against the job: what the quote leaves out, what it adds, which quantities sit outside the computed range, and what to ask. Quantities only — never prices.
  • 22Lines the job needs
  • 14Measurements
  • QuestionsNever a verdict

How the quote is read

Each line of an extension shell quote is matched to the line of the job it names, or marked as something the Extension shell, one or two storeys takeoff does not measure — labour, removal, hire, fees, or anything else. Work the takeoff lists as part of the job but gives no quantity for is read as that work, not as something the quote adds.

The job’s own figures come from 14 measurements — width along the house, projection from the house, wall height for each storey, cavity wall thickness, doors and windows in the new walls, opening width, each, opening height, each, footing width, from the design, footing concrete depth, from the design, trench depth, damp-proof course above the ground, dig over the floor, roof slope factor, eaves overhang — run through the same calculators as the takeoff, so the two give the same figure for the same job.

Reading an extension shell quote

An extension quote is written before anyone has seen what is under the lawn, and the groundwork is where two quotes for one drawing can part company. Worth asking what trench depth each price allows, what happens to the price if the inspector wants the trenches taken further down, and how the dug soil leaves the site; its weight, not its bulk, decides how many skips or grab loads it fills, so the number of loads each quote names is the figure to hold against the loads on this check.

The lines on this check stop where the building keeps the weather out, and a shell quote can stop somewhere else. Worth settling whether the price carries the doors and windows themselves, the roof tiles as well as the battens, the gutters with their downpipes and the drain they run to, and knocking through into the house with its steel, padstones and props; and whether the engineer's calculations, the building control fees and any party wall surveyor sit inside the figure or beside it.

Three steps

  1. Give your measurements. The page opens on a typical job so it has something to show.
  2. Paste the quote's lines as they came, or add them one at a time. Leave the prices in — they are taken out, never read.
  3. Read the report: what is left out, what is added, what sits outside the range, and one list of questions to send.

Your quote

The extension shell quote you were given

Paste from an email, or open or drop a PDF, Excel, CSV or text file, or a photo of the quote. Amounts of money are taken out before anything is read — this page compares quantities, never prices.

Nothing you paste or open leaves this device.

or one the job needs:

The reading

What the quote says, against the job

Extension shell · Width along the house 16.5 ft · Projection from the house 13 ft · Wall height for each storey 8 ft · Cavity wall thickness 11.8 in · Doors and windows in the new walls 3 · Opening width, each 5 ft · Opening height, each 7 ft · Footing width, from the design 2 ft · Footing concrete depth, from the design 2.5 ft · Trench depth 3.5 ft · Damp-proof course above the ground 6 in · Dig over the floor 11.8 in · Roof slope factor 1.06 · Eaves overhang 11.8 inWidth along the house 5 m · Projection from the house 4 m · Wall height for each storey 2.5 m · Cavity wall thickness 0.3 m · Doors and windows in the new walls 3 · Opening width, each 1.5 m · Opening height, each 2.1 m · Footing width, from the design 0.6 m · Footing concrete depth, from the design 0.75 m · Trench depth 1 m · Damp-proof course above the ground 0.15 m · Dig over the floor 0.3 m · Roof slope factor 1.06 · Eaves overhang 0.3 m

  • What it leaves out

    Every line the job needs that nothing on the quote reads as, with the quantity your measurements produce.

  • What it adds

    Lines this job's takeoff does not measure — labour, removal, hire, fees, anything else — each named for what it is.

  • What sits outside the range

    Quantities above or below the computed range, by how much, in the quote's unit or converted and shown.

  • What to ask

    One list of questions, in the quote's order, ready to copy and send. Questions, never a verdict.

Paste the quote above, or add its lines one at a time. The reading appears here as each line is read.

Outside what this takeoff measures

8

Nothing in the reading measures these. Whether the quote covers each is worth asking in its own right: a scope missing from a quote tends to become a cost after work has started. Why each is left out is on the takeoff.

  • Every structural size
  • A flat roof over a single storey
  • The tiles or slates, and their fixings
  • The masonry above the eaves
  • The precast beams and infill blocks of a beam-and-block floor, laid to the floor supplier's layout, which sizes them; no operation lists them yet
  • Planning permission, a party wall notice or agreement where the extension stands on or near a boundary, and a build-over agreement for, or a diversion of, a public sewer under the footprint
  • Movement joints in the new brickwork, and the detail where a return meets the house, which the designer chooses between a tie system, a toothed bond and a joint
  • Everything after weathertight

The reference

Every line the reading looks for

For Width along the house 16.5 ft · Projection from the house 13 ft · Wall height for each storey 8 ft · Cavity wall thickness 11.8 in · Doors and windows in the new walls 3 · Opening width, each 5 ft · Opening height, each 7 ft · Footing width, from the design 2 ft · Footing concrete depth, from the design 2.5 ft · Trench depth 3.5 ft · Damp-proof course above the ground 6 in · Dig over the floor 11.8 in · Roof slope factor 1.06 · Eaves overhang 11.8 inWidth along the house 5 m · Projection from the house 4 m · Wall height for each storey 2.5 m · Cavity wall thickness 0.3 m · Doors and windows in the new walls 3 · Opening width, each 1.5 m · Opening height, each 2.1 m · Footing width, from the design 0.6 m · Footing concrete depth, from the design 0.75 m · Trench depth 1 m · Damp-proof course above the ground 0.15 m · Dig over the floor 0.3 m · Roof slope factor 1.06 · Eaves overhang 0.3 m. Each is the calculator linked under it, run with those measurements; a range is that calculator at both ends of one choice, not a margin for error.

How the ranges are taken

Where the choice is cutting waste, the ends are the site’s own allowances: 5%, the tight buffer of a crew with a planned set-out, and 15%, the wider one a first-timer orders. Where the calculator decides between patterns or materials, the ends are the options it offers. Where it adds nothing for loss, the range runs from the net quantity to 15% over it.

A minimum — the fewest hangers a spacing allows, the least airflow a room needs — has no upper end. A single figure carries an allowance the material itself needs, such as a lap, and names it.

What a reading like this cannot see

  • It does not know your prices, your market, or what the work ought to cost.
  • It does not know the building — the access, the condition of what is there, or what has to happen first.
  • It cannot check a lump sum, because there is no quantity in one.
  • A line it reads as missing may be priced under another name. A quantity outside the range is not evidence of anything. Each is a reason to ask a question.
  • Two quotes are not comparable until their scopes are.
  • It is not advice, and it is no substitute for a second quote.

The full takeoff

Every quantity for this job, with its working

The Extension shell, one or two storeys takeoff runs the same calculators on the same measurements and shows what sits under each line here.

Open the takeoffEvery quote check

  • Base, allowance, order

    Each line's quantity before and after its allowance, and what to buy.

  • Every allowance editable

    Change a waste figure and the order follows, with its source named.

  • Into a project

    Add the whole job to a workspace with your own prices.

Frequently asked questions

What quantities does an extension shell job need?
It depends on the measurements, so this page asks for yours. At the size it opens on — Width along the house 5 m · Projection from the house 4 m · Wall height for each storey 2.5 m · Cavity wall thickness 0.3 m · Doors and windows in the new walls 3 · Opening width, each 1.5 m · Opening height, each 2.1 m · Footing width, from the design 0.6 m · Footing concrete depth, from the design 0.75 m · Trench depth 1 m · Damp-proof course above the ground 0.15 m · Dig over the floor 0.3 m · Roof slope factor 1.06 · Eaves overhang 0.3 m — the lines come to: Footing trenches, dug, 9.75 m³ (loose); Dig over the floor, 6.11 m³ (loose); Footing concrete, 6.14–6.73 m³; Blocks below the damp-proof course, both leaves, 108–119 blocks; Hardcore under the slab, 5.37–6.18 metric tons; Floor insulation boards, 6–7 sheets (2400x1200 mm); Floor slab concrete, 1.71–1.87 m³; Inner leaf blocks, clear of the openings, 221–242 blocks; Inner leaf blocks, above and below the openings, 19–21 blocks; Facing bricks, clear of the openings, 1,323–1,449 bricks; Facing bricks, above and below the openings, 112–123 bricks; Wall ties across the cavity, 93 ties; Cavity boards, 9–10 sheets (2400x1200 mm); Weep holes at the damp course, 23 weep holes; Lean-to rafters, 10 trusses; Fascia along the eaves, 2 x 3.6 m boards; Underlay over the lean-to, 1 roll; Flashing where the roof meets the house, 4–5 sheets; Gutter along the eaves, 2–3 x 4 m sections; Gutter brackets, 10 hangers; Flashing tape round the openings, 28.4–31.1 m; Skip (dumpster) loads for the spoil, 15.9 m³. In imperial units — Width along the house 16.5 ft · Projection from the house 13 ft · Wall height for each storey 8 ft · Cavity wall thickness 11.8 in · Doors and windows in the new walls 3 · Opening width, each 5 ft · Opening height, each 7 ft · Footing width, from the design 2 ft · Footing concrete depth, from the design 2.5 ft · Trench depth 3.5 ft · Damp-proof course above the ground 6 in · Dig over the floor 11.8 in · Roof slope factor 1.06 · Eaves overhang 11.8 in — they come to: Footing trenches, dug, 13.8 yd³; Dig over the floor, 7.92 yd³; Footing concrete, 8.26–9.05 yd³; Blocks below the damp-proof course, both leaves, 151–165 blocks; Hardcore under the slab, 6–6.9 tons; Floor insulation boards, 6–7 sheets (4x8 ft); Floor slab concrete, 2.27–2.48 cubic yards; Inner leaf blocks, clear of the openings, 260–285 blocks; Inner leaf blocks, above and below the openings, 18–20 blocks; Facing bricks, clear of the openings, 1,584–1,735 bricks; Facing bricks, above and below the openings, 108–119 bricks; Wall ties across the cavity, 89 ties; Cavity boards, 8–9 sheets (4x8 ft); Weep holes at the damp course, 23 weep holes; Lean-to rafters, 10 trusses; Fascia along the eaves, 2 x 12 ft boards; Underlay over the lean-to, 1 roll; Flashing where the roof meets the house, 2–3 sheets; Gutter along the eaves, 2–3 x 10 ft sections; Gutter brackets, 10 hangers; Flashing tape round the openings, 94.5–103 ft; Skip (dumpster) loads for the spoil, 21.7 yd³.
Which line on an extension shell quote varies the most?
The Gutter along the eaves: 2–3 x 4 m sections for a job measured Width along the house 5 m · Projection from the house 4 m · Wall height for each storey 2.5 m · Cavity wall thickness 0.3 m · Doors and windows in the new walls 3 · Opening width, each 1.5 m · Opening height, each 2.1 m · Footing width, from the design 0.6 m · Footing concrete depth, from the design 0.75 m · Trench depth 1 m · Damp-proof course above the ground 0.15 m · Dig over the floor 0.3 m · Roof slope factor 1.06 · Eaves overhang 0.3 m, depending on how much is allowed for loss over the net figure, up to 15%.
What does an extension shell quote often leave out?
The reading names every line of the job that nothing on the quote reads as — any of the 22 lines the takeoff measures. The takeoff also lists 8 things it does not measure, shown under the reading, and each is worth asking about: a scope missing from a quote tends to become a cost after work has started.
Can I paste the quote exactly as it came?
Yes — from an email, a PDF or a spreadsheet, one item to a line. Amounts of money are taken out before anything is read, headings and totals are skipped, and each line is shown with what it was read as, so a misreading is one correction. Quantities in the other unit system are converted and the conversion is shown; a count of boxes is never compared with a count of tiles.
Does this check the price as well?
No. It reads quantities, never prices, and this site publishes none: an installed price moves with the market, the season, the access and the specification, so a figure for what the work ought to cost would give you confidence in a number nobody can defend. A quantity against your own measurements is checkable, and every figure here links to the calculator that produced it.