Free template · general contractors

A home addition estimate template written from the contractor's side of the job.

This is a free home addition estimate template with the whole build already itemized, permits through closeout: design and engineering, demolition and site prep at the tie-in, foundation, framing, roofing and exterior, windows and doors, mechanical rough-ins, insulation and drywall, interior finishes, and the labor and contingency lines at the end. Load it in the builder, delete what your addition doesn't need, and put your rates on what's left. The rates come blank on purpose: no template knows your market, and this one doesn't pretend to.

Search for a room addition estimate template and the results are mostly pages telling homeowners what other people's additions cost per square foot. That number is not an estimate; it's a mood. An actual addition is a small house attached to an occupied one, which is why this template carries a Temporary protection & dust barriers line, a Selective demolition at tie-in line, and three separate inspection lines: foundation, rough-in, final. Leave those lines out and the tie-in doesn't get any simpler. Only the estimate does.

10 sections · 61 line items·Rates blank on purpose·No sign-up

What’s in the template

Every section below loads into the builder exactly as listed. This is the actual checklist, not a preview of one. Delete what your job doesn’t need and price the rest.

Permits & preconstruction4 lines

Design and engineering, the building permit, mobilization, and the dust barriers that keep the rest of the house livable. Flat lines, quoted before anything gets loud.

  • Design & engineering
  • Building permit & fees
  • Mobilization
  • Temporary protection & dust barriers

Lump-sum items (permits, design, engineering) quoted flat.

Demolition & site prep6 lines

Selective demolition at the tie-in, clearing and grubbing, excavation and backfill by the cubic yard, gravel by the ton, and hauling off what came out.

  • Selective demolition at tie-in
  • Site clearing & grubbing
  • Excavation
  • Gravel base
  • Backfill & compaction
  • Demolition debris disposal

Excavation and fill quoted by cu yd; bulk gravel by weight.

Foundation5 lines

Footings and foundation walls by the linear foot, slab by the square foot, waterproofing, and the first of the three inspections.

  • Footing - form & pour
  • Foundation wall
  • Slab - pour & finish
  • Foundation waterproofing
  • Foundation inspection

Footings and foundation walls quoted by ln ft; slab by sq ft.

Framing7 lines

Floor, wall, and roof framing by the square foot, sheathing by the sheet, beams and headers per unit, house wrap, and framing labor by the day.

  • Floor framing & subfloor
  • Wall framing
  • Roof framing
  • Sheathing
  • Beams & headers
  • House wrap
  • Framing labor

Framed assemblies quoted by sq ft of area; sheathing by sheet.

Roofing & exterior7 lines

Underlayment and shingles by the square, flashing and drip edge, fascia, gutters, siding, and the exterior trim that ties the addition into the house it's attached to.

  • Roofing underlayment
  • Shingles - install
  • Flashing & drip edge
  • Fascia & soffit
  • Gutters & downspouts
  • Siding - install
  • Exterior trim

Roofing coverage by square (100 sq ft); trim and gutter runs by ln ft; siding by sq ft.

Windows & doors5 lines

Windows and doors per opening, plus the flashing, weatherstripping, and caulk that decide whether they leak.

  • Windows - install
  • Exterior door - install
  • Interior door - install
  • Window & door flashing
  • Weatherstripping & caulk

Mechanicals - rough-in7 lines

Electrical, plumbing, and HVAC rough-ins quoted flat, water and waste lines by the linear foot, equipment set per unit, and the rough-in inspection.

  • Rough-in electrical
  • Electrical panel & circuits
  • Rough-in plumbing
  • Water & waste lines
  • HVAC - ductwork
  • HVAC equipment - set
  • Rough-in inspection

System rough-ins quoted flat; water and waste lines by ln ft.

Insulation & drywall6 lines

Wall and ceiling insulation, vapor barrier, drywall hung by the sheet and finished by the square foot, and primer by the gallon.

  • Wall insulation
  • Ceiling insulation
  • Vapor barrier
  • Drywall - hang
  • Drywall - tape & finish
  • Prime walls & ceiling

Insulation, vapor barrier and drywall finish by sq ft; drywall boards by sheet; primer by gal.

Interior finishes8 lines

Flooring, baseboard and casing, paint, trim-out for electrical and plumbing, registers, cabinets, and countertop: the part the client actually looks at.

  • Flooring - install
  • Baseboard & casing
  • Interior paint
  • Electrical - trim out
  • Plumbing fixtures - set
  • HVAC registers & grilles
  • Cabinets - install
  • Countertop - install

Flooring and paint area by sq ft; trim and countertop runs by ln ft; paint by gal.

Labor, cleanup & closeout6 lines

General labor by the day, the dumpster, final cleanup, final inspection, and the general conditions and contingency lines that keep the job worth building.

  • General labor
  • Dumpster & disposal
  • Final cleanup
  • Final inspection
  • General conditions
  • Contingency allowance

Lump-sum items quoted flat; general labor by day. Overhead & profit is the percentage modifier.

How it works

01Load the template

Open it in the builder and the whole addition is already in place, permits through closeout: design and engineering, the tie-in demolition, footings, framing, roof, siding, rough-ins, drywall, finishes, and all three inspection lines. Start by deleting what your job doesn't need. A bump-out sheds sections quickly.

Permits → closeout
02Price it, margin in view

Put in your rates and what each line costs you: footings by the linear foot, slab and framing by the square foot, shingles by the square, labor by the day. The live P&L updates as you type, so you see what the job pays you while the number is still yours to change.

Live P&L
03Send the client version

Export a clean client estimate: prices, quantities, one total. The client copy is generated from a version that never held your costs, margin, or internal notes, so there's nothing to strip out and nothing to leak. It was never in there.

PDF · Excel · CSV · share link

Questions

The full guide (units, tax math, deposits, exports) lives on the Help page. It’s genuinely thorough. We’re as surprised as you.

For the longer answer, there’s a guide: How to Write a Construction Estimate.

What does a home addition estimate include?

Ten sections that follow the build in order: permits and preconstruction, demolition and site prep, foundation, framing, roofing and exterior, windows and doors, mechanical rough-ins, insulation and drywall, interior finishes, and labor, cleanup and closeout. Inside them are the lines that quietly disappear from addition quotes: backfill and compaction, house wrap, window and door flashing, the dumpster, and the rough-in inspection that has to pass before the drywall goes up. Delete what your addition doesn't need and rename what's left.

How do I price a home addition?

By its drivers, one line at a time. Excavation and backfill run by the cubic yard, gravel by the ton, footings and foundation walls by the linear foot, framed floor, wall, and roof areas by the square foot, roofing by the square, windows and doors per opening, rough-ins as flat scopes, and labor by the day. The math never changes underneath: rate, quantity, multiplier, whatever the unit label says. And the live P&L totals your side of it as you go, so you know the margin on the whole build before you sign up to pour its footings.

How do I handle the tie-in and other unknowns on an addition estimate?

As priced lines, not as apologies later. The template ships with a Selective demolition at tie-in line for the wall where new meets old, and a Contingency allowance under closeout for whatever that wall turns out to contain. General conditions gets its own flat line instead of hiding inside your rates. For the money mechanics, document modifiers cover an overhead and profit fee as a percentage of the subtotal, a discount, and an informational deposit line that shows the client what's due up front without changing the total.

Is the home addition estimate template free?

Yes. The whole builder runs without an account, and every export works on free: client PDF, Excel, CSV, plus the internal budget export, and share links pack a client-safe copy into the link. A free account adds one cloud-saved estimate. Pro is a one-time purchase, not a subscription: your name, logo, and contact line on client-facing exports, no Estimatery footer, unlimited cloud saves, and a Saved Items catalog for the lines you reuse. Construction software tends to bill monthly forever. This one asks once, and only if you want the logo.

Related templates

The checklist is done. The rates are your problem.
Opens the builder with this template loaded. No signup, no onboarding call.