Residential · R05

House Extension / Addition Cost Estimate — 25 m²

25 m² 36 work items 6 sections Toronto, Canada

About This Project

Cost estimate for a 30 m² ground-floor house extension. Covers foundation underpinning or new strip footing, structural opening in existing wall (RSJ/steel beam), masonry or timber frame walls, flat or pitched roof, matching exterior finishes, MEP extension, interior finishing, and building control compliance.

Scope of Works

Demolition & Preparation (5)Foundations & Structure (8)Roof (Flat) (7)Openings & External Finishes (4)Internal Finishes (6)MEP (6)

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Full Professional Estimate
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Overview

iKey project metrics at a glance — total cost per m², labor and material shares, and estimated duration
Source: Text Query
C$853.89
Cost / m²
22.5%
Labor
55.7%
Materials
96 days
Est. Duration

Work Items

16 items iAdjust quantities or remove items, then recalculate. Click item name to jump to details.

Project Context

iInput parameters, location adjustment factors, and detection confidence for this estimate
Source
Residential
25 m² · 16 items
SourceText Query
Work Items16 items · 16 Categories
CurrencyC$ CAD
LanguageEnglish
Date05 Apr 2026
House Extension / Addition 25 m² Toronto Canada
Cost / m²
C$853.89
25 m²
Est. Duration
3 months
96 days
Overhead
15%
C$2,531.30
Direct Costs
79%
C$16,875.39
Location
Toronto, Canada
Americas
×1.07
Estimate Overview
C$21,347.35
C$853.89 / m² · 3 months (96 days)
Labor 22% Materials 56% Equipment 1% Overhead 12% Profit 9%
Contingency (P80)
+8%
C$1,793.18
Budget (P80)
C$23,140.53
recommended
Resources
54
34 mat · 5 lab · 15 equ
Overhead + Profit
12% + 9%
C$4,471.96
Pricing Methodology
Data Source: DDC Pricing DB — English · 55,719 items · CWICR
City Adjustment
🏛 Toronto, Canada
Your city matches the base — coefficients ×1.00
PPP Coefficients
Labor Factor
×
click to adjust
Material Factor
×
click to adjust
Equipment Factor
×
click to adjust
Prices from a professional construction database (55,719 items), adjusted to your city using construction-specific Purchasing Power Parity (PPP). Coefficients can be manually adjusted.
Detection Confidence
50%

Cost Breakdown

iHow the total cost is distributed: labor, materials, equipment, overhead, and profit margins
C$16,875.39Direct Cost
Labor (22%)C$4,809.77
Materials (56%)C$11,886.74
Equipment (1%)C$178.88
Overhead (12%)C$2,531.30
Profit (9%)C$1,940.66
Cost / m²
LaborC$192.39
MaterialsC$475.47
EquipmentC$7.16
OverheadC$101.25
ProfitC$77.63
Grand TotalC$853.89
Materials / Labor
2.47
Direct Cost %
79.1%
16 work items across 16 categories, 54 resources

Cost Flow

16iVisual flow of the total budget through work categories, showing proportional cost distribution
Total CostC$21,347.35Doors: C$459.33 (2.2%)Heating: C$523.28 (2.5%)Roofing: C$534.43 (2.5%)Windows: C$1,224.21 (5.7%)Bathroom: C$52.25 (0.2%)Flooring: C$542.69 (2.5%)Painting: C$199.09 (0.9%)Plumbing: C$926.24 (4.3%)Earthwork: C$44.03 (0.2%)Structure: C$1,113.03 (5.2%)Electrical: C$401.79 (1.9%)Foundation: C$579.45 (2.7%)Insulation: C$1,832.32 (8.6%)Plastering: C$2,035.89 (9.5%)External Walls: C$3,801.28 (17.8%)Internal Walls: C$7,078.03 (33.2%)Doors2.2%Heating2.5%Roofing2.5%Windows5.7%Bathroom0.2%Flooring2.5%Painting0.9%Plumbing4.3%Earthwork0.2%Structure5.2%Electrical1.9%Foundation2.7%Insulation8.6%Plastering9.5%External Walls17.8%Internal Walls33.2%

Categories

16iCost distribution by work category — earthwork, structure, facade, MEP, finishes, etc.
CategoryCostCost / m²Share
DoorsC$459.33C$18.372.2%
HeatingC$523.28C$20.932.5%
RoofingC$534.43C$21.382.5%
WindowsC$1,224.21C$48.975.7%
BathroomC$52.25C$2.090.2%
FlooringC$542.69C$21.712.5%
PaintingC$199.09C$7.960.9%
PlumbingC$926.24C$37.054.3%
EarthworkC$44.03C$1.760.2%
StructureC$1,113.03C$44.525.2%
ElectricalC$401.79C$16.071.9%
FoundationC$579.45C$23.182.7%
InsulationC$1,832.32C$73.298.6%
PlasteringC$2,035.89C$81.449.5%
External WallsC$3,801.28C$152.0517.8%
Internal WallsC$7,078.03C$283.1233.2%

Top Items

DescriptionTotal
Limestone partition wall masonry: unreinforced with a f…C$7,078.03
Masonry of external and internal brick walls with an ai…C$3,801.28
Continuous leveling of interior surfaces (single-layer …C$2,035.89
Insulation of interior walls on wood with spray guns us…C$1,832.32
Installation of PVC profile window blocks in residentia…C$1,224.21

What-If Scenarios

iExplore how changes in material, labor, or equipment costs affect the total project budget
Optimistic (-10%)
C$19,212.61
↓ C$2,134.74 savings
Labor -10% · Materials -10% · Equipment -10%
Base Estimate
C$21,347.35
Deterministic
Labor ×1.00 · Materials ×1.00 · Equipment ×1.00
Pessimistic (+15%)
C$24,549.45
↑ C$3,202.10 increase
Labor +15% · Materials +15% · Equipment +15%
Custom Scenario: Adjust cost components
Labor 0%
Materials 0%
Equipment 0%
Custom Scenario Total Cost
C$21,347.35

Project Schedule

≈3 monthsiProject timeline with critical path method (CPM), Gantt chart, and resource allocation
Construction PhasesAI
Site PreparationSite clearing, temporary facilities setup, access roads8d
EarthworksExcavation, grading, soil compaction, utility trenches8d
FoundationFoundation excavation, formwork, concrete pouring and curing8d
Structural FrameworkFraming, structural elements, load-bearing walls8d
RoofingRoof framing, sheathing, weatherproofing, finish roofing8d
External WallsExterior wall construction, sheathing, weather barrier8d
Windows and Exterior DoorsInstallation of windows and exterior door frames8d
MEP Rough-inElectrical wiring, plumbing, HVAC rough installation8d
InsulationWall and ceiling insulation installation8d
Drywall and PlasteringDrywall installation, taping, mudding, plastering8d
Interior DoorsInterior door frame and door installation8d
FlooringSubfloor preparation, finish flooring installation8d
Bathroom FixturesBathroom fixture installation, tiling, waterproofing8d
MEP FinishFinal electrical, plumbing, and HVAC connections8d
Painting and FinishesInterior and exterior painting, final trim work8d
Final Cleanup and HandoverFinal cleaning, inspections, punch list completion8d
3
months
96
days
16
phases
12
Critical Path
6
Peak workers
157
Labor Hours
M1 M2 M3 M4 Crew/Float Site Preparation Site Preparation: 8d, Crew 2, Float 0d 8d 2 / - Earthworks Earthworks: 8d, Crew 2, Float 0d 8d 2 / - Foundation Foundation: 8d, Crew 2, Float 0d 8d 2 / - Structural Framework Structural Framework: 8d, Crew 2, Float 0d 8d 2 / - Roofing Roofing: 8d, Crew 2, Float 0d 8d 2 / - External Walls External Walls: 8d, Crew 2, Float 48d 8d 2 / 48d Windows and Exterior … Windows and Exterior Doors: 8d, Crew 2, Float 48d 8d 2 / 48d MEP Rough-in MEP Rough-in: 8d, Crew 2, Float 4d 8d 2 / 4d Insulation Insulation: 8d, Crew 2, Float 0d 8d 2 / - Drywall and Plastering Drywall and Plastering: 8d, Crew 2, Float 0d 8d 2 / - Interior Doors Interior Doors: 8d, Crew 2, Float 32d 8d 2 / 32d Flooring Flooring: 8d, Crew 2, Float 0d 8d 2 / - Bathroom Fixtures Bathroom Fixtures: 8d, Crew 2, Float 0d 8d 2 / - MEP Finish MEP Finish: 8d, Crew 2, Float 0d 8d 2 / - Painting and Finishes Painting and Finishes: 8d, Crew 2, Float 0d 8d 2 / - Final Cleanup and Han… Final Cleanup and Handover: 8d, Crew 2, Float 0d 8d 2 / - Workers 21K 50% (28d)
Site PreparationEarthworksFoundationStructural FrameworkRoofingExternal WallsWindows and Exterior DoorsMEP Rough-inInsulationDrywall and PlasteringInterior DoorsFlooringBathroom FixturesMEP FinishPainting and FinishesFinal Cleanup and HandoverCumulative Cost
Labor Hours by Phase
External Walls
50 hours
MEP Finish
50 hours
Final Cleanup and Ha
50 hours
MEP Rough-in
47 hours
Structural Framework
42 hours
Site Preparation
17 hours
Drywall and Plasteri
15 hours
Roofing
10 hours
Flooring
6 hours
Painting and Finishe
5 hours
Windows and Exterior
5 hours
Foundation
5 hours
Insulation
2 hours
Interior Doors
2 hours
Bathroom Fixtures
2 hours
Earthworks
0 hours

Monthly Cash Flow

3 monthsiMonthly cost distribution and cumulative S-curve showing how project spending builds over time
56%
M1
96%
M2
100%
M3
MonthdaysMonthly Cost%Cumulative%
M11–30C$11,850.0755.5%C$11,850.0756%
M231–60C$8,744.9241.0%C$20,594.9996%
M361–90C$752.353.5%C$21,347.34100%

Daily Cash Flow

13 weeks
4%
D1
33%
D9
34%
D17
39%
D25
65%
D33
72%
D41
86%
D49
95%
D57
99%
D65
99%
D73
99%
D81
100%
D88
WeekdaysWeekly Cost%Cumulative%
W1D1–D7C$6,193.2829.0%C$6,193.2829%
W2D8–D14C$917.784.3%C$7,111.0533%
W3D15–D21C$373.161.7%C$7,484.2235%
W4D22–D28C$2,674.4512.5%C$10,158.6648%
W5D29–D35C$4,277.4620.0%C$14,436.1368%
W6D36–D42C$1,329.566.2%C$15,765.6974%
W7D43–D49C$2,546.8811.9%C$18,312.5886%
W8D50–D56C$1,781.408.3%C$20,093.9894%
W9D57–D63C$876.774.1%C$20,970.7598%
W10D64–D70C$164.440.8%C$21,135.1999%
W11D71–D77C$13.060.1%C$21,148.2599%
W12D78–D84C$99.550.5%C$21,247.79100%
W13D85–D88C$99.550.5%C$21,347.34100%

Line Items

16 itemsiDetailed work items grouped by category with quantities, unit prices, and resource breakdown
Earthwork 1 items C$44.03
#CodeDescriptionQtyUnitUnit PriceTotal
1KAME_KAME_KAKAME_KATOCON
Soil excavation using single-bucket electric dragline excavators with a bucket capacity of: 15 m3, soil group 3
3.0
25 m² × 0.12 = 3 m3(Earthwork)
m3C$11.60C$44.03
C$34.81 +15% C$5.22 +10% C$4.00
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 10.01hrsC$41.68C$0.28
Bulldozers, power 79 kW (108 hp)0.01Machine hoursC$50.27C$0.35
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$30.39C$0.21
Single-bucket electric walking excavators with dragline working equipment, bucket capacity 15 m30.01Machine hoursC$4,704.39C$33.17
Personnel: 3 man-hours/machine-hours0.01Machine hoursC$113.86C$0.80
Foundation 1 items C$579.45
#CodeDescriptionQtyUnitUnit PriceTotal
2KANE_KAME_KAKAME_RIKAConstruction of strip foundations: concrete1.5
25 m² × 0.06 = 1.5 m3(Foundation)
m3C$305.38C$579.45
C$458.06 +15% C$68.71 +10% C$52.68
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 14.23hrsC$22.99C$97.25
Water0.00m3C$121.04C$0.62
Electricity0.03kWhC$19.82C$0.62
Polyethylene film, thickness KA.MESA mm1.32m2C$40.69C$54.03
Construction nails0.00tC$245,571.78C$73.90
Quicklime, grade I0.00tC$23,480.15C$6.83
Hot-rolled wire in coils, diameter NE.TO-NE.SA mm0.00tC$169,761.86C$76.38
Edged softwood boards, natural moisture content, length RI-NE.SA m, width 100-250 mm, thickness 44-50 mm, grade III0.00m3C$38,813.26C$127.93
Tower cranes, lifting capacity 8 t0.32Machine hoursC$42.01C$13.42
Personnel: 1 person-hour/machine-hour0.32Machine hoursC$18.23C$5.82
Mobile cranes, lifting capacity 16 t0.01Machine hoursC$66.92C$0.36
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$18.23C$0.10
Universal front-end pneumatic wheeled single-bucket loaders, nominal capacity of main bucket RI.NE m3, load capacity 5 t0.00Machine hoursC$69.44C$0.26
Personnel: 1 person-hour/machine-hour0.00Machine hoursC$15.60C$0.06
Deep vibrators0.21Machine hoursC$0.56C$0.11
Flatbed trucks, load capacity up to 5 tons0.01Machine hoursC$25.99C$0.24
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$13.56C$0.12
Structure 1 items C$1,113.03
#CodeDescriptionQtyUnitUnit PriceTotal
3KANE_MEDX_KAKAPU_KAME
Construction of reinforced concrete floors and slabs up to 200 mm thick in permanent formwork (concrete supplied in buck
1.2
25 m² × 0.05 = 1.25 m3(Structure)
m3C$703.90C$1,113.03
C$879.88 +15% C$131.98 +10% C$101.18
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 110.42hrsC$23.00C$250.06
Anthracene oil0.00tC$33,376.43C$75.09
Water0.00m3C$54.41C$0.28
Electricity0.05kWhC$8.91C$0.56
Polyethylene film, thickness KA.MESA mm0.54m2C$18.29C$9.77
Construction nails0.00tC$110,381.79C$13.68
Light wire, diameter ME.ME mm0.00tC$112,428.54C$28.19
Edged coniferous timber (spruce, pine), natural moisture content, length RI-NE.SA m, width 20-90 mm, thickness 20-90 mm, grade III0.02m3C$21,098.29C$327.15
Edged softwood board, natural moisture content, length RI-NE.SA m, width 100-250 mm, thickness 25 mm, grade III0.00m3C$17,446.13C$34.89
Edged softwood boards, natural moisture content, length RI-NE.SA m, width 100-250 mm, thickness 44-50 mm, grade III0.01m3C$17,446.13C$113.33
Tower cranes, lifting capacity 8 t0.34Machine hoursC$42.55C$14.36
Personnel: 1 person-hour/machine-hour0.34Machine hoursC$19.02C$6.42
Mobile cranes, lifting capacity 16 t0.02Machine hoursC$67.79C$1.23
Personnel: 1 person-hour/machine-hour0.02Machine hoursC$19.02C$0.34
Universal front-end pneumatic wheeled single-bucket loaders, nominal capacity of main bucket RI.NE m3, load capacity 5 t0.03Machine hoursC$70.34C$2.34
Personnel: 1 person-hour/machine-hour0.03Machine hoursC$16.28C$0.54
Deep vibrators0.50Machine hoursC$0.56C$0.29
Trucks, load capacity up to 8 tons0.03Machine hoursC$37.21C$1.01
Personnel: 1 person-hour/machine-hour0.03Machine hoursC$14.16C$0.38
External Walls 1 items C$3,801.28
#CodeDescriptionQtyUnitUnit PriceTotal
4KAVO_KARI_KAMESA_KAMECON
Masonry of external and internal brick walls with an air gap: with a floor height of up to 4 m
5.2
25 m² × 0.21 = 5.25 m3(External Walls)
m3C$572.37C$3,801.28
C$3,004.97 +15% C$450.74 +10% C$345.57
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 129.77hrsC$52.98C$1,577.12
Water1.31m3C$1,000.25C$1,313.75
Tower cranes, lifting capacity 8 t1.73Machine hoursC$24.90C$43.14
Personnel: 1 person-hour/machine-hour1.73Machine hoursC$40.96C$70.96
Internal Walls 1 items C$7,078.03
#CodeDescriptionQtyUnitUnit PriceTotal
5KAVO_KATO_KAKATO_KALI
Limestone partition wall masonry: unreinforced with a floor height of up to 4 m
1.8
25 m² × 0.07 = 1.75 m3(Internal Walls)
m3C$3,197.30C$7,078.03
C$5,595.29 +15% C$839.29 +10% C$643.46
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 116.19hrsC$23.08C$373.61
Water0.17m3C$98.59C$17.20
Masonry mortar, cement-lime, M250.10m3C$11,043.17C$1,159.31
Edged coniferous timber (spruce, pine), natural moisture content, length RI-NE.SA m, width 20-90 mm, thickness 20-90 mm, grade III0.10m3C$38,231.28C$4,014.08
Tower cranes, lifting capacity 8 t0.51Machine hoursC$42.27C$21.45
Personnel: 1 person-hour/machine-hour0.51Machine hoursC$19.00C$9.64
Roofing 1 items C$534.43
#CodeDescriptionQtyUnitUnit PriceTotal
6MERI_KAME_KAKALI_KASA
Installation of tile roofs: grooved stamped or pressed (ceramic and cement-sand (concrete))
10.0
25 m² × 0.4 = 10 m2(Roofing)
m2C$42.25C$534.43
C$422.47 +15% C$63.37 +10% C$48.58
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 19.66hrsC$26.94C$260.21
Steel roofing nails, diameter 2-3 mm, length 20-40 mm0.78kgC$20.40C$15.92
Galvanized steel washers, round, hole diameter M16-240.36kgC$49.58C$17.71
Ready-mixed masonry mortar, cement, M1000.03m3C$1,108.91C$29.96
Galvanized sheet steel, thickness KA.LI mm0.01tC$16,813.26C$84.05
Tower cranes, lifting capacity 8 t0.14Machine hoursC$44.81C$6.10
Personnel: 1 person-hour/machine-hour0.14Machine hoursC$20.34C$2.77
Mobile cranes, lifting capacity 16 t0.04Machine hoursC$71.38C$2.57
Personnel: 1 person-hour/machine-hour0.04Machine hoursC$20.34C$0.73
Flatbed trucks, load capacity up to 5 tons0.06Machine hoursC$27.72C$1.58
Personnel: 1 person-hour/machine-hour0.06Machine hoursC$15.14C$0.86
Windows 1 items C$1,224.21
#CodeDescriptionQtyUnitUnit PriceTotal
7MEKA_KAME_KATOPU_KAME
Installation of PVC profile window blocks in residential and public buildings: deaf with an opening area of up to 2 m2
3.0
25 m² × 0.12 = 3 m2(Windows)
m2C$322.59C$1,224.21
C$967.75 +15% C$145.16 +10% C$111.29
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 15.02hrsC$25.69C$128.97
Electricity0.34kWhC$4.07C$1.40
Waterproofing tapes, vapor-permeable butyl rubber, made of non-woven membrane-type material, with adhesive coating on the inner edges and anti-adhesive coating, beige color, width 80 mm12.54mC$22.29C$279.45
Pre-compressed self-expanding polyurethane foam sealing strips with adhesive layer on one side, width 10 mm, thickness when compressed 4 mm, thickness when expanded 20 mm0.6410 mC$145.30C$93.24
Polyurethane foam sealant (assembly foam), universal, volume 1000 ml2.07pcsC$164.80C$341.19
Steel frame mounting dowels, diameter 10 mm, length 130 (132) mm0.9210 pcsC$66.44C$60.97
Plastic mounting wedges0.24100 pcsC$239.59C$57.52
Single-mast hoists, load capacity up to 500 kg, lifting height 45 m0.05Machine hoursC$2.53C$0.13
Personnel: 1 person-hour/machine-hour0.05Machine hoursC$13.30C$0.71
Flatbed trucks, load capacity up to 5 tons0.10Machine hoursC$27.41C$2.70
Personnel: 1 person-hour/machine-hour0.10Machine hoursC$14.97C$1.47
Doors 1 items C$459.33
#CodeDescriptionQtyUnitUnit PriceTotal
8MEKA_KAME_KAPURI_KARI
Filling balcony openings in wooden log walls with caulking door blocks with door leaves: paired, opening area over 3 m2
0.8
25 m² × 0.03 = 0.75 m2(Doors)
m2C$484.14C$459.33
C$363.11 +15% C$54.47 +10% C$41.76
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 12.22hrsC$27.56C$61.18
Water0.01m3C$89.23C$0.46
Electricity0.06kWhC$14.61C$0.92
Resin-impregnated tow0.80kgC$273.82C$219.73
Self-tapping steel screws, oxidized, with countersunk head and cross-shaped slot, pointed, diameter 8 mm, length 100 mm0.00tC$269,880.99C$20.14
Edged coniferous timber (spruce, pine), natural moisture content, length RI-NE.SA m, width 20-90 mm, thickness 20-90 mm, grade III0.00m3C$34,601.01C$59.51
Flatbed trucks, load capacity up to 5 tons0.03Machine hoursC$26.11C$0.75
Personnel: 1 person-hour/machine-hour0.03Machine hoursC$14.41C$0.42
Flooring 1 items C$542.69
#CodeDescriptionQtyUnitUnit PriceTotal
9SALI_KAME_KAMEME_KAPU
Installation of bases for floor covering: from wood fiber boards on mastic in one layer with an area of more than 20 m2
21.2
25 m² × 0.85 = 21.25 m2(Flooring)
m2C$20.19C$542.69
C$429.00 +15% C$64.35 +10% C$49.34
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 15.53hrsC$22.89C$126.65
Dry-process wood fiber boards, hard T-S, group A, thickness 5 mm0.021000 m2C$3,017.37C$64.12
KN-2 rubber adhesive mastic28.26kgC$8.38C$236.80
Single-mast hoists, load capacity up to 500 kg, lifting height 45 m0.03Machine hoursC$2.37C$0.07
Personnel: 1 person-hour/machine-hour0.03Machine hoursC$12.69C$0.35
Flatbed trucks, load capacity up to 5 tons0.03Machine hoursC$25.72C$0.65
Personnel: 1 person-hour/machine-hour0.03Machine hoursC$14.27C$0.36
Bathroom 1 items C$52.25
#CodeDescriptionQtyUnitUnit PriceTotal
10NETO_KATO_KAKAME_KASARemoving wall coverings: made of glazed ceramic tiles2.5
25 m² × 0.1 = 2.5 m2(Bathroom)
m2C$16.52C$52.25
C$41.30 +15% C$6.20 +10% C$4.75
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Average work load RI.ME1.86hrsC$22.00C$40.87
Single-mast hoists, load capacity up to 500 kg, lifting height 45 m0.01Machine hoursC$2.39C$0.02
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$12.64C$0.11
Mobile screw compressors with electric motor, pressure up to 1 MPa (10 atm), capacity up to 5 m3/min0.04Machine hoursC$7.10C$0.29
Pneumatic jackhammers powered by mobile compressors0.08Machine hoursC$0.14C$0.01
Plastering 1 items C$2,035.89
#CodeDescriptionQtyUnitUnit PriceTotal
11NEME_KAME_KAKAME_KADX
Continuous leveling of interior surfaces (single-layer plastering) with dry mortar mixtures up to 10 mm thick for subseq
40.0
25 m² × 1.6 = 40 m2(Plastering)
m2C$40.23C$2,035.89
C$1,609.40 +15% C$241.41 +10% C$185.08
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Average work load RI.DX14.33hrsC$23.34C$334.58
Water0.20m3C$6,184.98C$1,269.30
Universal front-end pneumatic wheeled single-bucket loaders, nominal capacity of main bucket RI.NE m3, load capacity 5 t0.01Machine hoursC$68.31C$0.55
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$16.17C$0.13
Single-mast hoists, load capacity up to 500 kg, lifting height 45 m0.08Machine hoursC$2.36C$0.20
Personnel: 1 person-hour/machine-hour0.08Machine hoursC$12.50C$1.05
Mobile mortar mixers, drum capacity 65 l0.28Machine hoursC$0.16C$0.05
Personnel: 1 person-hour/machine-hour0.28Machine hoursC$12.50C$3.55
Painting 1 items C$199.09
#CodeDescriptionQtyUnitUnit PriceTotal
12NERI_KAME_KAKARI_KAME
Simple oil painting of previously painted walls: without preparation, with removal of old paint up to 10%
40.0
25 m² × 1.6 = 40 m2(Painting)
m2C$3.93C$199.09
C$157.38 +15% C$23.61 +10% C$18.10
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 15.40hrsC$24.44C$131.99
Colored cotton rags0.06kgC$367.75C$23.81
Single-mast hoists, load capacity up to 500 kg, lifting height 45 m0.04Machine hoursC$2.40C$0.09
Personnel: 1 person-hour/machine-hour0.04Machine hoursC$12.82C$0.51
Flatbed trucks, load capacity up to 5 tons0.02Machine hoursC$26.06C$0.63
Personnel: 1 person-hour/machine-hour0.02Machine hoursC$14.42C$0.35
Electrical 1 items C$401.79
#CodeDescriptionQtyUnitUnit PriceTotal
13KAVO_KASA_KAPUME_KAMEm
Electrical wiring in chambers: cable or wire with band fasteners
75.0
25 m² × 3 = 75 m(Electrical)
mC$4.23C$401.79
C$317.62 +15% C$47.64 +10% C$36.53
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 110.54hrsC$26.69C$281.47
Electricity0.72kWhC$0.30C$0.21
Plastic mounting tapes for wire bundling, fastened with plastic buttons, width 10 mm0.2310 mC$2.51C$0.57
Polypropylene expansion anchors0.77100 pcsC$2.18C$1.67
Copper cable lugs for electrical installations0.01100 pcsC$540.07C$8.10
Mobile cranes, lifting capacity 16 t0.19Machine hoursC$65.70C$12.32
Personnel: 1 person-hour/machine-hour0.19Machine hoursC$19.02C$3.56
Non-tipping wagons, capacity TO.TO m30.23Machine hoursC$0.83C$0.19
Flatbed trucks, load capacity up to 10 tons0.19Machine hoursC$36.63C$6.87
Personnel: 1 person-hour/machine-hour0.19Machine hoursC$14.16C$2.65
Plumbing 1 items C$926.24
#CodeDescriptionQtyUnitUnit PriceTotal
14MENE_KATO_KAKARI_KARI
Laying water supply pipelines using multilayer metal-polymer pipes with a diameter of: 20 mm
20.0
25 m² × 0.8 = 20 m(Plumbing)
mC$36.61C$926.24
C$732.21 +15% C$109.83 +10% C$84.20
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 120.60hrsC$27.31C$562.66
Water0.09m3C$114.86C$10.61
Electricity0.47kWhC$18.81C$8.84
Corrugated protective pipes2.20mC$66.34C$146.14
Tower cranes, lifting capacity 8 t0.01Machine hoursC$41.62C$0.34
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$19.18C$0.15
Mobile cranes, lifting capacity 16 t0.01Machine hoursC$66.30C$0.39
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$19.18C$0.11
Flatbed trucks, load capacity up to 5 tons0.07Machine hoursC$25.75C$1.91
Personnel: 1 person-hour/machine-hour0.07Machine hoursC$14.28C$1.06
Heating 1 items C$523.28
#CodeDescriptionQtyUnitUnit PriceTotal
15MENE_KARI_KAKAME_KARI
Laying heating pipelines made of steel water and gas pipes, non-galvanized, with a diameter of: 20 mm
50.0
25 m² × 2 = 50 m(Heating)
mC$8.27C$523.28
C$413.66 +15% C$62.05 +10% C$47.57
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 114.85hrsC$26.83C$398.45
Technical gaseous oxygen0.14m3C$6.62C$0.92
Water0.22m3C$1.82C$0.40
Linen thread0.03kgC$7.72C$0.23
MA-0115 oil paint, mummy, iron minium0.22kgC$5.15C$1.13
Tower cranes, lifting capacity 8 t0.04Machine hoursC$41.47C$1.66
Personnel: 1 person-hour/machine-hour0.04Machine hoursC$19.12C$0.76
Mobile cranes, lifting capacity 16 t0.04Machine hoursC$66.05C$2.31
Personnel: 1 person-hour/machine-hour0.04Machine hoursC$19.12C$0.67
Flatbed trucks, load capacity up to 5 tons0.17Machine hoursC$25.65C$4.49
Personnel: 1 person-hour/machine-hour0.17Machine hoursC$14.23C$2.49
Gas welding and cutting equipment0.57Machine hoursC$0.22C$0.13
Insulation 1 items C$1,832.32
#CodeDescriptionQtyUnitUnit PriceTotal
16RINE_KAME_KANETO_KAME
Insulation of interior walls on wood with spray guns using liquid thermal insulation coating 1 mm thick
13.8
25 m² × 0.55 = 13.75 m2(Insulation)
m2C$105.34C$1,832.32
C$1,448.48 +15% C$217.27 +10% C$166.57
Labor Materials Equipment
TypeResourceQtyUnitUnit PriceCost
Worker Category 12.49hrsC$25.73C$64.08
Water0.00m3C$484.35C$2.48
Electricity1.02kWhC$79.32C$82.00
Antiseptic for protecting wooden building structures from biological decay0.00tC$945,530.99C$1,299.64
Flatbed trucks, load capacity up to 5 tons0.01Machine hoursC$26.06C$0.18
Personnel: 1 person-hour/machine-hour0.01Machine hoursC$14.29C$0.09
Cost Summary
Direct Cost79%C$16,875.39
Overhead+15%C$2,531.30
Profit+10%C$1,940.66
Grand TotalC$21,347.35

Resource Summary

54 resourcesiAggregated materials, labor, and equipment needed for the entire project
Materials to Order (34)
ResourceUnitQtyUnit PriceCost
Edged coniferous timber (spruce, pine), natural moisture content, lengm30.12C$36,012.60C$4,400.74
Waterm32.02C$1,294.03C$2,615.10
Antiseptic for protecting wooden building structures from biological dt0.00C$928,314.29C$1,299.64
Masonry mortar, cement-lime, M25m30.10C$11,041.05C$1,159.31
Polyurethane foam sealant (assembly foam), universal, volume 1000 mlpcs2.07C$164.83C$341.19
Waterproofing tapes, vapor-permeable butyl rubber, made of non-woven mm12.54C$22.28C$279.45
Edged softwood boards, natural moisture content, length RI-NE.SA m, wim30.01C$24,618.37C$241.26
KN-2 rubber adhesive mastickg28.26C$8.38C$236.80
Resin-impregnated towkg0.80C$273.81C$219.73
Corrugated protective pipesm2.20C$66.43C$146.14
ElectricitykWh2.69C$35.11C$94.55
Pre-compressed self-expanding polyurethane foam sealing strips with ad10 m0.64C$145.23C$93.24
Construction nailst0.00C$218,950.00C$87.58
Galvanized sheet steel, thickness KA.LI mmt0.01C$16,810.00C$84.05
Hot-rolled wire in coils, diameter NE.TO-NE.SA mmt0.00C$190,950.00C$76.38
Anthracene oilt0.00C$34,131.82C$75.09
Dry-process wood fiber boards, hard T-S, group A, thickness 5 mm1000 m20.02C$3,010.33C$64.12
Polyethylene film, thickness KA.MESA mmm21.86C$34.31C$63.80
Steel frame mounting dowels, diameter 10 mm, length 130 (132) mm10 pcs0.92C$66.42C$60.97
Plastic mounting wedges100 pcs0.24C$239.67C$57.52
Edged softwood board, natural moisture content, length RI-NE.SA m, widm30.00C$17,445.00C$34.89
Ready-mixed masonry mortar, cement, M100m30.03C$1,109.63C$29.96
Light wire, diameter ME.ME mmt0.00C$93,966.67C$28.19
Colored cotton ragskg0.06C$372.03C$23.81
Self-tapping steel screws, oxidized, with countersunk head and cross-st0.00C$201,400.00C$20.14
Galvanized steel washers, round, hole diameter M16-24kg0.36C$49.61C$17.71
Steel roofing nails, diameter 2-3 mm, length 20-40 mmkg0.78C$20.41C$15.92
Copper cable lugs for electrical installations100 pcs0.01C$540.00C$8.10
Quicklime, grade It0.00C$22,766.67C$6.83
Polypropylene expansion anchors100 pcs0.77C$2.18C$1.67
Grand TotalC$11,886.73
Labor Requirements (5)
ResourceUnitQtyUnit PriceCost
Worker Category 1hrs136.93C$31.50C$4,313.98
Average work load RI.DXhrs14.33C$23.34C$334.58
Personnel: 1 person-hour/machine-hourMachine hours4.63C$25.80C$119.50
Average work load RI.MEhrs1.86C$22.00C$40.87
Personnel: 3 man-hours/machine-hoursMachine hours0.01C$114.29C$0.80
Grand TotalC$4,809.73
Equipment Requirements (15)
ResourceUnitQtyUnit PriceCost
Tower cranes, lifting capacity 8 tMachine hours3.08C$32.61C$100.47
Single-bucket electric walking excavators with dragline working equipmMachine hours0.01C$4,738.57C$33.17
Mobile cranes, lifting capacity 16 tMachine hours0.29C$66.60C$19.18
Flatbed trucks, load capacity up to 5 tonsMachine hours0.50C$26.34C$13.13
Flatbed trucks, load capacity up to 10 tonsMachine hours0.19C$36.64C$6.87
Universal front-end pneumatic wheeled single-bucket loaders, nominal cMachine hours0.04C$70.00C$3.15
Trucks, load capacity up to 8 tonsMachine hours0.03C$37.27C$1.01
Single-mast hoists, load capacity up to 500 kg, lifting height 45 mMachine hours0.21C$2.39C$0.51
Deep vibratorsMachine hours0.72C$0.56C$0.40
Bulldozers, power 79 kW (108 hp)Machine hours0.01C$50.00C$0.35
Mobile screw compressors with electric motor, pressure up to 1 MPa (10Machine hours0.04C$7.07C$0.29
Non-tipping wagons, capacity TO.TO m3Machine hours0.23C$0.82C$0.19
Gas welding and cutting equipmentMachine hours0.57C$0.23C$0.13
Mobile mortar mixers, drum capacity 65 lMachine hours0.28C$0.18C$0.05
Pneumatic jackhammers powered by mobile compressorsMachine hours0.08C$0.12C$0.01
Grand TotalC$178.91

Material Alternatives

iAlternative materials with approximate price difference. Percentages show material cost change relative to the current specification.
Insulation of interior walls on wood with spray guns usC$1,384.13
XPS foam board+30%Cellulose fiber-15%Spray foam+50%
Installation of PVC profile window blocks in residentiaC$833.77
Triple-glazed PVC+35%Aluminum frame+25%Timber frame+45%
Construction of reinforced concrete floors and slabs upC$602.93
High-strength concrete+20%Lightweight concrete+15%Recycled aggregate-10%
Construction of strip foundations: concreteC$340.31
High-strength concrete+20%Lightweight concrete+15%Recycled aggregate-10%
Installation of bases for floor covering: from wood fibC$300.92
Vinyl/LVT-35%Natural stone+100%Polished concrete-30%
Laying water supply pipelines using multilayer metal-poC$165.59
Copper pipe+120%PEX pipe-15%Stainless steel+200%

Risk Analysis

Monte Carlo · 10KiMonte Carlo simulation (10,000 iterations) showing completion probability at different confidence levels
103days
P50
50% probability the project finishes within this timeframe. Median scenario based on Monte Carlo simulation.
107days
P80
80% probability — recommended planning basis. Accounts for common delays and uncertainties.
111days
P95
95% probability — conservative estimate. Covers nearly all risk scenarios including severe delays.
+11days
Buffer
Recommended time buffer to add to the deterministic schedule. Covers typical construction uncertainties.
Base Cost (P50)
C$21,347.35
Budget (P80)
C$22,150.54
Maximum (P95)
C$22,920.27
Contingency
+3.8%
Recommended cost reserve based on schedule risk analysis — C$803.19
Recommended Budget: C$22,150.54
Deterministic 96 days
P50 103 days
P80 107 days
P95 111 days
P50 P80 P95
Based on Monte Carlo simulation with 10,000 iterations using PERT distribution for each phase duration.
Peak: 6
158 man-hours
12 crit. phases

Cost Risk Analysis

Monte Carlo · 10,000 iterations

Monte Carlo simulation of construction cost uncertainty

Cost Percentiles

C$26,560.57
P10
C$26,920.92
P25
C$27,376.36
P50
C$27,972.22
P80
C$28,268.48
P90

Cumulative Probability (S-Curve)

+2.2%
Recommended Contingency (P80 − P50)
Reserve to cover likely cost overruns with 80% confidence — C$595.86

Top Risk Drivers

CategoryWork ItemRisk Share
Internal WallsLimestone partition wall masonry: unreinforced wit
65.1%
External WallsMasonry of external and internal brick walls with
18.6%
InsulationInsulation of interior walls on wood with spray gu
4.8%
PlasteringContinuous leveling of interior surfaces (single-l
3.3%
PlumbingLaying water supply pipelines using multilayer met
2.1%
WindowsInstallation of PVC profile window blocks in resid
2.0%
StructureConstruction of reinforced concrete floors and sla
1.4%
FoundationConstruction of strip foundations: concrete
0.7%

Sensitivity Analysis

±10%iImpact of ±10% change in each cost component on the total project cost

This tornado chart shows how a ±10% change in each cost category affects the total estimate. The wider the bar, the greater the cost impact — helping identify which cost drivers carry the most risk and where tighter cost control may be needed.

Decrease ← → IncreaseImpact
Materials56% of total
±C$1,188.67±5.6%
Labor23% of total
±C$480.98±2.3%
Overhead12% of total
±C$253.13±1.2%
Profit9% of total
±C$194.07±0.9%
Equipment1% of total
±C$17.89±0.1%

Cost Summary

iFinal cost breakdown with direct costs, overhead, profit, and grand total
LaborC$4,809.7722%
MaterialsC$11,886.7456%
EquipmentC$178.881%
Direct CostC$16,875.39
OverheadC$2,531.3012%
ProfitC$1,940.669%
Grand TotalC$21,347.35100%
EUR equivalent€13.317,12
USD equivalent$15,347.99
GBP equivalent£11,619.59

Estimate Classification

AACE 18R-97

AACE International Recommended Practice 18R-97

3
ClassClass 3
Typical PurposeBudget Authorization
Expected Accuracy Range: -20% / +30%
Project Definition Level: 10–40%

Cost Benchmark

Residential · North America

Comparison of estimated cost/m² against market reference ranges

Low
1,500
▲ Typical
2,200
High
3,500
▼ Your Estimate
544 EUR/m²
Significantly below range · 0.25x ratio to typical

Methodology & Assumptions

iCalculation methodology, data sources, and key assumptions underlying this estimate
Data SourceDDC Pricing DB — English
Confidence Level50%
Overhead Rate15%
Profit Rate10%
Items Matched16
Assumptions
  • Costs adjusted by location-specific labor, material, and equipment factors
  • Exchange rates are offline reference rates and may differ from market rates
  • All amounts exclude VAT / sales tax
  • This estimate is for preliminary budgeting only — not a binding quotation
Included in Estimate
  • All labor, materials, and equipment per defined scope
  • Overhead and profit margins as specified
  • Location-adjusted pricing factors applied
Excluded from Estimate
  • VAT / sales tax
  • Permits, licenses, and legal fees
  • Temporary works and site facilities
  • Design and engineering fees
Prices current as of 2026-03-16 · No cost escalation or inflation adjustment applied

Frequently Asked Questions

How much does House Extension / Addition cost?
The cost depends on your location, materials chosen, and project scope. Use our calculator with your specific city to get an instant estimate based on 36 verified work items from our database of 55,719 construction prices.
What work items are included in this estimate?
This BOQ includes 36 work items covering Demolition & Preparation, Foundations & Structure, Roof (Flat), Openings & External Finishes, Internal Finishes, MEP. Each item is matched to unit rates from our verified pricing database spanning 9 languages and 36 locations worldwide.
How long does House Extension / Addition take?
Duration depends on project size and complexity. A typical 25 m² project takes approximately 6 weeks. Our calculator generates a detailed Gantt chart with phase-by-phase scheduling.
How accurate is this estimate?
Our estimates use verified construction pricing data with location-specific adjustments (PPP factors). The Monte Carlo simulation provides P10-P90 confidence intervals. For formal budgeting, we recommend a Class 3 AACE estimate with local contractor quotes.
What does a house extension / addition include?
Cost estimate for a 30 m² ground-floor house extension. Covers foundation underpinning or new strip footing, structural opening in existing wall (RSJ/steel beam), masonry or timber frame walls, flat or pitched roof, matching exterior finishes, MEP extension, interior finishing, and building control compliance.

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