---
title: "Cost comparison worksheet"
url: https://digiconsoo.com/page17
description: "A worked comparison of conventional site framing against delivered assemblies across a 26-house development."
---

# Cost comparison worksheet

[Main page](https://digiconsoo.com/) › Cost comparison

A developer built 26 high-end houses. Previous similar developments produced the figures below. Skilled labour cost this particular developer 56.00 per hour and helpers 29.00 per hour; those are not the paid wages but numbers that encompass all costs associated with employing the personnel.

Worksheet

**Development**: 26 high-end houses

**Skilled labour**: 56.00 per hour

**Helper**: 29.00 per hour

**Elements per house**: 2 bay windows, groin vault, elliptical dome, cove

**Conventional total**: 9,679.00

**Fabricated total**: 6,718.00

Each home had two bay windows, a groin vault in the wine cellar, an elliptical dome in the foyer, and a large cove detail in the master bedroom.

## Conventional site framing

*Recorded labour and material for the four elements.*

| Element | Labour | Materials | Total |
|---|---|---|---|
| Bay window framing | Carpenter and helper, 26 hrs | 166.00 | 2,376.00 |
| Groin vault | Carpenter and helper, 32 hrs | 320.00 | 3,040.00 |
| Dome | Carpenter and helper, 22 hrs | 290.00 | 2,160.00 |
| Cove | Carpenter and helper, 19 hrs | 288.00 | 1,903.00 |
| Total | — | — | 9,679.00 |

## Delivered assemblies

Complete precision parts and assemblies arrive at the job. Across 26 houses there is significant economy of scale, since engineering and tooling costs are spread out.

*Recorded delivered cost for the same four elements.*

| Element | Site labour | Unit and delivery | Total |
|---|---|---|---|
| Bay window framing | 1 carpenter, 2 hrs | 825.00 | 1,999.00 |
| Groin vault | Carpenter and helper, 4 hrs | 1,125.00 | 1,465.00 |
| Dome | Carpenter and helper, 4 hrs | 1,448.00 | 1,788.00 |
| Cove | Carpenter and helper, 6 hrs | 956.00 | 1,466.00 |
| Total | — | — | 6,718.00 |

The bay window framing arrives pre-sheathed as a unit, ready to roof, and takes one carpenter two hours to install; the total above includes 224.00 of labour and an hour of all-terrain forklift at 125.00. The groin vault and the cove arrive as flat pack parts, predrilled for pocket screws and numbered with assembly drawings. The dome comes as a unit, ready for wire and plaster.

## Difference

Across the four elements the recorded difference per house is 2,961.00, before counting the framing weeks that the delivered assemblies free up elsewhere on the schedule.

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