THE ESTIMATING ANSWER
For one wet garden run, start with a defined scope and measurement basis. Record run length, trench depth, fall, soil conditions and discharge location. Separate perforated pipe, aggregate and geotextile quantities from digging and reinstatement. Price the listed tasks separately and state the condition that would require a revision: Unexpected utilities or no feasible outlet can stop the base design.
This guide uses a fictional project in Red Deer, Alberta: One wet garden run. Its matching estimate and PDF give each scope decision a visible CAD cost line. Use the document to understand the structure; verify the actual building, product schedule, labour and supplier inputs before preparing a client quote.
1. Define the measured job
Install a shallow subsurface drain across an accessible garden run and connect it to a confirmed lawful discharge point. Record run length, trench depth, fall, soil conditions and discharge location. Record the measurements and existing condition in the estimate before turning quantities into line items. The scope should make clear why this is a separate project from a broader renovation or maintenance quote.
Measurement basis: Record run length, trench depth, fall, soil conditions and discharge location.
2. Build a product and labour schedule
Separate perforated pipe, aggregate and geotextile quantities from digging and reinstatement. This example has 7 distinct lines, including drain route survey, service check and protection, trench excavation. Use actual supplier prices and labour inputs for a customer job; the displayed amounts are fictional document inputs.
Selections to confirm: Separate perforated pipe, aggregate and geotextile quantities from digging and reinstatement.
3. Sequence the work and handoffs
Trace buried services and confirm discharge before excavation. Show which task depends on access, a selected product or another trade. If that dependency is still open, label the price preliminary and identify the information needed before a firm quote.
Work sequence: Trace buried services and confirm discharge before excavation.
4. Set a change boundary
Unexpected utilities or no feasible outlet can stop the base design. The example excludes basement waterproofing, drainage approval or major landscape reconstruction. Record the discovery, agree the revised work and update the estimate before adding it to the job.
If the job changes: Unexpected utilities or no feasible outlet can stop the base design.
Review the Canadian job address
Verify the existing water, waste and fixture connections on site. Confirm who handles any required trade work, approvals and inspections for this address; this fictional document does not decide them.
The trench excavation line uses 90 linear ft., approximately 27.43 m. Check the route, cuts and supplier unit before setting a real quantity. The example amounts are fictional CAD document inputs, not current rates for Red Deer, Alberta or another community. A site visit and current supplier information are needed to replace them.
Work through the itemized calculation
Check each extension of quantity and rate in the paired PDF. Two lines from this project are:
- Trench excavation: 90 linear ft. × C$18.00 = C$1,620.00.
- Perforated pipe allowance: 90 linear ft. × C$9.60 = C$864.00.
Adding all 7 rounded line amounts gives C$5,554.00. The PDF shows 0% tax and the same total before any markup. The sample shows 0% tax only to make the arithmetic visible. Determine any applicable GST, HST or PST and markup for the actual work before sharing a quote.
| Work item | Quantity | Unit rate | Amount |
|---|---|---|---|
| Drain route survey | 1 job | C$250.00 | C$250.00 |
| Service check and protection | 1 job | C$190.00 | C$190.00 |
| Trench excavation | 90 linear ft. | C$18.00 | C$1,620.00 |
| Perforated pipe allowance | 90 linear ft. | C$9.60 | C$864.00 |
| Stone and fabric allowance | 1 job | C$745.00 | C$745.00 |
| Pipe bedding and connection | 90 linear ft. | C$14.00 | C$1,260.00 |
| Backfill and turf reinstatement | 1 job | C$625.00 | C$625.00 |
| Illustrative subtotal | C$5,554.00 | ||
Scope and pricing boundaries
Install a shallow subsurface drain across an accessible garden run and connect it to a confirmed lawful discharge point.
Outside this example: No basement waterproofing, drainage approval or major landscape reconstruction.
Keep the product allowance, installation work and any unresolved condition visible as separate decisions. If access or the selected product changes, update the affected quantity or rate and explain the revision before the client relies on the estimate.
Before you send the estimate
- Record run length, trench depth, fall, soil conditions and discharge location.
- Separate perforated pipe, aggregate and geotextile quantities from digging and reinstatement.
- Trace buried services and confirm discharge before excavation.
- Unexpected utilities or no feasible outlet can stop the base design.
Check the business, client, property, dates, line extensions and notes. The subsurface garden drain installation PDF example shows one way to present them. Its short PDF note lists the brief's scope exclusions; the fuller project limits above should guide your own scope.
Questions about this estimate
Which quantity controls this subsurface garden drain installation estimate?
Record run length, trench depth, fall, soil conditions and discharge location.
When should this subsurface garden drain installation quote be revised?
Unexpected utilities or no feasible outlet can stop the base design. No basement waterproofing, drainage approval or major landscape reconstruction.
MAKE THE NEXT ESTIMATE YOUR OWN
Build a subsurface garden drain installation estimate.
Enter the job scope in Estimates on iPhone or Android or start from an AI-assisted draft. Check every quantity, rate, allowance, client detail and note before exporting the PDF. Some app features may require an in-app purchase.
