Driveway drainage should start with the source and destination of the water. A channel without a suitable outfall can simply move the problem. Use the dedicated calculator to explore a guide budget for the work described below.
Estimate driveway drainage from the measurements and work options below. Guide allowances are already included; a contractor’s quote is not required to use the tool.
The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions.
Guide model reviewed 7 November 2026. VAT treatment varies between published guides and supplier quotes; no VAT is added automatically. Add it only where your allowances exclude it.
The calculation separates the measured run, a basic system allowance where selected, and any connection work you enter. Infiltration testing, storage design, abnormal ground, permissions and engineered attenuation may require additional work beyond the guide.
View the published guide used for the main allowance. Optional allowances are budgeting estimates and can differ from a site-specific quotation.
Use a measured specification to compare prices for your property. Ask contractors to confirm the work, preparation, materials, access, disposal and any exclusions before agreeing a price.
Driveway Drainage planned around your property
Driveway drainage should start with the source and destination of the water. A channel without a suitable outfall can simply move the problem.
The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions.
Driveway drainage should start with the source and destination of the water. A channel without a suitable outfall can simply move the problem.
The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions.
Measure each proposed run in metres and add the lengths together. Include returns and changes of direction in your measured scope. Only enter an additional connection or removal allowance when that work is outside the installed guide rate.
The calculation separates the measured run, a basic system allowance where selected, and any connection work you enter. Infiltration testing, storage design, abnormal ground, permissions and engineered attenuation may require additional work beyond the guide.
The first guide option is trench and pipe drainage guide. Its allowance is £35–£70 for the relevant unit shown in the result. This is a published-guide starting point; it is not a price offered by a contractor on this website.
The available work options are trench and pipe drainage guide; domestic channel drainage. Select the one that matches the proposed scope before comparing the result.
The project controls include:
The results show the measured quantity, the selected work allowance and any separately selected items. A volume, unit count or coverage result is a quantity check, not a construction design. Where the model uses a minimum visit allowance or whole bags, the displayed total will not fall in direct proportion to a very small area.
Use the optional contingency to make a separate budget provision. Add a quoted fixed allowance only for work outside the model’s stated scope. Check the VAT basis before selecting the VAT adjustment.
Give contractors the same measurements and work description. Ask them to identify the main work, preparation, disposal, access requirements, drainage and any making-good that applies to this project. An apparent saving can simply mean that a different part of the scope has been priced.
The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions. Keep the agreed specification with the quote, including any exclusions and the way changes discovered during the work will be authorised.
Examples use the specification named on each card, the calculator’s example measurements and guide allowances. Optional extras, contingency and VAT adjustment are off. Supply-only models exclude installation.
The calculation separates the measured run, a basic system allowance where selected, and any connection work you enter. Infiltration testing, storage design, abnormal ground, permissions and engineered attenuation may require additional work beyond the guide.
Measure each proposed run in metres and add the lengths together. Include returns and changes of direction in your measured scope. Only enter an additional connection or removal allowance when that work is outside the installed guide rate.
Driveway drainage should start with the source and destination of the water. A channel without a suitable outfall can simply move the problem. The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions.
The figures are early budgeting allowances for the work described in the selected option. The measured run and an optional soakaway allowance help budget installation, but do not size pipes or establish discharge permissions. Ask a contractor to confirm the measured scope, access, preparation, materials and exclusions after assessing the property. The written quotation, rather than the calculator, establishes the work and the agreed price.
The result separates the main work from selected options and any additional allowance you enter. Add a basic soakaway guide (£377–£793; subject to assessment). Do not add an item again if the main rate or contractor’s quote already includes it. Contingency is optional and is shown separately.
No extra VAT is added automatically. Published cost guides and supplier prices can use different VAT bases, so check the source and any written quotation. The optional VAT control adds 20% to the calculated allowances only when you select it. Leave it off when the rates or quotation already include VAT to avoid counting tax twice.
