Section 278 works or a section 38 adoption agreement
Most schemes need both a section 278 for the site access and a section 38 for the estate roads. What each secures, what they cost, and how they interact with an occupation condition.
The choice between a section 278 or section 38 agreement is not really a choice. Section 278 of the Highways Act 1980 covers works to highway that already exists, and section 38 covers the adoption of new highway you are building. Most residential schemes of any size need both: a section 278 for the site access onto the existing road, and a section 38 for the estate streets inside the site. Getting that clear early matters, because the two agreements run on different timescales and one of them can hold up your first occupation.
Both sit outside the planning permission. Neither is granted by the planning authority unless it happens to be a unitary authority that is also the highway authority, and even then the teams and the timescales are separate.
Works to existing highway against new highway
A section 278 agreement lets the highway authority agree that works to the public highway can be carried out at your expense. The classic examples are a new priority junction, a ghost island right turn, a signalised access, a pedestrian crossing, footway widening, a bus stop relocation or a dropped kerb on a classified road. The authority remains the highway authority throughout, and the works become part of the public highway as soon as they are finished.
A section 38 agreement is for streets you construct that you want to become maintainable at public expense. The developer builds to the authority's standard specification, the authority inspects, a maintenance period runs, and adoption follows. Until adoption the street is private and you maintain it.
Which authority you are dealing with depends on the road. County councils and unitary authorities are the local highway authority for most roads. National Highways deals with the strategic road network, where the design standards are the Design Manual for Roads and Bridges and the policy position on development is set out in national circular guidance. Transport for London handles the network it manages in London. A scheme touching a trunk road takes longer, so front-load it.
| Section 278 | Section 38 | |
|---|---|---|
| Applies to | Works to existing highway | New streets to be adopted |
| Who owns the land | Highway authority, or land to be dedicated | Developer, until dedication |
| Typical trigger | Site access, junction, crossing | Estate roads, shared surfaces, footways |
| Security | Bond or cash deposit for the works | Bond covering construction and maintenance |
| Fees | Design check and supervision, per the published schedule | Design check and supervision, per the published schedule |
| End point | Works certified complete | Adoption after the maintenance period |
What each agreement actually secures
A section 278 secures the authority's control over work in its own highway. It sets the design, the specification, the traffic management arrangements, the programme window, the inspection regime, the indemnities and the insurance. It also usually requires you to pay a commuted sum for anything non-standard you are leaving behind for the authority to maintain: unusual paving, structures, non-standard lighting columns, planting.
A section 38 secures the standard of construction and a financial guarantee. The authority is being asked to take on a perpetual maintenance liability, so it wants the road built to specification, drainage that works, adequate visibility, and a bond that pays for completion if you go under mid-build.
Read the draft agreement for the trigger dates rather than the technical schedules first. Those dates are what interact with your planning conditions.
Bonds, fees and commuted sums
Three categories of money, and developers routinely budget for only one.
The bond, or a cash deposit in lieu, covers the authority's cost of completing the works if you do not. It is set against the estimated cost of the works and usually released in stages, with a retained portion held through the maintenance period.
Fees cover design checking and site supervision by the authority's engineers. Every authority publishes a fee basis, normally a percentage of works value with a minimum, and you should read the current published schedule rather than assuming last year's figure. These are not negotiable in most authorities.
Commuted sums cover future maintenance of anything the authority would not otherwise have to maintain. Structures are the big one: a retaining wall holding up an adopted footway, a culvert, a bridge over a watercourse. Sums for structures can be substantial and they are calculated on a whole life basis, so ask for the calculation early. Where a scheme is being tested for viability, these costs belong in the appraisal alongside the obligations, a point we touch on in viability assessment or affordable housing statement.
Technical approval and inspection
Technical approval is a separate process from the agreement itself. Drawings go in, the authority's engineers check them against the local specification and the relevant national standards, and comments come back. Two or three rounds is normal. Structures need a technical approval schedule and an approval in principle before detailed design is accepted.
Road safety audits sit in this process. For most local authority schemes a stage 1 audit at design and a stage 3 audit after construction are expected, with the designer's response to each recorded. On the strategic road network the audit regime follows the national standard and is applied strictly.
Site supervision follows the agreement. Expect hold points where work cannot continue until inspected, particularly for subgrade, sub-base, drainage and surfacing. Missing a hold point can mean opening up finished work.
Programme effects on your planning conditions
This is where the two agreements bite on your development. Access works are almost always secured by a condition preventing occupation, and sometimes preventing the start of works, until the access has been constructed. If the section 278 is not signed, the works cannot start, and if the works cannot start, the condition cannot be discharged.
Three programme facts to build into your cashflow:
- A section 278 agreement, from first submission of drawings to a signed agreement, commonly takes several months, and longer where a structure or signals are involved.
- Works in the highway need a traffic management window agreed with the network coordination team, which may exclude school terms, retail trading periods or other works nearby.
- Adoption under section 38 follows a maintenance period after practical completion, so the street stays private, and your maintenance liability continues, well past the last house being sold.
Where the highway works are extensive, the construction traffic itself becomes a planning matter, which is what a Construction Traffic Management Plan deals with. And where the access design was the subject of capacity or safety argument at application stage, the assumptions in the Transport Assessment need to match what the section 278 drawings actually show. Inconsistency between the two is a common reason for a technical approval round going badly.
Who maintains what afterwards
Sort this out on a plan, not in correspondence. Colour up the adopted highway, the section 278 works, the private drives, the shared surfaces that will stay private, the drainage owned by the water undertaker under a separate adoption agreement, and the landscaped areas going to a management company.
Highway drainage inside the adopted extent goes to the highway authority. Foul and surface water sewers offered for adoption go to the sewerage undertaker under a separate agreement, which runs on its own timetable. Attenuation features serving both often end up with the management company, and that split needs to be settled before the first plot sells, because conveyancing will expose it.
Getting both moving early
The pattern on schemes that run smoothly looks like this. Highway design is developed alongside the planning application rather than after it. A pre-application meeting with the highway authority's development management engineer happens before the layout is fixed. Technical approval submission goes in shortly after permission, with the agreement drafting running in parallel. Bonds are priced with the funder at the same time.
The pattern on schemes that stall is a permission granted in March, a first submission of section 278 drawings in September, and a developer discovering in November that the junction needs a departure from standards and a road safety audit response before anyone will sign anything.
One honest uncertainty: fee percentages, bond calculation methods and commuted sum formulas vary between authorities, and some publish them more clearly than others. Ask for the current figures in writing at pre-application stage and hold the email.
Browse all 66 PlanScope report types and start a draft, then check which of the transport documents your scheme is likely to need.
This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.
Frequently asked questions
Do I need both a section 278 and a section 38?
On most residential schemes, yes. Section 278 of the Highways Act 1980 covers alterations to the existing public highway, typically the site access, while section 38 covers adoption of the new streets you build inside the site. A scheme using only a private drive off an existing road may need only the section 278.
How long does a section 278 agreement take?
Commonly several months from first submission of drawings to signature, and longer where signals, a structure or a departure from standards is involved. Technical approval usually runs two or three rounds of comments. Schemes on the strategic road network take longer again, so the process should start alongside the planning application.
What is a commuted sum for?
Future maintenance of anything the highway authority would not otherwise have to maintain: structures such as retaining walls and culverts, non-standard surfacing, unusual lighting or planting. Sums are calculated on a whole life basis and can be large, so ask for the calculation method at pre-application stage rather than after the layout is fixed.
When does a new estate road become publicly maintained?
At adoption, which follows practical completion and a maintenance period during which you remain responsible for defects. Until then the street is private, so the maintenance liability and the management arrangements need to be set out clearly for plot purchasers and their conveyancers.
Can a planning condition be discharged before the agreement is signed?
Not usually, where the condition requires the access works to be built. No agreement means no lawful works in the highway, which means the condition cannot be satisfied. That chain is why access conditions preventing occupation are the ones most likely to delay a first handover.
Who deals with sewers and drainage adoption?
Highway drainage within the adopted extent goes to the highway authority. Foul and surface water sewers offered for adoption are dealt with by the sewerage undertaker under a separate agreement on its own timetable. Attenuation features serving both often remain with a management company, so settle the split on a plan early.
Sources and further reading
This article is general guidance about the planning system in England and, where stated, the rest of the UK. It is not legal or professional advice. Check your local planning authority’s validation requirements and take professional advice for your specific site.