Highway Assessments for Change of Use Applications – A Practical Guide for Developers
What highway matters to consider when land or buildings change use.
A change of use can have transport implications even where very little physical development is proposed.
A building may already have an established use, but a new occupier or activity can change the number of vehicle movements, parking demand, servicing requirements or the way an access operates. For this reason, the Highway Authority may ask for supporting transport information as part of a planning application.
The important point is that the proposed use should normally be considered against the lawful existing use of the site. The assessment is therefore often about understanding what changes from the existing position rather than simply assessing the new use in isolation.
What Will the Highway Authority Consider?
The issues will depend on the site and the nature of the proposed use, but commonly include:
whether the existing access remains suitable;
whether sufficient parking is available;
whether vehicles can enter, leave and manoeuvre safely;
how deliveries and servicing will operate;
whether the proposed use is likely to materially increase traffic; and
whether the site is accessible by walking, cycling and public transport.
For many change of use applications, these matters can be addressed without the need for extensive traffic modelling.
Existing Use Matters
One of the first things to establish is the lawful existing use of the property. This is important because an existing building may already have the potential to generate traffic, parking and servicing movements. A building being vacant at the time of the application does not necessarily mean that the transport assessment should assume a zero-traffic starting point.
Understanding the existing use can therefore be critical when assessing whether the proposed change would result in a meaningful increase in highway impact.
Parking
Parking is often one of the main issues associated with a change of use.
Different uses can generate different levels of demand and may have very different patterns of occupation during the day.
The assessment may consider the amount of parking available, the relevant Council standards, likely demand from staff and visitors, and whether there are realistic alternatives to travelling by car.
Where parking provision is limited, a site-specific assessment can help establish whether the proposed use can operate satisfactorily.
Access and Vehicle Movement
An existing access may have been perfectly adequate for the previous use but still need to be reviewed if the nature or frequency of vehicle movements changes.
This can include consideration of visibility, access width, internal circulation, parking manoeuvres and the ability of delivery or refuse vehicles to use the site safely.
Vehicle tracking may be required where space is constrained or larger vehicles need to manoeuvre within the site.
Deliveries and Servicing
A change of use can also alter how frequently a site receives deliveries and the type of vehicles involved.
The planning submission may therefore need to explain where deliveries will take place, how vehicles will turn or leave the site and whether servicing can occur without obstructing other users or the public highway.
Do I Need a Transport Assessment?
Not every change of use requires a full Transport Assessment. For many smaller developments, a Transport Statement or short Transport Technical Note can provide the necessary evidence.
The appropriate level of assessment depends on the scale of the development, the difference between the existing and proposed uses and whether there are any specific highway concerns.
Traffic surveys are not automatically required. They should normally be commissioned where they are necessary to address a specific issue, such as parking demand, traffic speeds or the operation of a nearby junction.
Getting Advice Early
Transport issues are usually easier to resolve before an application is submitted. An early review can establish whether the existing access is suitable, whether parking is likely to be acceptable and whether any surveys or vehicle tracking are required. It can also prevent unnecessary work by ensuring that the level of transport assessment is appropriate to the scale of the proposal.
DW Transportation regularly provides transport planning advice for change of use applications across a range of residential, commercial, retail and leisure developments.
Our approach is to identify the highway issues that matter, assess the change from the existing use and provide clear, practical evidence to support the planning application.
Need advice on a change of use application? Contact DW Transportation to discuss the transport and highway requirements for your site.