Why Does Outdoor Space Need to Be Designed in Stages?

Designing outdoor space in stages – from concept design to construction working documents – helps resolve conflicts before they reach construction procurement or the construction site.

The Need for Landscape Design

Landscape architecture brings the building, accessibility, the road network and parking, grading, stormwater management, utility networks and outdoor lighting, waste management, site furniture and vegetation together into one coherent site plan. If these aspects are addressed separately or too late in the process, conflicts may arise, and resolving them can affect the budget, schedule and quality of the final result.

Landscape has a direct impact on how a development is perceived and used. Well-designed accessibility and parking, recreational areas and playgrounds, views opened or screened by vegetation, stormwater management, outdoor lighting and outdoor furniture are not merely finishing touches. They form an integral part of the construction design documents and influence both the user experience and the positioning of the property on the market. Landscape design can therefore be regarded as a value-creating component of the development.

A well-designed outdoor space helps differentiate a development from its competitors, shortens the sales period and strengthens the sales proposition because the completed environment does not fall short of the quality promised in visualisations and marketing.

The Logic of the Design Phases

According to EVS 932:2017, design generally progresses from broader principles towards increasing levels of detail. The concept design establishes the key principles; the preliminary design verifies the suitability of the solution; the detailed design specifies the information required for construction procurement and cost estimation; and the construction working documents provide the level of detail required for construction. If one of these design phases is effectively omitted, the unresolved issues do not disappear. They are simply transferred to the next phase and often emerge at a point when correcting them is more expensive and more critical in terms of time.

The Design Brief Determines Whether the Design Process Moves in the Right Direction

Before design begins, the desired outcome must be defined. The design brief should describe not only the location of the site and the required scope of work, but also the commercial objectives of the development, the target group, the desired image and concept, the required quality level, budget constraints, maintenance principles and the anticipated schedule.

See also our blog post What is a design brief and how to write it?

If the baseline information is incomplete, some design decisions have to be made on the basis of the designer’s best assumptions. This can result in numerous alternative versions and unnecessary additional work. For the developer, this creates a risk that the proposed landscape design will need to be redesigned at a later stage, the building permit application process will be prolonged, the basis for construction procurement will remain insufficiently precise, or additional costs will arise during construction.

Concept Design: Testing the Concept and Investment Logic

Under EVS 932:2017, the concept design is not a design phase of the construction design documents in the same way as the preliminary design, detailed design and construction working documents. It is a conceptual document based on the design brief and is used to assess whether the proposed outdoor space supports the development concept, whether the spatial and commercial potential of the site has been used appropriately, and whether the solution complies with local regulations. During the concept design phase, the overall principles of the landscape are established: accessibility, walking paths, the logic of entrances and connections, boundaries between public and private space, principles governing parking and the pedestrian experience, the role of vegetation, views, functions and the overall character of the development.

For the property developer, the value of the concept design lies in the ability to make the most influential decisions while the cost of making changes is still relatively low. If the concept design does not support the overall concept of the development or the expectations of the target group, or if there is a mismatch with the anticipated construction cost, the design can still be adjusted at this stage before it becomes increasingly fixed in subsequent design phases.

Preliminary Design: An Approvable and Fundamentally Suitable Solution

During the preliminary design phase, the direction selected in the concept design is developed to a level that allows its fundamental suitability to be assessed against the design brief, spatial plans, design requirements, surveys, technical conditions and legislation. The objective is not to resolve every construction detail, but to select a technical solution that can be developed further and whose overall principles are acceptable.

For the property developer, the preliminary design is primarily connected with obtaining the building permit, securing the necessary approvals and verifying that the solution remains within budget. At this stage, it becomes clear whether the outdoor space works together with the building, roads, parking, access points, stormwater management, the location of utility networks and vegetation. Where conflicts arise, they can still be resolved during the design process rather than during construction procurement or construction itself.

It is important to understand that obtaining a building permit does not mean that the design process is complete. The preliminary design establishes the direction and provides the scope required for the building permit application, but it is not the basis for carrying out construction work. If construction proceeds solely on the basis of the preliminary design, there is greater room for interpretation, less certainty over costs and a higher risk of additional work.

Detailed Design: Construction Procurement and Cost Control

The purpose of the detailed design is to develop the selected solution to a level of detail that enables construction costs to be determined, construction procurement to be organised and comparable construction quotations to be obtained. In landscape design, this means specifying surfacing and paving, structures, materials, the bill of materials and bill of quantities, quality requirements for plant material, quality requirements for outdoor furniture, construction details, and the relationships between grading, utility networks, lighting and other parts of the project, as well as requirements for construction quality.

For the property developer, the detailed design is one of the most important tools for mitigating cost risk. If the design remains too general, each contractor will price it differently. One tenderer may assume cheaper materials, another may exclude some of the work from the quotation, while a third may include a substantial contingency. The result is not a genuine comparison of prices but only an apparent comparability between quotations.

A properly prepared detailed design helps prevent a construction quotation that initially appears inexpensive from becoming considerably more expensive later through additional work. It also helps maintain the development’s quality promise, because requirements for materials, products and solutions are defined before procurement rather than being negotiated between the parties on site during construction supervision by designer.

Construction Working Documents: The Basis for Construction and Construction Supervision by Owner

The construction working documents constitute the most detailed design phase. Their purpose is to provide the specifications required for construction work and construction supervision by owner. The solutions are defined in sufficient detail so that the contractor does not have to interpret critical construction details, dimensions, levels, installation methods, products or material compatibility independently on site.

The role of construction working documents in landscape design is particularly important where different systems meet: paving, edges and vegetation; stormwater management and grading; trees and utility networks; site furniture and trees; as well as lighting, movement routes and accessibility.

For the property developer, construction working documents reduce ambiguity on the construction site. The less that is left to the contractor’s interpretation, the lower the risk that the completed result will fail to correspond to the development’s intended image, the promises made in marketing materials or its long-term functional requirements. Construction working documents also support effective construction supervision by owner, because the completed work can be checked against the designed solution.

Why Is Omitting a Design Phase Not Really a Saving?

Reducing the scope of design may appear to create savings in the design budget, but from the perspective of the development’s total cost it may simply shift risk to a later and more expensive phase. If a design documentation has not been developed in sufficient detail, problems may not become apparent until construction procurement or work on site.

Changes made during construction have a greater impact. The sequence of work, orders, quantities, materials and contracts may need to be changed; construction may need to be suspended; or already completed structures may even need to be demolished. Additional approvals, explanations from the designer or additional design work may also become necessary. A conflict identified during the design process is therefore generally more manageable and less expensive to resolve than the same conflict discovered during construction.

From the property developer’s perspective, the risk is not limited to higher construction costs. It also includes delays to project completion, weakened sales arguments and damage to the development’s image, dissatisfaction among users, increased maintenance requirements and a situation in which the outdoor space fails to support the value of the property as effectively as it could.

What Should Be Defined When Commissioning Landscape Architecture Services?

Design Brief

Because the value of a development is also influenced by its outdoor space, a list of functions alone is not sufficient for the design brief. The brief should also describe the spatial experience that is intended to be created: how people approach the building, where they stop, what they see and how they move through the space. This means that views, recreational areas and playgrounds, and accessibility also need to be addressed. This helps avoid a situation in which the outdoor space is technically correct but fails to support the identity of the development or increase its sales value. The design brief should define: what kind of identity the outdoor space should create for the development; which outdoor-space functions are required for different user groups; how accessibility is to be resolved, including access on foot, by bicycle and by car, as well as accessibility for people with mobility, visual and hearing impairments; how stormwater is to be managed, whether through on-site infiltration or the stormwater drainage network; what type of site furniture is preferred, whether custom-designed or catalogue products such as benches, barriers, bicycle racks, litter bins and lighting fixtures; and how the outdoor space should support the building concept, user experience and the market positioning of the development.

Studies Preceding Construction Projects

Which baseline information, studies preceding construction projects and technical conditions are already available, and which still need to be obtained? Who is responsible for obtaining them? Read for more from our blog Woody plants survey: why, for whom, and when?

Integrated Landscape Design vs Urban Greenery Design

Which parts of the landscape design are to be resolved within the landscape design, and which belong to other parts of the construction design documents?

Construction Cost Estimation

At which design phase should construction cost estimation be carried out, and whose scope of work does it form part of?

Conclusion

The phases of landscape design should be regarded as tools for managing both the value and the risks of a development. The concept design helps test the concept and the spatial potential of the development. The preliminary design helps establish a fundamentally suitable solution for which a building permit can be applied. The detailed design provides the basis for determining costs and organising construction procurement. The construction working documents provide the level of detail required for construction.

If any of these steps is effectively omitted, genuine savings are rarely achieved. Instead, there is an increased risk that issues left unresolved in the omitted phases will reach construction procurement or the construction site, where their impact on the budget, construction schedule and quality is considerably greater.

It is therefore in the property developer’s interest to commission the outdoor-space solution at a level of detail that corresponds to the objectives of the development and the actual complexity of construction. A thoroughly developed outdoor-space solution is not merely a higher-quality design. It is a more controllable investment, a stronger sales proposition and a lower-risk basis for both construction and long-term use.