(Property Agents)
© 2026 Treehaus Architects Pte Ltd. All Rights Reserved.
01
Design Consultancy
In a design consultancy model, Treehaus leads the planning and creative direction of the home, while construction is procured separately. Once the design is developed, contractors can price and tender based on the drawings and specifications. This is commonly known as a Design-Bid-Build project delivery model.
02
Key Planning Parameters
Before confirming the design direction, several planning documents should be reviewed as they directly affect the development potential of a landed property:
Road Line Plan (RLP)
Sewerage Information Plan (SIP)
Drainage Interpretation Plan (DIP)
For A&A and reconstruction projects, existing structural and building information may also be required, including soil investigation reports, topographical survey, asbestos survey for buildings built before 1 January 1991, BCA plans, and measured building survey plans.
03
Road Line Plan (RLP)
The Road Line Plan shows whether any part of the land is safeguarded for existing or future road reserve. It indicates information such as the lot boundary, road reserve lines, land required for road reserve, cadastral information, road names, and road category. If the land is affected by road reserve, the owner may not need to act immediately if there is no redevelopment. However, when the land is redeveloped, any building protrusions into the road reserve must be removed. The affected land area may still be included in density or plot ratio calculations for the proposed development.
04
Sewerage Information Plan (SIP)
The Sewerage Information Plan, provided by PUB, shows the location and alignment of public sewers and pumping mains near or within a development site. This is important because sewer lines may create easements, giving PUB access rights for maintenance. These easements may restrict building over or near the sewer line, as PUB requires specific setbacks that can affect layout, buildable area, and redevelopment options.
05
Drainage Interpretation Plan (DIP)
The Drainage Interpretation Plan clarifies the location and extent of public drainage infrastructure within or near the site. It helps identify public drains, drainage reserves, and the Minimum Platform Level (MPL). If a drainage reserve encroaches into the property, it may require setbacks, land to be vested back to the State, or specific platform-level requirements. The drainage reserve may also need to be shown as a separate plot in URA’s Written Permission before being vested or surrendered to the State.
06
Engagement of Professionals
A landed residential project often requires several consultants and specialists beyond the architect. Depending on the project scope, these may include:
Building / land surveyor
Asbestos surveyor
Soil investigation surveyor
Civil & structural engineer
M&E engineer
Quantity surveyor
07
Building / Land Surveyor
A building or land surveyor provides accurate site information required for both design and authority submission. A topographic survey establishes the exact plot boundary, coordinates, and platform levels. For A&A and reconstruction projects, a measured building survey records the existing walls, ceilings, columns, and as-built conditions so the design can be developed accurately.
08
Asbestos Surveyor
For buildings built before 1 January 1991, an asbestos survey may be required to determine whether asbestos is present in the existing construction materials. If asbestos is found, a licensed asbestos removal contractor must be engaged before affected works can proceed.
09
Soil Investigation
A soil investigation report helps determine ground conditions for structural design and foundation planning. In some cases, a soil investigation report from a neighbouring property within 30m may be used, but only with explicit permission from the neighbour who commissioned the survey.
10
Civil & Structural Engineer
The civil & structural engineer designs the structural system and ensures the building is safe, stable, and compliant. Their scope typically includes structural drawings for tender and construction, assessment of contractors’ structural submissions, and authority submissions such as BCA BP01, BP02, demolition permits, and other structural matters involving railings, staircases, skylights, and related elements. During structural works, an RTO or RE may also be required on site. The engineer is appointed directly by the client, while Treehaus acts as lead consultant to coordinate the engineer on the client’s behalf.
11
M&E Engineer
The M&E engineer designs key building services such as lighting, electrical, plumbing, and sanitary systems. For landed homes, their input may also include pump systems for basements and flood-control measures where required.
12
Quantity Surveyor
The quantity surveyor prepares cost estimates from early calculations through to tender and final accounts. A QS can provide preliminary costing before tender, allowing the design team and client to review construction value, manage budget expectations, and carry out value engineering earlier in the process.
13
Consultant Team & Pre-Construction Timeline
The typical consultant team may include the architect as lead consultant, structural engineer, quantity surveyor, M&E engineer, and surveyors. Before construction begins, design usually takes around 3– 4 months, authority submission around 3–4 months, and tender around 2 months. As a broad guide, tender projects may take around 6–8 months from architect engagement to contractor award, while design-and-build projects may take around 5–6 months from engagement of the D&B firm. Topographical, asbestos, and soil surveys may each take around 1.5 months and should be factored into the early programme. Sample Program Link (to notion timeline)
14
Typical Project Timelines
Overall timelines vary depending on project type and approval complexity:
A&A: approximately 8–10 months
Reconstruction: approximately 10–12 months
Rebuild: approximately 12–18 months
Interior works: approximately 4–6 months
Most projects move through schematic design, design development, authority submissions, quotation or tender, award, demolition permit where required, construction, TOP readiness, TOP approval, and move-in. Interior design and interior construction may run in parallel with the main architectural and construction timeline depending on the project scope.