A feasibility study is an early investigation of whether an idea can fit the property, rules, budget, and physical conditions. It is not a permit, a construction estimate, or a full design package. Its value is deciding what to investigate next before committing to a larger fee.
What a feasibility service may include
The scope can be a one-hour consultation, a written memo, a site visit, a concept plan, or a coordinated study. Possible questions include:
- Does zoning allow the proposed footprint, height, use, or parking arrangement?
- Are setbacks, easements, flood exposure, heritage status, or access constraints relevant?
- Can the existing structure plausibly support the change?
- Will the project need a survey, geotechnical report, drainage study, or utility review?
- Is there enough information for a rough cost range?
- What approvals and professional services could follow?
Because these services are not standardized, a meaningful quote names the questions and deliverables. A short feasibility consultation should not be compared with a multi-disciplinary study as though they were the same product.
A sensible sequence
Start with the constraint that could stop the project. For an addition, that may be zoning or lot coverage. For a foundation or slope concern, it may be a structural or geotechnical question. For a flood-exposed property, elevation and local floodplain requirements may come first. For an interior layout change, the existing structure and service capacity may matter more.
The local authority can explain its application path, but it may not design the project or promise approval. Toronto’s pre-application guidance asks applicants to establish requirements and documentation before applying. Seattle’s addition and alteration guidance likewise directs applicants toward project-specific requirements. Those are local examples, not a North American checklist.
How the cost grows
The first conversation is usually less expensive than a study requiring field measurement, concept alternatives, consultant coordination, or a written code and zoning analysis. Cost increases when the property is large, remote, difficult to access, poorly documented, sloped, historically sensitive, or subject to multiple authorities. Revisions and additional options also add time.
There is no reliable universal feasibility-study range. Ask whether the fee is hourly or fixed, whether travel and measurements are included, how many options you receive, and whether the provider will identify items that require later engineering or official confirmation. Treat a rough estimate as decision support, not a bid.
What the study should leave you with
A useful deliverable states what was reviewed, what remains unknown, the assumptions behind any concept or cost discussion, and a recommended next step. It may say “proceed to survey,” “obtain a structural opinion,” “request zoning confirmation,” or “stop before full design.” That conclusion can save money even when it is not a green light.
Do not mistake a feasibility sketch for permit drawings. Do not ask a designer to make a legal determination that belongs to the authority. Do not ask a structural engineer’s limited visit to answer every zoning, drainage, and construction-cost question.
Put a stop-or-proceed value on the unknowns
A feasibility phase is most useful when it ranks unknowns by how much they could change the project. A possible setback variance, a foundation limitation, an unavailable utility connection, or a major drainage constraint may make the current concept unworkable. A finish choice usually does not. Ask the provider to identify which unknowns could stop the project, which could change the design, and which can wait until the next phase.
The scope should also state what evidence will be used. A desk review of a survey and public zoning map is different from measuring the property, opening concealed construction, interviewing the authority, or obtaining a written determination. If the records are incomplete, the provider should say so and identify the smallest next investigation that could change the recommendation.
For a multi-unit conversion, new dwelling, or significant addition, include a question about local growth-related charges among the early constraints. Ask whether the project type may trigger a development charge, impact fee, or system development charge and which authority can confirm the classification. A feasibility consultant can help frame that inquiry, but should not promise an exemption or substitute for the authority’s calculation. The separate charge, payment stage, credits, and conditions are explained in development charges and impact fees.
The point is to identify a potentially material charge early enough to compare alternatives. If the amount depends on unit type, service area, existing legal use, or a future permit date, the study should name that dependency rather than bury it in an unexplained contingency.
Treat feasibility as a sequence of decisions
One project may need several small investigations rather than a single large “feasibility study.” A zoning screen may determine whether a concept is worth measuring. A survey may resolve setbacks and grades. A structural opinion may determine whether the proposed opening is plausible. A utility inquiry may expose a capacity or connection issue. After those gates, an architect may prepare a more developed concept and a contractor may price it.
The provider’s proposal should make these phases visible. Ask for the fee and deliverable at each decision gate, whether later work is optional, and what information would cause the provider to recommend stopping. If a consultant recommends a costly investigation, ask which unresolved decision the test would answer and what the project would do under each possible result.
You can compare the price of two concepts only when they use similar assumptions. One concept may appear cheaper because it omits engineering, permit work, utility changes, site improvements, or a possible growth charge. Use a range for genuinely unknown items and a separate confirmed amount for known fees. Avoid adding every worst-case allowance together as if each were equally likely to occur.
Define the handoff to design
A useful feasibility deliverable should leave a clear record for the next professional. It can identify the concept version, property information reviewed, authority conversations, assumptions, unresolved risks, and recommended next scope. It should also state what it does not establish: final code compliance, permit approval, structural adequacy beyond the contracted opinion, contractor pricing, or eligibility for a local incentive.
Before authorizing full design, review that list with the designer. Confirm that the project brief still matches the option the feasibility work evaluated. If the scope changes, ask which conclusions remain useful and what must be checked again. Paying for a limited early study is most valuable when its assumptions survive into the next stage and do not need to be recreated.
Compare the cost of the project options
Ask the provider to distinguish the cost of studying an option from the likely cost of building it. A feasibility fee may cover a concept and constraint review but not a contractor estimate. If the project has a hard budget, ask whether the professional can test alternatives against that budget and identify which assumptions are too uncertain for a useful estimate.
Compare options using the same scope boundary. For instance, a smaller addition and a larger addition should be compared with the same assumptions about survey, engineering, permit work, utility service, taxes, and project administration. If one option creates an extra dwelling unit or changes site demand, identify possible local charges as a separate unknown rather than treating them as included in the design fee.
The study can also identify timing costs. A project that requires additional approvals, a variance, a seasonal field investigation, or a specialist may take longer before construction can be priced. Ask which steps can happen in parallel and which need a prior answer. Do not treat a preliminary authority response as a guaranteed schedule or approval.
Budget the decision, not just the consultant fee
Before authorizing a study, decide what outcome would make you proceed, revise, or stop. If you would not proceed under any option that exceeds a certain total cost, tell the provider and ask whether the proposed investigation can produce a useful answer within that constraint. If the study only checks zoning, it may leave site, structure, systems, or market pricing unresolved.
Include the fee for the study and a separate reserve for the next investigation it may recommend. A survey, geotechnical report, structural opinion, utility inquiry, or authority application may each be a distinct step. Ask the provider to rank these by how much they could alter the decision, rather than treating all unknowns as equally urgent.
Questions for the proposal
Ask:
- What exact decision will the service help me make?
- What records, measurements, and site observations are included?
- Which assumptions are unverified?
- Will the provider contact the authority or only tell me what to ask?
- Are structural, civil, geotechnical, or survey services included?
- Is the output a memo, sketch, model, schedule, or cost allowance?
- What would trigger a second phase?
The right early investment is the smallest scope that answers the most expensive unknown. Read zoning pre-application review when land-use feasibility is the main question, or preconstruction soft costs when you are assembling the full project budget.