ASI stands for Architect's Supplemental Instruction. It is a written instruction from the architect that clarifies the design or makes a minor change to the work.
The term comes from American contract practice. If you work in Australia, you'll more often see the same idea called an architect's instruction, a site instruction or a superintendent's direction. Understanding the difference matters, because it decides whether you get paid for the change.
What an ASI is.
In the US, an ASI is issued by the architect on standard AIA contract forms to clarify the design intent or make a small change that's not meant to affect the contract sum or the completion date.
A typical ASI might:
- Clarify a detail that's unclear on the drawings
- Change a finish, fixing or minor dimension
- Respond to a question raised by the builder
- Issue a revised sketch or detail
The key assumption is that the change is minor. If it changes cost or time, it should become a change order in the US, or a variation in Australia.
ASI vs RFI.
They often appear together, but they flow in opposite directions:
| RFI | ASI | |
|---|---|---|
| Who issues it | The builder or subcontractor | The architect |
| Purpose | Asks a question about the design | Gives an instruction or clarification |
| Typical trigger | Missing, unclear or conflicting information | An RFI response, a design change or a coordination issue |
| Changes cost or time? | No, it's a question | Not intended to. If it does, it should become a variation |
A common sequence: your team raises an RFI about a conflicting detail, and the architect answers with an instruction and a revised sketch. That instruction is what Americans would call the ASI.
ASI vs variation (change order).
This is where money is won or lost. An instruction described as a "clarification" can still change the work.
In Australia, variations are governed by the contract. Under AS 4000, for example, clause 36 deals with variations directed by the superintendent, and the contract sets out how they are valued. Other contracts have their own variation clauses and notice periods.
So when any instruction arrives, ask three questions:
- Does it change the work?
Compare it with the contract drawings and specification. Extra work, different materials or a changed sequence can all be a change.
- Does it affect cost or time?
Even a small change to a detail can mean rework, new materials or a delay to following trades.
- What does the contract require?
Check who can direct a variation, how it must be notified and by when. Notice periods can be short.
If the answer to the first two is yes, treat it as a potential variation and follow your contract's process. An instruction labelled "no cost" isn't necessarily no cost. This is general information, not legal advice. For a specific contract, get advice from a construction lawyer or contract specialist.
What it's called in Australia.
Australian jobs rarely use the term ASI. Depending on the contract and the project, you'll see:
- Architect's instruction (AI) on architect-administered contracts
- Superintendent's direction on AS 4000 and AS 2124 contracts, where the superintendent administers the contract
- Site instruction (SI) issued on site by the head contractor, consultant or superintendent's representative
- Consultant advice notice or similar on engineer-led projects
The names differ, but the job is the same: a written record of what you've been told to do, by whom and when.
How to manage instructions so you get paid.
Instructions arrive by email, on marked-up drawings, in meeting minutes and verbally on site. The ones that cause disputes are usually the ones nobody logged.
- Register every instruction with its number, date, issuer and the drawings it affects.
- Link it to the evidence: the RFI it answers, the revised drawing, the diary entries and photos.
- Flag potential variations immediately, before the notice period runs out.
- Confirm verbal instructions in writing the same day.
This is the kind of record-keeping the ASI Construct platform handles. Documents files instructions, clarifications and reports by stage with their revision, and the system flags anything that looks like a change for your team to review. For more on why daily records matter, read your site diary is a financial document.
A note on our name.
If you found this page searching for "ASI construction", you may have been looking for us. ASI Construct is an Australian company helping builders and contractors put controlled AI workflows to work, including the instruction and variation tracking described above. You can see the platform here.
Common questions
What does ASI mean in construction?
ASI stands for Architect's Supplemental Instruction: a written instruction from the architect that clarifies the design or makes a minor change to the work. It is a US term. In Australia the equivalent is usually an architect's instruction, a site instruction or a superintendent's direction.
What is the difference between an ASI and an RFI?
An RFI (request for information) is a question from the builder or subcontractor to the design team. An ASI is an instruction from the architect, often issued in response to an RFI.
Is an ASI the same as a change order or variation?
No. An ASI is meant for minor changes that don't affect cost or time. If an instruction does change the cost or programme, it should be handled as a change order (US) or a variation (Australia) under the contract.
Who issues an ASI?
The architect issues an ASI. On Australian contracts administered by a superintendent, such as AS 4000, directions usually come from the superintendent instead.