Mason
The assistant that answers from evidence, or admits it has none.
Mason answers questions about your own development and the national standards, and shows you exactly what it used. It is not a general chatbot with your data bolted on.
Ask it the way you would ask a colleague
Mason works out where the answer lives — your plot register, your issued documents, or the building regulations — and asks all of them. A question that spans two of those does not come back half answered.
“Which freehold plots have EV charging?”
Your plot register
Answered from the development’s own records, through fixed typed lookups — never from anything a model happens to remember.
“What did the M&E consultant say about the substation?”
Your issued documents
Searched across the revisions your document controller has actually issued. Superseded and withdrawn revisions are never returned.
“What’s the minimum going on a stair?”
The national standards
Building Regulations, Approved Documents, CDM and scheme codes, prepared as citable passages. Staff only.
The rules that keep it honest
It cannot make a number up
Every figure in a reply must appear in the evidence Mason actually retrieved. That is enforced in the code, not requested in a prompt. If a number cannot be evidenced, Mason is asked once to correct itself. If it still cannot, the sentence carrying that number is dropped. If nothing survives, you are shown the evidence instead of an answer — and it is recorded as a partial answer, never as a confident one.
Every answer shows its working
Mason names the document, the paragraph, the page and the edition, and opens that page for you. The citation is checked too: if Mason says 450mm and the page it cited says 400mm, the answer fails before it reaches you.
It tells you when it has nothing
“I’ve got nothing on file about that” is a real answer here. A gap is named rather than quietly skipped, so you know to go and find the document instead of assuming there wasn’t one.
It only ever sees your development
One organisation, one development, re-checked inside the database on every single read. Mason will not quote building regulations to a homebuyer — that is regulated advice under the DMCCA and the New Homes Quality Code, and it is deliberately out of scope.
You set how it speaks, never what it may say
The tone is yours to configure. It can shape warmth and phrasing. It can never change what Mason is allowed to claim, cite, see or do.
Private things stay private
If something is personal rather than work, that is decided before anything is stored, and it never enters project work — not the transcript, not the search, not the audit. Only that person can see or delete it. If Mason is unsure which it was, it asks.
Why the answers can be trusted
Behind Mason sits a separate system that does nothing but read. It takes documents — building regulations, your architect’s drawings, a consultant’s issue — and turns them into sources that can be quoted, with the page and the edition attached. It never answers a question. It only prepares what can be quoted.
Mason asks that system, reads what comes back, and writes the reply using only what it was given. Those two jobs are kept apart on purpose. It is the reason an answer here can be checked rather than trusted.
Common questions
What is Mason?
Mason is the assistant built into BuildSales. It answers questions about a housebuilder’s own development and the national standards, and cites what it used. It is not a general chatbot with product knowledge bolted on.
Where do Mason’s answers come from?
Three places: the development’s own plot register, the developer’s issued documents, and the national standards — Building Regulations, Approved Documents, CDM and scheme codes. A question that spans more than one of those is not answered from only one.
What stops it inventing an answer?
Every number in a reply must appear in the evidence that was actually retrieved, and that is checked in code rather than asked for in a prompt. An answer that fails the check is retried once, then stripped of the unevidenced sentences, and if nothing survives the evidence is shown instead. It is recorded as partial, never as supported.
Can a homebuyer ask Mason about building regulations?
No. Quoting building regulations to a homebuyer is regulated advice under the DMCCA 2024 and the New Homes Quality Code, so it is out of scope by design. The national standards are available to staff only.
Can it see another housebuilder’s data?
No. Mason is scoped to one organisation and one development, and that scope is re-checked inside the database on every single read rather than trusted from the session.
What is Ex Corpus, and is it the same thing as Mason?
They are two separate systems. Ex Corpus is the reader: it turns published documents — standards, drawings, consultant issues — into sources that can be quoted, with the page and edition attached. It never answers a question. Mason is the agent that plans the search, asks Ex Corpus, reads what comes back and writes the reply.
See it answering on your own development.
Send your site plan and accommodation schedule, and we will show you Mason answering questions about your plots and your documents.
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