monagt,
That's one inference that could be drawn, but there are others that should be drawn.
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#1 Below Cost Building
If the builder is working "below cost" he could have gone bust during the work or carried out substandard or defective work by omission or substitution of cheaper/inferior alternatives.
Alternatively, builders who price very cheaply to get selected from the tender list often moither both the client/employer and architect with extras to bring their work back to profitability.
Finally a builder that is not used to working in a new area may not be aware of hidden costs that may raise his prices - e.g. local suppliers prices vs increased transport costs for materials.
A tender selection from at least three builders would have given you a good idea of the range of prices out there.
One builder may be significantly below the market price to a point where it is clear he is operating below cost or without a sufficient awareness of local cost of doing business.
In such a case your architect would have been quite correct to discuss this with him as well as the likely implications for you, in your role his client and the employer, if that builder is appointed.
your architect not taking a professional overview of the pitfalls of unusually low pricing is not him acting unprofessionally, but acting professionally to ensure that project is costed properly.
In your case, you only went with one builder, a personal acquaintance of yours, and so the benefit of reviewing the spread of tenders did not arise.
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#2 Expected Fee Income
The architect may have formed an idea about the likely fee figure based on percentages for normal costs for that kind of project.
When your builder came in with a relatively low bid he saw any profit in the work go out the window or perhaps saw a loss become evident.
It appears that it wasn't that your architect was trying to increase his fee to an outrageous level - he was trying to get it up to his normal level.
That's why I have posted previously about the use of percentage fees as a basis for an agreed figure - everyone needs to break even on any job.
If people persist in operating on a below cost basis, whether walking into an unknown situation like your builder or working for low fees like your architect - they eventually go bust.
You may wrongly comfort yourself with the thought that this isn't your problem but the defects liability period is a year and retention is seldom enough to pay another builder to snag the work.
Retention is used to induce your appointed builder to come back and snag the work and its a nett cost to him, whereas any newbuilder will charge on a with profit basis, possibly + the 1/19th as well.
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That having been said I'm now hooked on this story.
Did your the builder of long acquaintance raise his price once he realized the cost of doing business where you live?
Did you dismiss your architect for what you saw as his apparent disloyalty and unprofessionalism?
Did you pay your architect revised fees based on an increase in the price?
Was the extension completed to a competent standard?
ONQ
[broken link removed]
All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.