I do not propose any changes other than the addition of alternative design specs
for a small number of other common foundation types, e.g. raft, raft + ringbeam,
beam-linked piles, etc.
I should have said design guidelines
, rather than design specs
By that I mean that self-builders ought be made aware
within the DoEnv guidelines
of foundation types other than the strip foundations, so that they may choose for
themselves a foundation best suited to their site, house and pocket.
Specialist foundations contractors would usually be aware of the specific arrangements
needed for a given type of house. But it's hard for the ordinary Joe to catch them out
in the act of overdesign.
Then there are the patented foundation systems which come in a limited set of sizes,
each corresponding to a range of loadings. These people won't customise as it would
take away most of their margin.
In commercial practice, I think you'd need a stronger base for your pitch than
simply saying that a structural eng consultation will produce an adequate foundation
for, say, 20% less than the strip foundation estimate for that same house spec.
Because I'd see 10% of that saving going to the struct engineer.
The 10% left is well within the competition margin amongst contractors.
But I wish you well in your efforts for your local house-building clients.
It would be interesting to see a struct engineer's comparative breakdowns of quantities
needed for several foundation systems for an "average" rural house to a modern specification.
We must not forget, of course, that while the structural analysis input to the architecture
courses is not comprehensive, and even if most
architects are not au fait with blending
efficient structural support with good building design, there really are some
adept at this.
But we really have gone way off course with this.
Have your rejoinder and over and out.