Weird sounding construction to me, but probably perfectly normal somewhere =
in the=20
Australian outback~!

A problem I've heard of, specifically with retro-fitted underfloor insulati=
on, is=20
condensation in summer. Air-con indoors now makes floor colder than it used=
 to get=20
without insulation, gaps in insulation allow warm humid outside air to meet=
 cold floor=20
in odd places under the house, air temp drops below dew point, water comes =
out of=20
it. Water gets trapped behind insulation =3D mold, rot, corrosion, etc.

Could be humidity may not be a problem at all where you are. Local=20
builders/architects might advise any tips and tricks with the materials you=
 have in=20
mind.

On 22 Feb 2018 at 14:13, James Cameron wrote:

> G'day,
>=20
> I'm living in a corrugated steel shed, and it's too hot in summer and
> too cold in winter.
>=20
> Walls are double clad zinc plated steel, with a polyester wool
> insulation around steel framing.  Roof is steel plated polystyrene
> insulated panels, 100mm thick.  Windows and doors are aluminium framed
> single glazed.
>=20
> Heat pumps have worked well to moderate, but the IR probes and bare
> feet show the heat is mostly leaking through the floor; with four hour
> lag, apparently normal for the 100mm thickness.
>=20
> The floor is bare concrete, about 200 sq m.  One room has carpet.
>=20
> The concrete was poured onto 0.42 to 0.48mm mean-thickness steel
> roofing [1], which rests on 125mm x 75mm steel bearers, separated by
> about 2.2m.
>=20
> Bearers are welded to steel posts of 75mm x 75mm x 1.2m each resting
> on a 1 sq m concrete foundation block.
>=20
> A photograph underneath is available on request; just don't want it
> archived.  Will reply by private mail.
>=20
> Unimpeded airflow under the shed, which is 1.2m off the ground.  The
> air exchanges heat with the zinc plated steel under the concrete.  The
> profile of the steel has long troughs that act like heat sink fins.
>=20
> We're thinking of adding insulation underneath.  We have a product in
> mind [2].
>=20
> Environmental risks are; high speed wind (~60km/h), leaping male
> kangaroos (about one a year), birds looking for nesting material, and
> a wasp for every size hole.
>=20
> Obligatory PIClist data; we have DS18B20 sensors in several rooms,
> with one for the concrete and one buired 500mm into the ground
> underneath the shed.  Data collected once a minute by PIC 12C509,
> ESP8266, and ATmega328.
>=20
> Listening for your thoughts.  ;-)
>=20
>=20
> References:
>=20
> 1.  KLIP-LOK CLASSIC 700, page 9 of
> http://www.lysaght.com/sites/default/files/LysaghtRoofingWallingInstallat=
ionManualJul2015.pdf
>=20
> 2.  PIRMAX HR Panel 100mm, polyisocyanurate with al foil facing,
> https://reflexinsulation.com.au/products/pirmax-hr-panel/
> http://reflexinsulation.com.au/wp-content/uploads/Reflex-PIRMAX-HR-PANEL-=
Technical-Brochure.pdf
>=20
> --=20
> James Cameron
> http://quozl.netrek.org/
> --=20
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist


--=20
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View/change your membership options at
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