Wanted - Ideas for 4x3m wooden shed

[inflex]

G'day everyone,

When I used to live in South Africa, we used to be able to obtain small offices/sheds called "Wendy Homes" for not much more than ~$800 AUD, complete with a crew that'd arrive at your property and assemble the whole unit from scratch. The purpose of this building is to be an office for me to work in (Model aircraft store-room and "testing" *ahem* )

Now, back here in outback Australia (North QLD), I've a strong need for a working area of ~4x3m (up to 6x3). I've considered a metal shed and the usual 20' ISO sea containers but the big overwhelming problem is that metal heats up incredibly quickly here.

My ideal setup would be to have a wooden unit set off from the ground by about 300~600mm (600mm would perhaps be better so I could inspect it periodically for termites).

The roof/walls would have to be insulated with foil (not batts) and I'd be running a 12,000btu aircon if required.

Has anyone done something similar? I can't locate any reasonable priced kits in Australia (most are $10k+).

As a parting option, I was considering just translocating one of those caravan park units.

Paul.

[OBBob]

I saw an entire fibro house sell fro $75 on E-Bay ... you had to collect it. They may have secondhand sheds too?

600mm clearance would give better airflow and thus better cooling too I guess.

[inflex]

I saw an entire fibro house sell fro $75 on E-Bay ... you had to collect it. They may have secondhand sheds too?

I'll go take a look. Biggest problem up here is that by the time you ship anything that large you've most likely wasted away any possible savings.

... I wonder if there's a wandering Amish group around here

Paul.

[ian]

have you thought about a double roof on the tin shed or over the shipping container?
it would keep the sun off, thus drasticly reducing the solar heat load.
Lysaught used to make roofing iron with an aluminium coating on the inside to reduce the radiation of heat on the inside. 25 years ago we used it on a shed in Tiboburra (sp?). In summer it was cooler in the shed than in the shade outside.
if you really wanted to go green the second roof could be all solar panels.

ian

[inflex]

Ian,

I have considered having an offset roof on top of the shipping container, extending an additional 2.4m beyond to create an effective pegola as well.

Putting PV cells as the 2nd roof would be a delightful option though somewhat expensive (assuming $900 per 80W panel, roughly 6 panels needed).

Still, one can't help but be entraced by the concept of a nice wooden workshop/shed/office.

Paul.

[Driver]

The roof/walls would have to be insulated with foil (not batts) and I'd be running a 12,000btu aircon if required.

Paul, why are you relying on foil alone? I know it has good reflectivity but its thermal transmittance value is quite low. In other words, it will perform well in terms of radiant heat reflection but it won't do much to reduce conduction or convection. Won't you need something that will slow down the transmission of heat from the metal roof to the inside?

[inflex]

Won't you need something that will slow down the transmission of heat from the metal roof to the inside?

What I'm aiming to do is to actually have a large airflow passing through the walls and the roof by making the walls/roof hollow-spaced like corflute (ever seen the plastic signs they use for election posters?)

Basically the concept is to rely on the airflow to keep the heat away. I've found in the past that beyond a certain point batts simply end up being a heat-storage substance which keeps the house warmer than ambient once the sun has gone down. Probably good for slightly more southern areas (especially in winter) but up here we're suffering 40'C already in the day and summer has barely started

Paul.