shed and moisture

[astroturf (Bryan)]

I'm building a 6x5m shed with awning in my backyard in Old Bar

it will have insulation on the roof, the rest will be straight colorbond

as I've had a problem before with mould accumulating on the corrector plate of my LX90,when stored in a double brick home (southern side) I'm a bit wary

Would storing/using the scope in the shed promote mould or would it be better off,
I can store it in its original box with packing for added protection or maybe circulating air might be better

interested in any thoughts
cheers
Bryan

[Sunfish (Ray)]

Any metal structure or scope in humid coastal air will develop condensation with out a vapour barrier and insulation to keep warm moist air off cold metal.

Condensation in a dark box promotes growth of coating fungus, condensation generally promotes growth of all kinds of organic growth, moulds , fungus, lichen and so on. Look in any laundry ceiling without a fan or the south side of any metal structure near the coast.

If you can not insulate your shed metal walls with a vapour barrier , run a dehumidifier or allow it to be flooded with sunlight and air daily you may need to keep your scope in a sealed box with a dessicant . And take it out in the sunlight each day after use.

Originally Posted by astroturf

I'm building a 6x5m shed with awning in my backyard in Old Bar

it will have insulation on the roof, the rest will be straight colorbond

as I've had a problem before with mould accumulating on the corrector plate of my LX90,when stored in a double brick home (southern side) I'm a bit wary

Would storing/using the scope in the shed promote mould or would it be better off,
I can store it in its original box with packing for added protection or maybe circulating air might be better

interested in any thoughts
cheers
Bryan

[mental4astro (Alexander)]

Like Ray said, the inside of any shed will harbour damp. Even a garage will without circulation of air. Circulation of air alone is not enough. It very much depends on the construction & design of the shed/structure, even on how things are stored inside the structure as air may not move around it enough - how many camera lenses have been lost by being stored in a wardrobe...

A box is no protection as it too will attract mousture. If anything keeping your scope in its box for long periods of time is a bad idea as the scope itself is not experiencing circulation of air around it.

If the shed will be sealed, you will need not just circulation of air but also some way of extracting damp that will still build up, something like a dehumidifier. Air con does the two jobs in one with the added bonus of keeping your scope cool, but this is not a cheap option.

Alex.

[mental4astro (Alexander)]

Oh, and these air circulation and dehumidifier options can also be solar powered.

A dehumidifier will need draining. Most small units come with a small drainage tank, but some do also have a drainage hose option. This hose can be put through the wall of the shed to drain outside, saving you having to regularly need to empty the tank.

[taminga16 (Greg)]

Bryan,
Install several floor height and roof vents.

[glend (Glen)]

Bryan, forget using colourbond, you will just be creating a dew collector. I live on the water, with a colourond garden shed, I know what happens.
When I built my observatory I used two big principles:
It had to be off the ground on stumps so that air could circulate underneath, and it would be built of standard stud wall construction with marine ply exterior panels. The roll off roof, is also stud framed with ply sides and top is corrugated poly roofing, with insulation on the underside. This observatory has been in use for five and a half years with no damp problems at all.
The pier footing was poured before construction, and it rises through the observatory floor, without touching the flooring.
Stumps are bedded in concrete, then a standard heavy timber deck frame was built and topped with ply tongue and groove flooring. The walls were built flat on the deck then raised into position, and corner braced. All standard house construction process.
It has survived sustained winds of 100kmph during east coast low storms, and it does not leak. The internal side of the walls require no insulation, they do not sweat like metal would.
I did have a small solar powered exhaust fan for the first few years but after it failed I just left the ridge vent, it is fine.
So I am saying, don't just rush to colourbond, it is not the best way to do it in our environment.

[astroturf (Bryan)]

thanks everyone for your valuable info and opinions


the colorbond shed is ordered and going ahead so I cant change that

it will be great for my woodworking hobby and other general tinkering

it will be ventilated to get rid of condensation, however I think after reading your replies the scope will go back to its spot in a spare bedroom where damp doesn't seem to be present ,I'd rather not have that mould problem again

the dew certainly is a lot heavier here, I'll have to make sure that dew strap/heater is working, other than that the night sky visibility is excellent after living in Sydney

cheers
Bryan