convert shed into rec-room / granny flat

[wakamole]

I have a large tin shed 6m x 9m x 4.8m high (with 10 deg. pitch) which I was thinking to convert into a granny flat/rec-room.

It is made of 3 bays @ 3m each with 4 150mm x 60mm beams holding it up.

The colorbond is 70mm to the beams held with lateral bracing. I hoped to simply slam the batts in and drywall...now I guess 70mm isn't deep enough.

First I planned to insulate - I'm figuring on r3.5 batts in both walls and ceiling (ceiling/roof will remain cathedral-style) probably held in with mesh or wire until I drywall. I am told I need to put some sort of damp-proofing on before this so glue may not be an option.

Some shed suppliers are offering aircell but at $255 for 30m2 I'm looking at big bickies! I haven't got any quotes on polystyrene (sp?) but will it give a good r value? Cost?

I am handy enough but not experienced and I don't know the rules of the game - I read here that the roof may need to be reinforced before insulating.

Eventually there will be a small bathroom and a kitchenette but for now it will just be a rec room

Any help will be greatly appreciated.

[Feralbilly]

I thought a shed was a Rec Room.

Bill

[inflex]

Wakamole,

While my shed isn't anywhere near as big as yours (6x3x1.8/2.1), I'm also converting it into an office. It'll be interesting to see how you go about getting yours converted.

For myself, I'm using 30mm thick white styrofoam sheeting on the walls with a thin wood veneer on top of that to stop the foam slowly falling apart.

Best of luck!

Paul.

[wakamole]

Well I've been looking at foilboard, styrofoam and silver batts for the roof and probably just cheap old batts bought from the classified ads for the walls.

So far I have determined that supposedly
Silver Batts are excellent and expensive huge r value easy to install - so far I'm leaning this way...
Styrofoam is ok and not too expensive decent r value at 100mm
foilboard is good but lower r value for price
Isoboard and
econodeck have also been mentioned
Aircell too low r value but easy to install

any styrofoam would have to be fire retardent and degassed

any comments appreciated.

[Harry72]

Bah.... build a granny flat dont waste a good shed!

[wakamole]

It is so big it will still serve as a shed! I live in the 'burbs so can't have both - not enough room.

Only one separated room inside - the bathroom/bedroom.

The rest will be open containing the workshop, wife's jewellery studio on one wall, pool table w/ wood table tennis cover etc in the middle on the other wall Kitchenette will double as a wet workspace with removable bench covers - the plan is to make it all very adaptable and stuff granny in there when she visits.

I like that coolgardie safe idea on another thread - free air con - I wonder how well it would work...

[Jim Carroll]

Waka you can do what ever you want in cladding the internal of the shed, When we did it we also put in the reflective foil, this helped in insulation and holds the batts in place while you put the batts in. Put the best insulation you can for the roof and walls.

You will have to put a false ceiling and walls in to support the drywall as the standard spans will be too wide to screw and glue to, not so bad for the walls but the roof will sag.

[wakamole]

Thanks Jim

If I was to use batts or anticon I thought I'd run bracing laterally on the underside of the roof joists so I'd have a big, deep (215mm from ceiling to the colourbond) airgap for maximum insulation and still get the cathedral effect for max airflow and an open feeling in the room so granny doesn't know she's in a shed (after we take the blindfold off).

Polystyrene, isoboard and econodeck are all products that MAY (I don't know) look good enough rendered/painted and will hopefully not sag.

I'm off to research these on Monday.

Silver batts are a bit "sheddy" so they'd have to be covered but they are apparently up to r6!

I suppose I may have to run another upright support as I plan to put in a sliding glass door and windows on one wall.

Any ideas?