How to insulate shed to stop condensation and dirt?

[Ritar]

I have a skillion roofed shed that gets hot in summer and condensation under the roof in winter and well, dirty inside.

basic shed constructionno insulation under colour bond roof

I have Weathertex board for walls and colourbond roof, north-south orientation in Sydney, high side of roof on western side, low wall on eastern side. 6.6m long x 1.5m wide (yes long and skinny shed). Shed also divided into two sections, one part with the pool equipment and other side with all the usual shed stuff. Dividing wall does not reach the roof totally, about 10cm from the top.

I'd like to insulate the shed to keep heat and cold out and importantly stop the condensation. I'd like to keep the dirt out which I expect mostly comes in from the colour bond roof undulation gaps. 

Any suggestions on easiest solution to fix this? I know the shed is packed (storage and hanging solutions will be dealt with next) but I'm not totally opposed to pulling all the stuff out and doing it properly. 

[MitchellMc]

Hi @Ritar,

You might like to have a read through some of the previous discussions on sealing a shed. This topic comes up quite regularly, and I trust you'll find heaps of helpful information that you can use. 

I suggest starting with some infill strips and pushing them between the roof and your timbers. They'll fill the majority of the gaps. You can fill any other with expanding foam, though it can get messy if you apply too much. Ideally, you should add timber over the area to disguise the foam.

You could add insulation batts and clad over them with plasterboard for the roof.

It's not ideal to completely seal a shed due to a build-up of moisture that leads to tools rusting and mould. I'd suggest a roof vent would be the best way to mitigate this issue.

Please let me know if you have further questions.

Mitchell

[Ritar]

Thanks for the response Mitchell.

I've never heard of infill strips before but they certainly look like something I can use alright.

Yes it seems that batts and plasterboard may be the way to go.

I had considered just using foil boards as an easy option with them resting on top of the battens so I had about 15mm air gap to the roof but I wasn't sure whether I would still get condensation run down from the high roof to low roof side. 

[MitchellMc]

It's tough to prevent all condensation in a shed @Ritar. The condensation is formed from the moisture in the air hitting the underside of the shed roof and reaching its dewpoint. The better you can seal off the underside of the roof to moisture-laden air, the better.

Mitchell