How to stop condensation on garage Colorbond ceiling?

[rebelliouskiwi]

I live near the Blue Mountains in NSW & the recent frosts have been causing a lot of condensation on the inside of my garage, where I have cardboard boxes. Temporarily thrown tarp over the storage, but looking for a more permanent way to prevent drips inside. Can I gyprock and insulate to prevent this? I know I can paint a textured paint but thinking that may work out more expensive an more work? Internal measurements of ceiling are 3240mm x 5320mm. 565mm gaps between each ceiling beam.  What products would I need for this? It's an old garage, so don't want the most premium products at all. just something to get the job done on a cheap budget and keep my boxes dry before next winter.

 

[JacobZ]

Hi @rebelliouskiwi,

The condensation is forming because the warm air underneath the roof sheets is hitting the cold metal, and the moisture in the air is condensing.

To address this issue, your best option is to install insulation and a ceiling lining. Insulation helps regulate the temperature inside the garage, reducing the difference between indoor air and the cold metal roof. This, in turn, prevents condensation from forming. 

You can install ceiling batts between the ceiling framing, which would be supported by insulation strapping held in place with staples. Insulation batts are produced in a variety of thicknesses and two main widths, 430mm and 580mm. You would be best using 580mm batts that are a suitable thickness for your framing.

Pair these with a basic ceiling lining like Villaboard, which is moisture-resistant and will be better for garage environments.

Another option is to install Foilboard between the framing, using the Foilboard Insulation Flexi-fast Fasteners and following the Cathedral Roof Installation Guide.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[JacobZ]

Hi @rebelliouskiwi,

You might also like to check out the following discussions for some examples of similar projects with similar discussions -

• How to insulate a metal roof?
   
• How to insulate a patio roof?
   
• How to stop condensation on patio roof?

Let me know if you have any further questions.

Jacob