condensation problem on the inside of the roof

[Somnium (Aidan)]

When i woke up the other day to start working on the observatory i noticed that the inside of the roof had formed condensation causing a couple of small pools of water to form. does anyone with building experience know how to stop this from happening. the roof is a suntuff polycarb roof sitting on beams covered in silverwrap.

thanks

[glend (Glen)]

I used Suntuff poly panels for my roof but have had no probems with that sort of condensation. However, my observatory is up off the ground on posts with the pier coming up through the raised floor, the airspace under the floor has weedmat and gravel over the ground. No insulation or sarking just the Suntuff panels over the, roof beams. I have a dehumifiier in there but don't have to use it often. Btw I have a solar powered exhaust fan near the high point of the roof and that runs all the time during the day. I have a little weather station inside that reports on the internal and external temp and humidity. The internal humidity is always at least 10% lower than outside - so ventilate would be my suggestion.

[Somnium (Aidan)]

Originally Posted by glend

I used Suntuff poly panels for my roof but have had no probems with that sort of condensation. However, my observatory is up off the ground on posts with the pier coming up through the raised floor, the airspace under the floor has weedmat and gravel over the ground. No insulation or sarking just the Suntuff panels over the, roof beams. I have a dehumifiier in there but don't have to use it often. Btw I have a solar powered exhaust fan near the high point of the roof and that runs all the time during the day. I have a little weather station inside that reports on the internal and external temp and humidity. The internal humidity is always at least 10% lower than outside - so ventilate would be my suggestion.

doing some research looks like ventilation is key... do you have any images of your set up ?

[glend (Glen)]

Aidan there are photos of my observatory in my build thread on page two of the Obs forum and discussion of heat extraction and dehumidifiers on that page in different threads as well. Good luck.

[astro_nutt]

Hi Aidan.
I used water-based liquid nails to stick on some polystyrene sheets, which I found at the back of an electrical retailer. An inverted 100mm PVC 90 degree elbow with the outside covered flywire, is placed at the roofs highest point, also some ventilation is provided along the bottom of the observatory on the opposite side to allow airflow. Hope this helps.
Cheers!