Metal Shed on a Concrete Base has Condensation is This due to no Damp Proof Course?

by **rhino.fog** » Sat Feb 20, 2016 12:51 pm

I have a metal shed sitting on a concrete base but there is a large amount of condensation inside. The concrete base forms the floor of the shed and the base extends beyond the walls of the shed. The base is flat and solid.

Am I correct in assuming that the reason for the amount of condensation inside is due to the slab having no damp proof course laid under it? If that is correct, what would the options be to remedy the situation.?

I have thought of laying down a damp proof membrane the size of the shed itself and then adding a layer of concrete (or heavy screed) on top as a final surface. I don't want to raise it higher than needed, but again I assume that that layer would need to be reasonably thick not to crack with the DPM under it. Is there a "paint/pour" on solution to plastic sheet that would work as well?
Your feedback would be very much appreciated.

by **Fred c** » Sat Mar 05, 2016 9:46 am

Condensation caused by warm air meeting cold metal. Damp proof membrane will not stop this. Shed needs to be lined with membrane and perhaps insulated and lined with timber. The concrete base should not extend past wall of shed , this could cause floor to be damp.

by **rhino.fog** » Tue Mar 22, 2016 10:24 pm

Shed needs to be lined with membrane and perhaps insulated and lined with timber.

Thank you for the advice.
If I were to insulate, what would be suitable for a metal shed? I haven't seen anything advertised.
Also, would there not be a risk of the condensation forming between the insulation layer and the metal? I am not sure if that would be even worse.

by **welsh brickie** » Thu Mar 24, 2016 7:49 pm

use expanding foam, try www.expandingfoamkits.co.uk

by **rhino.fog** » Fri Mar 25, 2016 10:29 am

Thank you to Fred c and welch brickie for your posts.

Doing some further research myself I came across this site - which had a specific page on metal sheds and condensation.

http://www.secrets-of-shed-building.com/condensation-in-metal-sheds.html

Perhaps this will help someone else.

I can't say that I would not have bought a metal shed, but certainly wiser now and the pros and cons in comparison to a wooden one are not as clear as I first thought.