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General => General Forum => Topic started by: Arky217 on November 03, 2015, 11:01:11 AM

Title: Condensation question ?
Post by: Arky217 on November 03, 2015, 11:01:11 AM
Does anyone have a garage or storage building that has metal siding
directly over the studs ?

If so, do you ever get condensation on the inside of the metal siding ?

I'm building a small garage. I will have plywood and metal on the roof.
But on the walls, I'm considering just diagonal braces on the inside
and metal directly over the studs.

The garage will not be insulated or heated/cooled; just a place to
park one vehicle and a small workshop area.

On this foggy morning, I noticed that I had condensation on the
inner surfaces of not only the ceiling but also the walls of my carport.

Now I'm wondering if the inside walls of the garage will do the
same even though, unlike the carport, it will be closed in.

What think ye ?

(just remembered that I previously had an uninsulated, unheated garage with 2 uninsulated steel garage doors and I never had condensation on the garage doors)

(if it matters, the slab for the garage has poly under it and sealer on top)

Arky
Title: Re: Condensation question ?
Post by: Redoverfarm on November 03, 2015, 12:01:00 PM
One of the biggest draw backs of metal.  They all will sweat regardless of whether it is on the roof or walls.  Not so much on the wall as the roof.  Only way around is to insulate to keep the meeting of cold & hot at bay.  Generally that is why most metal buildings is spray foamed or a insulation board is applied between the structural and the metal. 
Title: Re: Condensation question ?
Post by: Arky217 on November 03, 2015, 12:48:22 PM
Another thought, what if I just covered the studs with Tyvek ?
That would cost about $112.

Or I could just sheath with osb under the metal, but then I
probably should cover the osb with tyvek any way.

Osb would be about $215 and $112 for the Tyvek.

Think Tyvek alone would be ok ?

Would I still get any wall condensation between the Tyvek and metal,
and if so, would that be a problem, or would it just drain down to the bottom ?
Title: Re: Condensation question ?
Post by: NathanS on November 04, 2015, 09:01:36 AM
IMO you don't need to put OSB under the metal because the condensation will still happen, and OSB does not respond well to water..

I think just triangular bracing + metal siding is just fine.

On the roof you want felt paper or building paper between the plywood or osb and the metal.

With no insulation the building will be very breathable so any condensation will dry out quickly so you don't have to worry about rot.
Title: Re: Condensation question ?
Post by: JRR on November 04, 2015, 12:23:24 PM
I think I would avoid sheathing on the roof ... just go with rafters and purlins (sp?).  If you make the construction "open" enough, whats a little condensation gonna hurt?  Its probably not going to be an all-time event, just when temperatures and humidity are "just so".   But when the metal is cool and hot vapors are coming off of the car, and you, ... condensation is very likely if the cool metal is in the path of air flow.
Title: Re: Condensation question ?
Post by: akwoodchuck on November 04, 2015, 01:02:04 PM
Quote from: Arky217 on November 03, 2015, 12:48:22 PM

Osb would be about $215 and $112 for the Tyvek.

Sounds like money well spent....that way, if you or a later owner do decide to insulate/heat, it's good to go.
Title: Re: Condensation question ?
Post by: MountainDon on November 04, 2015, 02:13:45 PM
A roof or a wall that is sheeted with osb produces a much more rigid structure than a few diagonal braces.

I personally dislike ceiling / roof drips so I would and I did sheath the roof of our sheds with osb before applying roofing felt and then ribbed metal roofing. I sheeted 2 walls with OSB, building felt and the same ribbed metal. The othyer metal was installed over horizontal wall purlins. It is very rigid and I have never seen a drop of water inside; neither rain or condensation. And the building is very rigid.



It never surprises me to see how many times I have changed the purpose of something. Fully sheathed walls would make a future change to heating or whatever simpler.