Small Shed

[MikeG.]

If you have no insulation the breather membrane is simply there to isolate your studs from any moisture ingress from the outside. You will need to counterbatten the studs to provide the airgap. This is the bare minimum to keep your frame properly protected.

 

[Ed Turtle]

If you have no insulation the breather membrane is simply there to isolate your studs from any moisture ingress from the outside. You will need to counterbatten the studs to provide the airgap. This is the bare minimum to keep your frame properly protected.

Ok, i just assumed that counter battening the frame would space the cladding away from the wall, therefore giving me the airgap needed, and therefore negate the need for the membrane, since there should be minimal moisture in the building since there will be no insulation to keep the moisture inside. I assumed wrongly then!

So, i assume i'll be ok to use the non breathable membrane then, same as in the roof?

What about the ridge pole at the rear, it won't be over a stud directly, do i need a double top plate?

Thanks

 

[bhwh]

Presumably driving wind and rain could make its way through cladding towards the frame? So the membrane protects against water ingress?

My shed is similar to yours (ie. basic garden tool store) and I built from outside in:

- featheredge
- counterbattens (battens? Always forget which way around is correct name...!)
- membrane
- osb
- 4x2 frame (no insulation)

Hope I got it right

 

[Ed Turtle]

Far be it for me to say, but i think the osb is meant to go on last, from the outside in. Theres another thread about a 'vapor barrier' (sic) that discusses this in greater detail.

 

[MikeG.]

In an unheated, uninsulated shed, it doesn't much matter where you put the OSB (or ply). However, if you are going to use a membrane, (you don't need to) it makes sense to put the OSB outside the frame with the membrane on top of that, then the counterbattens and cladding.

 

[Ed Turtle]

There we are then, thanks for clarifying

 

[bhwh]

If one later decides to insulate between studs and board out the interior, is there anything that can be done to mitigate the risk of condensation forming within the cavity?

In my case, the framework is constructed from treated timber but still....

Thanks (& sorry to OP for little hijack of the thread)

 

[MikeG.]

If that's even the remotest of possibilities, then put a membrane on the outside and use diagonal bracing on the inside, which you could remove when you insulate and replace with OSB.

 

[bhwh]

Sorry Mike - not sure I explained clearly. My shed is almost finished (using the order of materials I specified above) and although right now I’m happy, I just wondered what you would advise if I wanted to insulate it.

 

[MikeG.]

My advice? .....Not to start from here!

 

[bhwh]

:lol:

I should’ve known I’d get that answer!

 

[Ed Turtle]

Mike, you mentioned earlier that a 4x2 ridge is the bare minimum for a structural ridge. Since I am using a 4x2 (2m long) with 3x2 rafters (600 centres max, closer to 500), does this mean that i dont need a ridge post? So i can support the ridge temporarily as you did in your build, get the gable rafters on then remove the supports? I will be putting a ridge post in of sorts, but its just something to nail the f/e boards on to, so i could do this after putting the ridge etc in place?

Thanks

 

[MikeG.]

Yep, that's fine Ed. The gables hold the ridge up (they're tied at the bottom, so can't spread), and the ridge holds the remainder of the rafters up.

 

[Ed Turtle]

Thanks. Nearly ready to put the ridge up. The walls are done pretty much. Only two problems:
1) Not sure the best way to brace the front section, as its only about 40cm wide (each side) of the door opening. Any ideas?
2) The lintel is screwed to the bottom of the top plate, which is obviously screwed to all the studs. The short studs under the lintel i actually cut a little bit short, so they dont quite reach the lintel, only a few mm though. Will it be ok if the lintel is only attached to the top plate? Could i put some thin wedges of wood in the gap, or perhaps a metal washer? I could get another bit of wood, its just a bit of a pain!

Thanks