How to ventilate panel on gable

[fatman]

Hello,

If this has been addressed before and I can't find the information, I apologize. I have the following problem that I can't quite figure out. I know that there should be an air gap between insulation and paneling on the wall (I have horizontal paneling).

My problem is that I don't understand how to ventilate the walls on the gables?

Many houses that I've looked at have completely sealed gables, there is an air gap between panel/insulation but no ventilation at the roof.

I might have completely misunderstood, could it be that having an air gap for the walls is enough, and there is no need for an "entry/exit" for this air gap?

Grateful for help
/

 

[Mats]

A wall is not completely sealed so that ventilation is probably sufficient.
Have actually never thought about it.

 

[Crebel]

Had the same question in an earlier link, check at the end of this:
http://www.byggahus.se/forum/fasad/146579-staende-panel-med-luftspalt-och-musskydd.html

 

[fatman]

Have also considered this solution, but what is strange is that I have seen many new houses that completely lack this ventilation at the gables. (Also missing it at the eaves but there I assume they have used mold stopper instead.)

 

[Crebel]

Yes, I have noticed the same thing, I have not yet decided what to do myself...

 

[zsimpey]

it may be because it is kalloft and the gables are ventilated towards the loft instead? that's how my house looks. but otherwise, do they run all the way up into the cladding or is there underspiking?

 

[Crebel]

Just checked my brother's house today, the main building from the 80s had ventilated soffits but for the entirely new living room extension with open ceiling all the way up, there was no ventilation at the top edge of the facade. And no cold attic to ventilate against either...

 

[zsimpey]

The gable is open for circulation on 3 sides (bottom + short wall ventilation). But that should provide fairly reduced ventilation for the upper part of the gable... hmmm I'm trying to find a solution.

 

[Crebel]

One should also note that there is a certain ambivalence regarding the related issue of vertical air gap when dealing with a standing facade panel.

If you do not use two layers of battens (one standing, then one horizontal) or at least provide some distance beneath a horizontal batten, you will not get any vertical air gap at all, making an opening at the top pointless.

Many seem to think it's acceptable to skip the vertical air gap and only use horizontal battens; on a more official building site, I read that it was okay "if the location isn't exposed," whatever that means. Which, as mentioned, would also mean the air opening at the top would be negotiable.

Is it possibly one of those questions where ambitious DIY builders are more nitpicky than the professionals?

 

[fatman]

I see that there are more people than just me who are a bit puzzled about how (or if it's needed) to do it.
The thing is, I don't have a cold attic/loft but have insulated up to the ridge.

We have used the under-batten method on the gables/long sides http://www.traguiden.se/TGtemplates/popup2spalt.aspx?id=4557&contextPage=5947
On the long sides, we chose to install mold stop, but on the gable, we will probably not have any ventilation at all up by the roof. Then we just have to hope that this works.

 

[Danne031]

One should also note that there is a certain ambivalence regarding the related question of vertical airspace when using standing facade paneling.

If you do not lay two layers of battens (standing, then horizontal) or at least a certain distance under a horizontal batten, you will have no vertical airspace at all, and then it is pointless to have an opening at the top.

Many seem to think it's okay to skip the vertical airspace and just go with horizontal battens; on some more official construction site, I read that it was okay "if the location is not exposed," whatever that means. Which, as said, would also mean that the air opening at the top would be negotiable.

Is it possibly one of those questions where ambitious DIY enthusiasts are more meticulous than the professionals?

I think it was at Beijer I found that they said with overlapping paneling with overlaps larger than 70mm, the ventilation is sufficient with just one batten.
The question is how, for example, should I do at my place... I have started setting 120/120 standing. On the long sides, there are no problems because above the paneling, I have 45mm air to the sheathing (cold attic), I have no fascia, just visible sheathing.
But on the gables, how should I do there? I lay a 95 batten against the sheathing, then I put as a cover a 95 that follows the roof angle and is painted with ridge color. Then it will be airtight.

Though, as mats_o says, a wall is never completely tight, maybe especially not if you're setting 120/120 like I am...

 

[zsimpey]

Wide boards tend to twist and shrink/swell a bit more, and then hopefully become a little loose. Interesting subject.

 

[Crebel]

Standing panel with battens does not indeed have the same problem with a vertical air gap as facade standing panel.

If you don't want to use under-nailing, can't you set the 95 along the roof angle on top of the regular battens (which you don't allow to reach all the way to the roof angle, but make them just over a centimeter shorter)?