Does Isover's spacer sleeve provide an air gap (facade board)?

[smurfen72]

I'm not keeping up, is there research that contradicts what you presented? 8-12 mm, which is quite common, is the entire gap that forms between the paper and the panel with traditional insulation with, for example, Isover's solution, the gap becomes as thick as the battens, presumably around 28-34 mm, but the vertical gap becomes smaller as only the gap within or between the boards is used. I have no idea how large a gap is required to create a pressure equalizing chamber, but I guess a very small gap is needed to equalize the pressure or how large a gap is required?

 

[KnockOnWood]

What HUL writes about pressure-equalized chambers, etc., is just nonsense, and it's a bit of a shame, because in principle HUL is right!

The exterior panel gets wet in the rain, some water penetrates behind the panel, and the moisture needs to be ventilated away so it doesn't stay in the insulation and wood and cause mold.

So an air gap is needed, and it should naturally be open at the top and bottom, so there can be a little air exchange through convection, which ventilates away the moisture.
It's elementary physics!

Solving this with an extra centimeter-thick batten behind the nail battens when you have vertical paneling seems like a cheap price to keep the outer walls healthy and dry!

 

[smurfen72]

Normally, I think the panel manages well without an air gap as it is so thin, about 22 mm, so it should dry well even if it only dries outward, but the insulation is likely to get some moisture in it. A regular 45*95 freshly sawn piece dries in a few weeks if it is lying freely, and the panel should do the same as it only dries in one direction.

 

[Nyfniken]

Yes, it would have worked. If the house hadn't been painted with something akin to a plastic bag.

 

[smurfen72]

Choosing a color to paint with that's like a plastic bag must be exceptionally foolish, regardless of whether you have an air gap or not.

 

[Nyfniken]

It depends on whether you like to paint or not.

 

[smurfen72]

I don't understand what it has to do with it regardless of whether you like to paint or not, one should choose a color that can't be likened to a plastic bag to paint with something like that whatever it is will probably ruin the house more than protect it.

 

[hul]

I normally think the panel manages well without an air gap as it is so thin, about 22 mm, so it will dry nicely even if it only dries outward. However, insulation is likely to absorb some moisture. A regular 45*95 freshly sawn piece dries in a few weeks if it lies freely, and the panel should also dry as it only dries in one direction.

Yes, but with your reasoning, an air gap is unnecessary. But now there is an air gap for entirely different reasons than those you mention.

 

[smurfen72]

What reasons did you think there were for not getting moisture in the insulation? I asked a question earlier about how large a gap is needed, but you avoid answering questions why do you do that?

 

[hul]

The function of the air gap is to be a part of a two-stage sealing function. It separates the rain sealing from the wind sealing with a pressure-equalizing layer.

Therefore, the moisture that enters the air gap will be ventilated away by air circulation, and to achieve this, a sufficiently wide air gap is required where air can travel freely and is open at the top and bottom.

This leads to a pressure difference across the façade between dry areas, thus eliminating the risk of moist air being pressed into the façade and condensing, or alternatively, water being pressed into the façade.

 

[smurfen72]

That is, the same as I wrote about not getting moisture in the insulation, even though you elaborated a bit more. You still haven't answered how big the air gap needs to be, why are you avoiding answering the question?

 

[hul]

In other words, the same as I wrote about not getting moisture in the insulation, but you elaborated a bit more. You still haven't answered how big an air gap is necessary, why are you avoiding answering the question?

I can't answer with an exact number, and that's not my intention either. Rather, it requires an air gap, and having only horizontal battens and panels does not fulfill an adequate air space. Many have advocated that horizontal is enough, but then moisture cannot be ventilated away, which leads to a damp "air gap" and thus the two-stage sealing serves no function and damp air will be pushed into the facade.

But several of the reports showed that there was a significant difference in drying time if you increased from a few mm to up to 15-20mm.

 

[smurfen72]

But now you answered at least, which is a prerequisite for some type of discussion. The question is whether it makes any difference with a longer drying time. A traditional air gap, say 12 mm, where paper and insulation often bulge out and are closer than that to the panel seems to work well as far as I know, but the Isover type with about a 30 mm gap + vertical ventilation via grooves in the panel would not work sounds unreasonable to me.

 

[hul]

But now you answered at least, which is a prerequisite for some type of discussion. The question is if it matters with a longer drying time. A traditional air gap, say 12 mm, where paper and insulation often bulge out and lie closer than that to the panel seems to work well as far as I know, but the Isover type with about a 30 mm gap + vertical ventilation through grooves in the panel wouldn't work sounds unreasonable to me.

Now we're talking differently or the same, depending on how you see it.

The air gap that several have advocated here, which Isover included in some installation instructions, consisted of horizontal battens and panels placed directly on them. So 0 mm air gap where the panel is against the nailing battens. That was what I was against.

Where are you getting some 30mm plus vertical battens from?
In that case, it's great, but that wasn't what was discussed in the thread, and several advocated for.

 

[smurfen72]

There will be a 30 mm gap between the insulation and the panel, but the vertical ventilation between the compartments occurs through slots or gaps between the panels. A short reduction on a pipe within plumbing or ventilation doesn't significantly restrict the flow, and I assume it will be similar here as well, that the airflow will be greater than what the small slots would provide if it were only ventilated through them since the gap is so large over most of the wall.