Does aerobarrier negate need for airtightness detailing?

[Nickfromwales]

1 hour ago, SBMS said:

So AB after dot and dab? Would have thought having AB at the block layer would be best so pre PB?

Not if really as the results can only be better, the more area covered by dabs, and if the electrics and plumbing 1st fix is done then less trade interference after (risk of them undoing the goodness and then covering it over).

 

AB do say to get all 1st fix in, including MVHR ductwork to outside, but obvs you need to plug up everything connected to the MVHR or the product will push through the ductwork, unit, filters, HEx, condensate and more = MVHR death.

 

Depends who’s on site, who’s going to preserve everything as done, so basically you can decide this yourself.

 

On the project I shared pics of, the PB was off, but the client and trades were well programmed with the ‘not damaging of the AT layers’. 

[SBMS]

20 minutes ago, Nickfromwales said:

Not if really as the results can only be better, the more area covered by dabs, and if the electrics and plumbing 1st fix is done then less trade interference after (risk of them undoing the goodness and then covering it over).

 

AB do say to get all 1st fix in, including MVHR ductwork to outside, but obvs you need to plug up everything connected to the MVHR or the product will push through the ductwork, unit, filters, HEx, condensate and more = MVHR death.

 

Depends who’s on site, who’s going to preserve everything as done, so basically you can decide this yourself.

 

On the project I shared pics of, the PB was off, but the client and trades were well programmed with the ‘not damaging of the AT layers’. 

Understand that first fix needs to be done (but this behind the PB typically).. but if we PB first then AB that puts the AT layer at the PB layer. If there are any cracks etc in plasterboard later then that’s a path that AB will miss? But if the AT layer is behind PB then boarding (with full perimeter dabs) can only increase airtightness? Or am I missing something

[Nickfromwales]

1 minute ago, SBMS said:

Understand that first fix needs to be done (but this behind the PB typically).. but if we PB first then AB that puts the AT layer at the PB layer. If there are any cracks etc in plasterboard later then that’s a path that AB will miss? But if the AT layer is behind PB then boarding (with full perimeter dabs) can only increase airtightness? Or am I missing something

You’re missing the size of the atomised product. Look at the pics, this stuff gets into cracks you can’t even see.

 

It’ll shoot around the back of the boards, down its neck, up its skirt, into nooks and crannies you didn’t even know you had. 
 

It’s a crazy thing to see tbh, but take my word for it, it’ll get into everywhere.

 

Also? Cracks in the plasterboard? 
 

Erm, plaster, 2 coats, and paint, several coats = zero cracks.

[SBMS]

10 minutes ago, Nickfromwales said:

You’re missing the size of the atomised product. Look at the pics, this stuff gets into cracks you can’t even see.

 

It’ll shoot around the back of the boards, down its neck, up its skirt, into nooks and crannies you didn’t even know you had. 
 

It’s a crazy thing to see tbh, but take my word for it, it’ll get into everywhere.

 

Also? Cracks in the plasterboard? 
 

Erm, plaster, 2 coats, and paint, several coats = zero cracks.

Okay fair enough (and you’re right my cracks comment was a bit stupid!)…. But if it does all that does it matter if the plasterboard is in place or not? Still Can’t see the benefit of doing it after boarding rather than before if all first fix is done?

[dpmiller]

doing it after boarding surely risks a "plasterboard tent" scenario?

[SBMS]

36 minutes ago, dpmiller said:

doing it after boarding surely risks a "plasterboard tent" scenario?

It seems Aerobarrier themselves recommend doing after plasterboarding. I guess if the system is designed to find air paths under pressure you want the physical model to be as close to the finished one as possible. Doing dot And dab would create a service cavity that changes the airflow And would potentially create leakage paths which weren’t present pre

PB??

[SteamyTea]

I think, based on this formula, t=(2h/g)^0.5, that better results would happen before plaster boarding.

I also think that the higher up the machine outlet is, the longer the latex will stay suspended in the local atmosphere.