Detached garage with shared roof co/voc infiltration
tupchurch
| Posted in Green Building Techniques on
I am currently involved in the design of several homes. I am recommending a breezeway between the garage and house to mitigate the risks of CO and VOC infiltration. Does a shared roof of some sort still pose a problem requiring some kind of sealing or is the risk insignificant?
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Replies
First thoughts, I hope other people chime in.
If the roof structure is tight to the outdoors but open or leaky from the garage, through the breezeway, to the house, then I expect there's a risk to occupants.
If the roof structure of the breezeway is leaky to the outdoors then I should think any fumes leaving the garage along that path would be dissipated to the outdoors and any that make it into the house would be diluted considerably.
That said, I would detail the garage roof/ceiling and its connection to the breezeway to serve as a 45 mn or 1 hr fire barrier anyway. Doing this would probably eliminate most of the fumes following that path.
tupchurch,
I like breezeways and would commonly include one in a design for architectural reasons, but not simply to mitigate the possibility of air movement between an attached garage and the house. Adequately air sealing the common wall (or roof space) to remove the possibility of contaminants making their way into the house isn't difficult enough to warrant detaching the two.