Outlet air sealing
Location: Chicago Suburbs, Zone 5
I have a question on low voltage wiring for new construction of a residential house.
The wiring would be for network (CAT), Control, Audio, CATV, etc….
I see that there are “open backed boxes/brackets” (Carlon), “closed boxes” (120V type), and “air-sealed” boxes (gasket).
I am conscious of air sealing (techniques) and will also be using a sprayed insulation solution in the exterior walls.
I understand that it is more important to make sure the walls/house is properly air sealed but am trying to comprehend how significant is the air leakage through the outlets? Does it justify the larger cost involved with purchasing a closed or air-sealed box?
Is there advantages or disadvantages of using an open backed bracket/box instead of a closed backed box or air-sealed/gasket box in a wall that will have spayed insulation in it?
If the air is leaking through the jack/wire entry point (into the box) would there be any difference between a closed box vs an air-sealed/gasket box? In both cases the wire entry point would need to be sealed after wires are installed in the box?
Thanks!
Ani
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Replies
Ani,
Every wall needs an air barrier -- but there are several ways to accomplish that requirement.
I have no idea what you mean by "a sprayed insulation solution." Do you mean closed-cell spray polyurethane foam? Open-cell spray polyurethane foam? Blown-in fiberglass? Damp-spray cellulose?
您是否有计划在墙上包括空气屏障？如果是这样，您正在采用什么方法？胶带护套？喷雾泡沫绝缘？气密干墙方法？
Thanks Martin for taking the time to answer my post.
新结构将使用喷涂的玻璃纤维绝缘材料。
The air barrier will be a combination of taped wall sheathing and airtight drywall approach.
I'm investigating a liquid applied membrane to be applied on the outside of the sheathing, but it may be out of my price range.
Ani,
The Airtight Drywall Approach (ADA) requires either special airtight electrical boxes or, at a minimum, close attention to electrical boxes to make sure that the boxes are airtight.
If you are using two air barriers -- an exterior as well as an interior air barrier -- it's up to you to decide whether to follow the usual rules for the ADA, or to relax the rules in light of the fact that you have two air barriers.
Thanks Martin.