Cost-effective option for improving cathedral roof insulation?
Hello all, Hello Martin.
我已经阅读了许多有关如何隔离大教堂天花板的GBA文章和帖子，但我希望有关改善我们特定现有状况的最佳方法提出建议。
我在缅因州沿海地区6a。沿海河附近的大风景点，没有太多庇护所。
我14岁的房子的25 x 25主翼有一个剪刀式的屋顶，基本的沥青木瓦的维修相对良好。
I have soffit vents and a ridge vent, but no soffit baffles. I have two layers of unfaced fiberglass R19. The insulation is not installed against the sheathing, but was instead installed as a blanket, in contact with the back side of the finished ceiling.
To make matters more challenging, the finished ceiling is T&G, applied directly to the trusses — with no base layer to reduce air infiltration.
We’ve now been through two winters here. As you can imagine, the wind blows through the soffit vents, through the fiberglass, through the T&G, etc. The comfort is pretty poor and our minisplit is working a lot harder than it should. I’m ready to spend some money to make at least an incremental improvement.
Any suggestions for the most cost-effective way to upgrade this package? Removing all the T&G isn’t viable at this point. I can get access to the space by deconstructing two skylight wells. The soffit is 12″ wide and can be easily removed.
I’ll attempt to attach a photo taken from the deconstructed skylight well, showing the blanket, truss system, and underside of the roof sheathing.
Thanks for any ideas.
–Bill
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Replies
Bill,
问：“对升级此软件包的最具成本效益的方式有任何建议吗？”
A. Sure. Install drywall on the ceiling.
嗨，马丁。那是相对简单的回复：空气浸润。
Would you also recommend any additional insulation?
谢谢您的帮助。
Bill,
以下是有关舌头和沟渠天花板问题的更多详细信息：
1. In many cases, as long as the ceiling installer didn't use ring-shank nails, this type of ceiling can be disassembled without damaging too many boards. Give it a try, going at the boards very gently and slowly with a flat bar. If the boards pop out without damage, you can reuse them.
2.Once the ceiling boards are temporarily removed, you can install drywall on the ceiling and tape the seams. Pay attention to airtightness at the perimeter of the drywall and penetrations. (An improvement would include installing a continuous layer of rigid foam on the underside of the rafters. Tape the seams of the rigid foam with high-quality tape, and then either install the drywall with long screws through the foam, or install 1x4 strapping, 16 inches on center, on the underside of the rigid foam before drywalling.)
3. Next, reinstall the ceiling boards on the interior side of the drywall air barrier.
4. If the ceiling boards can't be removed without major damage, just install the drywall on the interior side of the ceiling boards -- or improve the R-value of your ceiling assembly by installing a continuous layer of rigid foam, followed by drywall (with or without the 1x4 strapping).
Bill,
问：“您还建议您其他隔热材料吗？”
答：有两种方法可以改善大会的R值：
1.如我的上一篇文章所述，在组件的内侧安装一层刚性泡沫。
2.安装吹几英寸-in cellulose on top of the fiberglass batts. If you go this route, make sure that you don't block the air channels between the soffit vents and the cramped attic.