Replies

1. GBA Editor
   Brian Pontolilo|Feb 28, 2020 11:47am|#1

   Hi Wooba Goobaa.

   在无条件或室外空间上方的地板上的最佳案例场景是地板底部的连续刚性绝缘，用于热控制和空气密封。由于您不能这样做，您的热控制选项是用绝缘材料填充托托托架，并使用底板，带有密封剂和/或胶带，尽管也可以包括一层如果您可以提高地板的水平，地板上方的刚性泡沫托梁。除非我缺少某些东西，否则你不需要水控制层，在这种情况下，屋顶，胶合板或OSB底层将给你一个暖侧蒸汽延迟器。本文可能有用：Insulating a Wood-Framed Floor Assembly.

2. 
   Wooba Goobaa|Mar 08, 2020 10:17am|#2

   Thanks Brian. Two sides of this floor assembly are attached to the main structure. We are not foam fans, but this is one area we may use it for air seal. Your thoughts? Thanks

3. 
   Matt F|Mar 08, 2020 12:27pm|#3

   There are a lot of different types of foam. The greenest option is reclaimed foam, check craigslist for dealers. Do you have room above the joists for rigid foam?

   What are your comfort requirements? Floors like this are notoriously cold. If comfort is important, electric radiant in the floor.

1. 
   德克里主克|Mar 08, 2020 01:06pm|#6

   To avoid cold floors you need insulation in the floor but you also need to stop air infiltration. If cold air is entering the room it will sink to the bottom and make the floor cold. This is particularly noticeable in rooms that are unheated below. This is true if the infiltration is anywhere in the room, it doesn't have to be through the floor.

   地板应该有R30绝缘，其余的房间应详细说明尽可能气密。

4. Expert Member
   Malcolm Taylor|Mar 08, 2020 12:58pm|#4

   Wooba Goobaa,

   如果你真的想避免泡沫，你需要更多的深度在地板上以及减少热桥接的方法。我会用斯巴特用2“x4”的地板将现有的托托托架隔热，用贝瓦在它们之间隔热，然后安装子地板。

   If you decide to use some foam, I would insulate the existing floor joists with batts, put down a layer of 3/8" plywood, 1 1/2" of rigid insulation, install the subfloor.

   In terms of how these relate to your control layers: Bulk water intrusion isn't an issue. The assembly can dry to the outside and has a warm side vapour retarder in the subfloor. The subfloor should also be detailed as an air-barrier.

1. 
   德克里主克|Mar 08, 2020 01:01pm|#5

   The joists look undersized, I think 2x6 for what looks like a decent span. The assembly Malcolm describes will also make the floor less bouncy.

1. Expert Member
   Malcolm Taylor|Mar 08, 2020 05:22pm|#7

   DC,

   Good point about the existing joists. I hadn't looked at the floor from that perspective at all. They look undersized.

5. 
   Kevin J|Mar 08, 2020 06:04pm|#8

   I have a closet above a porch like this. Insulation levels are unknown, but I’ll tell you it gets freezing in winter and hot/humid in summer without proper insulation.

6. 
   Wooba Goobaa|Mar 08, 2020 09:20pm|#9

   谢谢你的反馈。澄清和answers to your questions. The joists are indeed undersized and will be sister-ed or replaced to bring the floor level (its a sloped sleeping porch). The bead board ceiling below stays (it is fastened to every other joist), and there is little room to spare atop the joints. The thinking is we use closed cell spray foam to air seal and insulate the band joist connections to the main structure, fill the joist bays with batt or loose insulation, then be sure the subfloor is thoroughly air sealed (per Brians reco).

   You like? No?

1. Expert Member
   Malcolm Taylor|Mar 08, 2020 09:46pm|#10

   Wooba Goobaa,

   这么多取决于你的位置。在许多气候中，只需填充新的更高姐妹托床空间就足够了。在其他人中，特别是随着加倍的托梁额外的热桥接，那个地板将很冷。

7. 
   Wooba Goobaa|Mar 09, 2020 08:01am|#11

   按照OP。项目位于5区5.我们将看到我们可以做些什么来减少托梁的热桥接。

1. 
   德克里主克|Mar 09, 2020 10:49am|#12

   Rather than sistering, if you run pieces of wood of increasing thickness perpendicular to the joists it will both reduce the bridging and stiffen the floor.

1. 
   Wooba Goobaa|Mar 09,09,2020 10:12 PM|#13

   One end of the joists are at the proper height.