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TOPIC: Ventilation

closure strips

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I builit a log home. For the roof I started with 1x8 T&G with 6 mill plastic for vapor barrier. Then I installed 2 x 10 tji for rafters with batt insulation. I then sheeted with 1/2 inch plywood with 30 lb felt with a 1/2 over lap and then the steel. For ventilation i put plugs in the soffit and vented closure strips in the ridge cap. I was told i needed to put closure strips at the bottom and top for moisture and flies. I contend that by keeping it open there is less chance for condensation. I did put the closure strips later because of flies but now i seem to have more flies than before. Did I do the right thing by putting the closure strips in or should have just left them out
Guest User

12/9/2003
You did not say how much insulation you put in as the assembly you describe is venting below the plywood, provided you have enough air space. Dou you have 1" of air space between the plywood and insulation? If so this is OK. Next, did you leave a slot in the plywood at the ridge to vent the space? If so this is OK. Unless you put strapping under the metal roofing which I assume is vertical rib, there should be no reason thatyou require vented eaves closure. It does however add some value in that it will vent the rib channels in the roofing, again depending on profile. Last I would count up your soffit plug vents and using the free area data on them calculate that you do have enough air intake. The code in your situation recommends 1/300 frre air to ceiling area ratio with 50% provide at the eaves. As to the flies, they are adept at hibernating everywhere and I would not worry about it. I have seen many asphalt shingles removed with flies in all the joints. Just ignore it as it is a fact of nature.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/10/2003
You did not say how much insulation you put in as the assembly you describe is venting below the plywood, provided you have enough air space. Dou you have 1" of air space between the plywood and insulation? If so this is OK. Next, did you leave a slot in the plywood at the ridge to vent the space? If so this is OK. Unless you put strapping under the metal roofing which I assume is vertical rib, there should be no reason thatyou require vented eaves closure. It does however add some value in that it will vent the rib channels in the roofing, again depending on profile. Last I would count up your soffit plug vents and using the free area data on them calculate that you do have enough air intake. The code in your situation recommends 1/300 frre air to ceiling area ratio with 50% provide at the eaves. As to the flies, they are adept at hibernating everywhere and I would not worry about it. I have seen many asphalt shingles removed with flies in all the joints. Just ignore it as it is a fact of nature.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/10/2003