2007-11-15 15:16:16 · 6 answers · asked by Carl 6 in Home & Garden ➔ Do It Yourself (DIY)
O.K. people. Heres what rot has to do with insulation. Yes you need good air flow. Yes you need soffit vents and gable vents. But if your going to insulate the roof and not the attic floor you have to be carefull. The insulation cant touch the plywood sheathing of the roof. You need to install "snap vents" on the face of the sheathing to maintain good air flow from top to bottom. These are cheap corrugated looking 2' lengths of thin Styrofoam made for this on purpose.
If you dont put them in the roofing nails points that stick through the sheathing collect frost at night, then melt in the day, then freeze, then melt etc..........Its that traped moisture that rots a roof from the inside. With the snap vents in place the warm moving air of the daytime carries the moisture away every day and keeps your roof dry on the inside. Problem solved.
This is why most of the time you insulate the attic FLOOR instead. Plus you can get a much thicker layer on the floor than you ever will on the roof plane.
2007-11-15 20:15:38 · answer #1 · answered by ctswamp 5 · 2⤊ 1⤋
With all due respect to all, I want to strongly agree with 2 that offered.... WHAT???
First of all, certainly any attic/crawl space should be vented and insulated. Obviously venting should be well protected.
The issue begins however in the substance and stability of the roofing material, and any sealing that has been done to the structure. Unless you have rain/ wind/ storms/ etc. that blow horizontally, or UP from the ground; I suspect you can look in a Million attics (or more) in the USA and not find any issue of leakage or Insulation having anything to do with ROT.
If there is ROT in any attic then your issues go a bit beyond insulation and venting.
Steven Wolf
An added thought. One does not strictly need to insulate a ROOF. One insulates the space between a roof and the upper level of the floor below the space.
2007-11-16 08:10:14 · answer #2 · answered by DIY Doc 7 · 0⤊ 1⤋
I don't know what you think water rot has to do with insulation, that's a roof problem. I would recommend having it blown in professionally. Most off the time it is cheaper or about the same price than just buy rolls of R30 insulation, and alot easier!
2007-11-16 01:32:42 · answer #3 · answered by jdwdrake 1 · 1⤊ 1⤋
Wow you leave a lot of options to be explored. I will assume an existing roof. Just be sure the roof is ventilated from eve to roof. You can install a foil insulation to the atttic space of your home. R30 is about as efficient as you can get for the ceiling with modern technology.
2007-11-15 23:28:54 · answer #4 · answered by Parercut Faint 7 · 1⤊ 2⤋
what has insulation and water rot have to do with it. insulation is protected from rain by a good roof.
2007-11-15 23:21:23 · answer #5 · answered by justagorilla 6 · 1⤊ 4⤋
make sure you have good air flow in you attic. ridge roof vents worl well. or gable vents.
2007-11-15 23:20:16 · answer #6 · answered by Double D 3 · 1⤊ 1⤋