Insulation sits just below the roof s membrane.
Wet attic insulation and drywall.
Drywall is a common component in modern homes used to create a flat facade between rooms.
Insulation loses its r value when wet and is more of a potential liability than anything else in this condition.
For example it is rare to see moisture problems or ice damming on the roof of a detached garage or unheated barn.
Coping with wet insulation.
For diy attic insulation you ve got two choices.
Some insulation types can be saved.
Wetness existing even just for a few days will not only reduce the insulating quality of the insulation but it might not dry soon enough to prevent mold and wood decay from.
Wet insulation in a closed wall cavity will usually not rapidly dry out.
Prolonged wetness will rot out the roof sheathing.
Once you ve decided which type is best for you examine the material options and prices to home in on the right product.
To attach the insulation you can use screws with large washers a special adhesive made for adhering foam board insulation or for smaller pieces you can seal them in with caulk or spray foam.
As its name implies drywall needs to stay dry as moisture results in warping and rot.
However the absorbency of cellulose means destructive mold is still a major factor if it becomes wet.
Glass fiber batt insulation can be dried depending on the level of water damage and amount of water damaged materials surrounding it and the length of time it s been wet polystyrene pellets are another type of insulation that can be dried since they absorb very little water when wet.
Wet walls and insulation will hold moisture for a long time.
Wet insulation is inefficient but more immediately it can be a hidden risk.
Saturated cellulose insulation acts like a wet sponge that continuously transfers moisture to adjacent wooden structure in the attic and to the ceiling drywall below causing mold growth and destructive decay in these materials.
If drywall gets wet replacement is often necessary.
When a roof leak leads to saturated insulation that insulation almost always needs to be replaced.
This means that mold clusters can form inside the wall.
Wet insulation in a wall will migrate to the bottom soaking the wallboard and framing materials.
Wet insulation is bad for your roof your building and its occupants.
Loose fill or batt the common term for blanket insulation.
Foam board insulation is easy to cut with a circular saw with a masonry blade or scored with a utility knife and snapped like you would drywall.
What to do about a wet attic.
When a leak allows water to seep in through.
There are many signs that an attic is wet.
Both can be added to uninsulated attics or layered over existing material.
If the fiberglass within your wall cavity or in your attic becomes wet from a leaky roof or burst pipe it will lose insulating effectiveness until the material dries.
If you can ensure good air sealing and insulation the attic will remain cool and dry as if it were outside.