Table of Contents
Should you insulate attic roof rafters?
Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. Moisture buildup in the attic is a concern because it can condense into water, often causing mold. Good ventilation, from soffit vents and a ridge vent, will stop that.
Can I put insulation on attic ceiling?
To maximize headroom, properly insulate your attic and ventilate the roof, use a combination of dense batt insulation, rigid foam sheeting and air chutes. This means you can have a combined R-value ranging from R-23 to R-31 with only 5-1/2 inches of combined fiberglass and foam insulation.
Can you put insulation between roof rafters?
You can use rigid insulation boards, carefully cut to size, or you can have foam insulation sprayed between the rafters. Whichever approach you use, you will need a specialist professional to insulate your roof – this is not a DIY job.
Should I insulate the underside of my roof?
Air flow helps to stave off the formation of various wood eating molds and mildews. Just packing R-30 insulation against the underside of your roof deck will insulate it but do nothing to dissipate the inevitable moisture that will be trapped within the insulation.
When insulating an attic what should be insulated?
1. In unfinished attic spaces, insulate between and over the floor joists to seal off living spaces below. If the air distribution is in the attic space, then consider insulating the rafters to move the distribution into the conditioned space.
How do you insulate a ceiling with exposed rafters?
If your structure does not need to be well insulated, you can simply sandwich a layer of aluminum foil insulation or rigid foam between your finish ceiling and a layer of sheathing. Place the sheathing layer on top of the insulation and secure it with nails that pass through the insulation into the rafters.
Can you put too much insulation in attic?
It’s possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.
Is it better to insulate attic ceiling or floor?
Because a large volume of indoor heat is lost through the ceiling, the attic floor above is considered the most important area in the house to insulate for winter comfort and efficiency. During summer, attic insulation also protects against excessive heat gain radiating down through the ceiling into rooms below.
Do I need a vapor barrier in my attic?
Plastic vapor barriers should only be installed in vented attics in climates with more than 8,000 heating degree days. All attics — vented or unvented — should have an air barrier (a properly detailed airtight drywall ceiling, for example) regardless of climate.
Should I use spray foam insulation in my attic?
“Open-cell foam can only be put in dark areas such as an attic or behind walls,” Harris said. Closed-cell spray foam is a better choice for keeping subfloor moisture at optimal levels, while open-cell spray foam is a better choice for walls and attics, because it allows homes to “breathe.”Dec 4, 2019.
How much space do you need between roof and insulation?
A minimum 2-inch air space is then provided as an “over-roof” to carry away any moisture that escapes up through joints in the insulation. The ventilation space also helps keep the underside of the over-roof surface cold, thus avoiding snow melting and forming ice dams.
How much insulation do I need between rafters?
Take into consideration the thickness you want to insulate – it is recommended you insulate to at least 100mm to get the optimal performance. Measure the width of your rafters – this is important if you are thinking of insulating below the rafters.
How do you insulate underside of roof?
Open-cell spray polyurethane foam or closed-cell spray polyurethane foam (ccSPF) insulation can be sprayed along the underside of the roof sheathing to provide a conditioned and insulated attic space that can be durable and efficient in all climate zones (see Figure 1).
Should you spray foam your roof?
It really should be called spray foam insulation and air barrier. A properly done spray foam job not only insulates but also greatly reduces the air leakage of a home. If you leave the existing insulation in the attic, it interferes with the foam installation.
How do you insulate attic in hot climate?
There are two main types of insulation used in attics. In a hot climate zone like southern Arizona, for example, we typically recommend blown-in fiberglass and radiant barrier. Blown-in fiberglass insulation provides a dense, effective barrier against heat loss that is also among the greenest insulation options.
Is R 19 insulation Good for attic?
R19 is better than R0. So, if this is the best you can do, go for it. However, most code ask for R21 in Wall, so this is certainly a pretty low value. The reason they ask/recommand for so much in the Ceiling is because it is generally easy to do.
How do you cover exposed rafters?
Install the paneling so that the grooves are parallel to the side walls. Cut short pieces to fit that 12-inch flat part, and then put full panels on the slanted part so the grooves line up. If the rafters are spaced properly, you will be able to nail onto the rafters, even at the edges. It should work well.
