When you can see the joists you definitely need more insulation.
Attic insulation too much.
Too much insulation is not a problem.
To get the best idea designers should conduct specific energy modelling and make key decisions based on balancing performance.
And you may also qualify for a tax credit on the blown in attic insulation cost check with the irs or at energystar gov.
The higher the r value the better the thermal performance of the insulation.
Your attic vents allow warm air to expelled more naturally replacing it with cooler air from outside.
Unless your roofing system has insulation on the roofing deck and is designed without ventilation your furnace should not be heating your attic.
Poor insulation is usually the culprit although if you enter the attic on sunny winter day your attic space can be warmed by the sun more than your furnace.
If a home is over insulated and is too tightly sealed moisture can get trapped inside.
The long term payoff of insulating an attic is impressive too.
Fortunately insulation fixation is a monkey not many people have on their backs.
For diy attic insulation you ve got two choices.
The point of diminishing returns.
It is therefore important to allow the entry of fresh air into your attic to prevent the build up of humidity.
Without proper ventilation a home can build up too much moisture especially in the attic warm air rises which can cause mold problems and overall lower indoor air quality.
There comes a point where too much insulation starts to have a negative effect financially environmentally and in terms of the longevity of your home.
Most homes will keep fairly cool with just six to eight inches of insulation but over time insulation settles so having a little extra doesn t hurt.
Loose fill or batt the common term for blanket insulation.
Twelve inches is often plenty when one or more of these situations is true you re going to need more insulation.
Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live.
Add the right kind of insulation.
The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type.
Once you ve decided which type is best for you examine the material options and prices to home in on the right product.
However there can be a downside if your insulation material is blocking your vents.
If your insulation doesn t measure up and you need more installation can be done as a weekend diy project or you can call a professional installer to handle the job.
So yes it is possible to over insulate your house.