Just follow the steps.


A bag of Greenfiber insulation covers approximately 70 square feet when installed at the recommended depth of 10 inches. SANCTUARY® by Greenfiber loose-fill blow-in insulation has an R-value of 3.7 per inch, which is higher than other types of insulation, such as fiberglass batting or mineral wool. This means it can provide more effective thermal protection in colder climates. 

R-value is a measure of insulation’s efficiency. The higher the R-value, the better the thermal performance of the insulation in locking heat in and keeping heat out, depending on the season. Your recommended R-value will depend on the climate in which you live.

Also, your energy savings from insulation will depend on the climate, the type and size of the house, the amount of insulation already in your house, and your fuel use patterns and family size. If you buy too much insulation, it will cost you more than what you will save in fuel. To get the marked R-value, it is essential that this insulation is installed properly. Find an expert Trusted Installer near you for a contractor or builder who can install your SANCTUARY® insulation correctly and efficiently. 

Greenfiber’s SANCTUARY® insulation has an R-value per inch of 3.7, which is higher than other types of insulation, such as fiberglass batting or mineral wool. This means it can provide more effective thermal protection in colder climates. 

For attics, you should aim for an R-value between 38 and 49, depending on your specific needs and climate zone. To achieve an R-value of 38 to 49 in your attic, you should aim to install 11 to 14 inches of blow-in cellulose insulation. Note that this range is dependent on whether or not you have existing insulation in your home, and that SANCTUARY® blow-in insulation by Greenfiber can be installed on top of existing insulation, given that it’s in good condition. Remember, you won’t need as much insulation if you already have existing insulation in place and you can use the insulation calculator for exact calculations based on your current insulation levels and desired R-value. 

Take a look at our Do-It-Yourself Attic Installation Instructions for more details on installing Greenfiber insulation yourself. 

When blown-in insulation is installed on an attic floor, it can also be referred to as a loose-fill application. When blown-in insulation is installed in a closed framing cavity, such as a wall or floor, it's called a dense-pack application. 

Dense-packed cellulose insulation can be easily blown behind netting for new construction projects, or holes can be drilled into existing walls for retrofit installations. The insulation is blown-in to fill around pipes, wires and other objects inside the cavity to eliminate costly voids and gaps, making it an exceptional choice for reducing air infiltration, providing great thermal resistance and sound abatement. Consulting a professional insulation contractor is advisable to determine the most suitable approach for your insulation needs.

Yes, cellulose insulation can be mixed with other types of insulation, such as fiberglass or foam insulation, provided it is not wet and that the existing insulation is in good condition. 

SANCTUARY® by Greenfiber cellulose insulation is ideal for providing additional R-value over existing attic insulation since it has the ability to fill in small crevices and hard-to-reach places that can be left open by other forms of existing insulation. 

To calculate the cost of cellulose insulation for your project, you will need to determine how much insulation you will need. To do so, take the square footage of the space and divide it by either the depth or the desired R-value. Our blow-in insulation calculator can help take the guesswork out of scoping and pricing for your next cellulose insulation project.

Cellulose blow-in insulation is one of the best choices you can make for your home. Made from recycled paper, it’s an environmentally friendly and sustainable option that does a great job of filling in all the nooks and crannies in your attic that other types of insulation can leave behind. Plus, cellulose is a superb air blocker, which means less heat escapes through cracks and holes in your walls. This results in lower energy bills year-round, as your home will stay warmer in the winter and cooler in the summer.

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