A Guide to Insulating Your Attic


One of the most important things that you can do is to make sure that your home is properly insulated. This will help your house stay warm in the winter and cool in the summer. One of the biggest ways that homes lose their efficiency is through the attic. So this blog will help you with understanding how to efficiently insulate your attic.

Your attic usually is insulated by using one type of insulation or even a mixture of the three insulation types. The type of insulation that you are using is going to depend on your space, like whether there is insulation already in the attic or the kind of access you’ll be using for installing your insulation, along with other factors. Insulation comes in three types:

Rolls and Batts Insulation – These lengths are pre-sized are called blanket insulation sometimes. They’re made to fit in between the framing studs of a house or when you’re using it in your attic, your ceiling joists. The batts are pre-cut and then sized for different uses, and rolls give a lot more material that you work with as well as being able to cover additional space. Both types can be used for most of the insulation projects in an attic.

Blown-In/Loose Fill Insulation – This insulation type usually is made of cellulose such as recycled paper and it’s blown in using some type of machine. It’s great for spaces and cavities that are difficult to reach. You can install it over blanket insulation that is already existing if you need to.

Foam Insulation – This type of insulation is sprayed into s space and it’s great for filling small holes and crevices. It will mold to different surfaces and set quickly. It’s perfect for blocking moisture. This type of insulation’s R-value is usually higher than the other two types and it forms a barrier against air, which often means that you don’t have to use other weatherizing, such as caulk sealing or putting up vapor barriers.

Just like the other types of insulation that is in your home, the most essential indicator of the way that the insulation is going to perform is going to be its R-value. That is why you want to pay special attention to it. Various regions are going to require higher R-values when compared to others. For example, the northeast and the southwest are going to require different R-values. For all of the regions, the R-value of the insulation is going to be from R-30 – R-60. In general though, adequate insulation is going to be approximately R-38 or around there. The R-value needed also is going to depend on if your attic is insulated already. If you aren’t sure about what will be good for you, it’s a good idea to speak with someone at a hardware store to get some advice.

A simple way that you can see if your attic is adequately insulated is to go to the attic and examine the floor. If the insulation that is already there isn’t completely covering your joists, chances are it’s time to add some more insulation.

Add Insulation

Prior to adding any type of insulation, you should take a minute to plan out the project. Figure out where in your attic you’re going to need the insulation and the amount of addition R-value you’re going to need from the new insulation, if you’re adding more insulation. To discover the amount of R-value you’ll need to add, look at the insulation that is already there. If you’re able to figure out what the R-value is, subtract that from 38 so that you can determine the amount that you have to add. Then you want to decide what type of insulation is going to suit your needs the best. For the most part, adding some blanket insulation is going to be the best choice if you are doing it yourself. Finally calculate it by the square feet to determine the amount you’ll need to purchase. Batts and rolls usually will come in widths of 16 inches or 25 inches so that they are able to fit in between joists. Either one can be cut so they’re able to fit in between the joists, with your utility knife. The insulation amount you’re going to buy is going to be determined by the rolls and batts lengths and the amount of attic space you’re insulating.

The blown-in type of insulation is pretty simple to install. However, you have to use specific equipment to get the job done. In the majority of cases, a contractor will add it when they are building the house. Since they already have access to the equipment they need for installing it, it’s a good idea to think about hiring someone professional if you’re planning to do Blown-in insulation is fairly easy to install but requires specific equipment for the job. In most cases, it is added in new builds by contractors. As they have ready access to the required equipment to install it, consider hiring a professional if you want to add this type of insulation to your attic.

It’s important that you are sealing all of the air leaks in your house before you add insulation to the attic. This is going to make it a lot easier to locate any types of leaks in your attic as well as overall help with the efficiency of your home. Spray foam made of polyurethane is great for sealing your air leaks as well as creating a moisture/vapor barrier.

Below are the steps you want to take for insulating your attic

Apply a Vapor Barrier

Although this is an optional step, this is also a good one to take. This will be installed in between your joists before you install blown-in, rolled or batt insulation. This is a good choice because it will keep the moisture away from your insulation and helps keep vapor from going through. This barrier usually is created using plastic sheeting that has been cut so that it will fit in the joists, then added before your insulation. If you’re adding to existing insulation, the barrier that was originally there will be enough.

If you are using batts that are faced, they’ll provide this vapor barrier. You have to install your facing material down (facing your attic floor). Facing is attached to your studs and joists with your staple gun. Rolls and batts that aren’t faced ought to be used if your attic already has an existing vapor barrier or if you’re adding to insulation that already exists. It’s not necessary to have multiple vapor barriers. It’s also important to check with the building codes in your area to make sure you’re installing your insulation so that it matches regulations.

Get Ready to Insulate

Start out by measuing the area in between the joists using your tape measure. This will let you know the width of the insulation that you have get. Make sure that you’re also measuring your length so that you’re able to cut it accordingly. Open up your isnulation by cutting it lengthwise using your utility knife. Make sure you’re not cutting the facing or insulation. The roll must be measured as well as cut so that it’s fitting in between the joists in your attic. Cut it around an inch wider than needed so that you’re sure the insulation will fit snugly in between your joists and fill your space properly. Use a sturdy, hard surface and utility knife for cutting your insulation.

Safety Tips

  • Bring a portable light when you’re working in your attic so you have enough visibility for working as well as knowing where you are stepping. The last thing that you want to do is to step accidentally in between your joists so that you push one of your feet through your ceiling or fall.
  • Bring a material such as a plywood panel to use for your work platform so that the job is safer and easier if there aren’t safe places for you to step.
  • Wear a shirt with long sleeves, gloves and pants so that the fiberglass insulation isn’t causing irritation to your skin.

Wear a mask and safety goggles while you’re working in the attic. This is going to help you avoid throat and eye irritation because of insulation and attic surfaces’ debris and dust.

Install the Insulation

Unroll your insulation and then push it in or place it on the spots in between the joists. Make sure the roll is totally flat inside. It’s then possible to expand it so it’s filling the whole space. The insulation piece should be fitting snugly inside that space. If you’re using insulation batts or rolls that are faced, make sure the facing is facing your attic’s floor to stop the vapor. You can staple your flanges of the faced insulation right to your surfaces such as the joists, but this might not be needed. Insulation that is faced should be fitting snugly in without being secured.

It’s possible to get additional R-value by laying your new insulation rolls across your existing insulations in a way that’s perpendicular to your existing insulation.

When you want to make sure your room is more comfortable, insulating your attic is one of the best ways that you can do it. Use this guide and you’ll find that your energy bills are less and that your home’s a lot more comfortable.

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