Do you need new insulation?

How to Prepare and Insulate Your Own Attic

The best way to air seal and insulate your attic so your house does not lose all the heat it needs to keep you warm this winter. Getting your loft up-to-speed with insulation is among the most cost effect measures to help your home be more energy efficient.

1. Your 10 years old and enjoying hide-and-seek.

2. Your 32 years old and you’ve got one more valuable heirloom to keep away for ever.

3. Your 54 years old and you’ve noticed a wet spot on the ceiling and you are afraid that the roof is leaking.

All these are good reasons to enter the attic, but for now, let’s enter the attic to look at the insulating material and determine if adding more insulation would be a good – house warming – lower the energy bill – thing to do.

Building codes effecting insulation levels did not actually begin to take affect until the early 1980’s. If your house was built prior to 1984, there is a fairly good chance your attic has minimum attic insulation. Today, depending on the homes place, attics are being insulated with 16 inches of blown-in fiberglass ( R-49 ), cellulose, or shredded blue jeans.

Yes, shredded blue jeans, I am serious, the ripped up blue jeans were being installed in a wall as insulation.

Attic insulation is energy efficient if you live in a cold climate and you are trying to keep the warm in and the cold out, or if you reside in a warm climate and you’re trying to keep the cold in and the warm outside.

Dark colored, metal fiber appearing insulation is probably rock wool. A favorite attic insulation from the 50’s and 60’s. Fairly effective and not a health hazard. However, insulation granules which are roughly 1/4 inch square that feel like Styrofoam and comparison from mirror glistening to dark in colour might be vermiculite asbestos. This is bad stuff because of the asbestos content. My urge to attics with vermiculite is to have it professionally removed. Don’t handle or disturb this insulation without the direction of a professional contractor.

Tip – Don’t mess with knob and tube wiring and do not handle vermiculite.

If your home was built prior to 1940, you want to be aware of knob and tube wiring. This is clothed bound wiring that is attached to ceramic knobs as it runs over wood framing structures or runs through ceramic tubes when the cable runs through holes in the framing or construction material. This sort of wiring will need to be replaced by new electric wiring by an electrician before insulating. If you insulate directly over knob and tube wiring, the wire can heat up and create a fire danger.

One more thing, watch where you step when in the attic, only step on the truss or rafter framing lumber. If you step between the framing members you’re going to stick your leg through the ceiling and have one ugly hole to spot and one heck of a mess to clean up before the little women gets home.

Tip – to provide a place to put your feet while you work on sealing the attic floor, take a sheet of plywood into the loft which will reach over several rafters.

Tools and materials needed:

1. Basic face mask and mild coveralls.

2. Drop light so that you can see what you’re doing and where you’re going.

Tip – miner style head lights work great here.

3. For those who have a flue or chimney running up through your attic, or recessed lighting or ceiling fans, you’ll require a little roll of light weight metal flashing, 18 to 24 inches wide. One set of tin shears.


5. Tube of cheap general purpose caulk and a caulk gun. In case you have gas appliances, also pick up a tube of high temperature caulk.

6. Cardboard port chutesfor placing between the roof trusses in precisely the identical location as each eve port or bird block. Count how many you’ll need by counting the amount of eve or soffit vents from outside the home. The simplest tool to install the chutes is with a squeeze or tacker stapler.

7. Extra cardboard to use as obstacles to different areas where you don’t want insulation.

8. 1/4 inch, #6 sheetmetal screws and a cordless drill.

How to prepare the attic prior to installing insulation:

1. Remove the items you have stored in the loft that were placed over the heated area of your home where you are going to insulate. Items stored over the garage can stay. Boards that were placed in the attic to store items on also have to be removed.

Tip – Have a garage sale.

2. Take the port chutes and the tacker stapler and put in a chute at each location where there is an eve vent. Fit the chute so insulating material can’t block the port and a flow of air can move from the outside, through the eve port, up through the chute and out into the loft. Attic ventilation is important for the health of your loft.

3. Cut a half circular pattern from the edge of the metal and put in around the pipe like a collar, screw set up with the sheet metal screws by screwing through tabs wrapped up on the sides of the metallic and screwing to the framing members of the truss. Put one half collar on one side of the pipe and a half collar on the other. Caulk the space between the flashing and the pipe using the high temperature caulk.

Tip – when working with the thin metal, wear gloves to avoid getting cut by the metal.

4. Use the sheet metal screws to hold in position. These cylinders should seem like extra tall turtle neck sweaters on a metal neck.

5. In case you have recessed lighting or canned lights ( same thing), locate them in your loft. Older canned lights that you can’t cover with insulation will not be IC rated. Don’t confuse a UL rating ( Underwriters Laboratory ) using the IC rating. They are not the exact same thing. A UL rating means the canned light has a cutoff switch installed which will turn off the light if it gets too hot. An IC rating means it’s safe to cover the canned mild with insulation. Air distance between the IC rated insulation and light is not needed.

Tip – Now would be a good time to upgrade the recessed lights to shut cans and IC rated.

When the canned light is IC rated, seal the light in which it comes through the ceiling with overall purpose caulk – your ready to install insulation over the light.

If the canned light isn’t IC rated, seal the light where it comes through the ceiling and any holes in the light body with high temperature caulk. Form a cylinder with the metal flashing and put it around the light body like you would a flue pipe leaving a two inch air space. Hold it in place with the sheet metal screws. This should look like a gardener that places an open end bucket over his young tomato plants so that they are protected in the cold. The plant is the can light and the bucket is the sheet metal.

6. Locate any exhaust fans, there might be none, one or more. The fans need to have a ridged or flexable round duct running from the fan to an exhaust point that places the exhausted air outside and not in the attic. Use the all purpose caulk or the foam spray to seal the fan body in the ceiling. Use the caulk to seal the holes in the fan body. Be sure the duct is exhausting to an eve vent or a roof summit vent. Support the duct with plastic or wire ties to make certain that the duct does not fall down with time. An exhaust fan has a one way flapper valve in the exhaust fan just before it attaches to the duct. Given the chance, inspect the flapper valve and be sure lint, dust, hair, moisture and gunk hasn’t left the valve stuck open or glued shut. The flapper valve is a back flow restrictor, maintaining warm or cold air from coming back down the duct in your house.

Tip- Now would be a fantastic time to replaced older noisy exhaust fans. I suggest an exhaust fan rated at 100 cfm (cubic feet per minute ) or more and on the quiet side.

7. Now take the can of spray foam and apply foam to every hole in which an electric wire, T.V. wire, or telephone cable enters or leaves the loft. Do the same for the plumbing pipes. There ought to be port pipes running up from the attic floor and out the roof. Foam where the pipe comes through the attic floor.

8. Some homes, both older homes and newer, may have open framing spaces that run from the attic floor to the floor below. These are spaces that result from unnecessary space at the end of bathtubs or closets. They maybe caused by irregular framing like a triangle formed where a cupboard meets a hallway that matches a bedroom door. These open chases need to be sealed with more than just insulation. Take a piece of cardboard, cut it to fit over the opening, lay a bead of purpose caulk around the lip of the opening, lay the cardboard on top the the caulk and twist down with the sheet metal screws. Now you just insulate over the cardboard.

Ready to Resist

1. Tape measured- for calculating the square footage in your attic and for marking cardboard strips with the depth of insulation you want to add.

2. Either one is good.

3. Insulation – Large hardware and building stores will have a blower you can use should you buy the insulation from them. Don’t forget to call ahead and book the machine. The blower includes about 2 miles of hose.


5. Attic access tent- This is a rarely new item for insulating over the attic access opening after you have insulated the rest of the attic.

6. 1/4 inch self adhering foam weatherstripping.

7. Gate latch – two little gate latches for holding the access lid down.

8. One buddy – flip a coin, 1 person to spray the insulation in the attic and one person to feed the machine in the garage or back yard.

Take the tape and measure the width and length of the loft space. This can usually be done from outside the home by walking around on the lawn instead of in the attic walking around on narrow trusses. Plug the numbers into a calculator with a multiplication sign between them and calculate how many square feet are in your attic.

Take a trip down to your favorite hardware store and head for the insulation department. The bags of insulation for loose fill or blown in insulation will be square compressed packages. Grab a bundle and read how much insulation is in the package at a particular thickness or depth. The chart on the package will allow you to calculate the number of packages of insulation you will need if your attic is so many square feet and you want to add as much R-value. As an example, 1 package will cover 100 square feet at R-16, 56 square feet at R-30, and 32 sq ft at R-49.

Tip – purchase a bundle or two extra, once you start blowing insulation you do not need to stop to go get one more bundle.

Load up the mill and the insulation in the rear of the pickup and head home for a good, energy saving afternoon.

Place the blower at a handy location. You’ll have to plug the machine in to an electrical socket, feed it with bundles of insulating material, and run the hose from the machine into the loft. Tack up a few of the cardboard depth indicating strips that you made so you have a target depth to aim for. Spray the insulation from the hose in a sweeping movement that allows the insulation to fall in your attic floor like a fine light snow. Fill 1 section of loft to the intended depth before moving on to the next section. Be careful not to direct the flying insulation to the eve chutes or within the cylinder barriers.

Tip – If your attic has an electrical junction box or some other fixed item that will be tough to find once covered with 16 inches of insulating material, mark it’s location by writing on a piece of cardboard and stapling the signal over the thing on a roof rafter with an arrow pointing the way.

Fill the entire attic with fine new insulation to an even depth indicated by the cardboard thickness measuring strips placed effectively around the loft. As soon as you have all the attic filled except just the area around the attic access opening, stop for a minute, take some cardboard, and put in an insulation barrier around the opening. Now you can add insulation to the proper depth right up to the opening.

Tip – Plan ahead so the hose and the blower hopper is not full of insulation when you are finished and need to take the hose off the machine.

Hey, you are almost done.

1. Spread the loft access tent over the opening.

2. Twist the 1/4 inch self adhering weatherstripping into the contact perimeter of the lid that fits into and covers the access opening.

3. Install the hatch latch clips, one on either side of the lid in such a way that if the latch is fastened, it pulls down on the lid and compresses the weatherstripping so the lid is air tight.

4. Load up the additional bundles of insulation and the blower and come back to the store.

There is bound to be a light sprinkling of insulation under the access opening and around the area where the blower was found. Brooms do not work real well on insulation in grass or carpet. Catch the vacuum cleaner and don’t stop until your sure you won’t have to sleep on the sofa.

You will now receive the satisfaction of a lower power bill, a warmer feeling, less drafty house, and a furnace that doesn’t have to work so hard. Hope this report has been a help, please come back soon and hurry, I won’t be leaving the light on for you…