It’s true, you can install your synthetic roof underlayment and save hundreds of dollars compared to hiring a roofing contractor.

If you want to learn how to install synthetic roof underlayment, you’ll find it easier than you think if you follow these 5 easy steps below.

Step 1. Prepare the surface

To start the installation process, you’ll need to make sure that the surface on which the synthetic roofing is going on is clean and free of any debris.

Begin by vacuuming and brushing away any leaves or other natural items such as pebbles, as these can cause problems when installing, Inspect the surface for any cracks or gaps around doors or windows, as these will need to be filled before moving forward with installation.

If there are any gaps, use a thin layer of tar-based sealant to fill them in. Make sure that the sealant is only applied where necessary; excess sealant can prevent water from escaping properly and cause leaks. Once the surface has been cleaned and inspected, it’s time to get started on installing your new synthetic roof.

Step 2. Roll out your tape

1. Measure your installation surface This ensures that you buy the right length of tape to fit your project, and it also helps make sure you don’t waste any product. You’ll need at least three feet (about one meter) of tape for each direction in which the tape will be installed.

2. Unroll your new adhesive-backed roofing mat by pulling up the release tabs on either side of the roll until it reaches the top.

3. Find the start edge of your tape and peel off about a foot or two.

4. Place the unpeeled strip against the backside of your mat so that it is centered and flat across its width, then use a razor blade or utility knife to cut through both layers of material, be careful not to press too hard as this can cause undue stretching or tear with some types of roofing mats.

Continue cutting strips in this manner down the entire length of your mat until you reach the end. Fold over the first strip and stick it to itself on the underside of your mat, leaving an airtight seal that won’t let water seep underneath.

Step 3. Trim around windows and doors

Remove the excess roofing from around windows and doors. You can do this by hand with a knife or shears or you can use a cordless grinder or circular saw.

Be sure to wear proper protection as these tools may be hot, loud, and dusty. When trimming around your door or window, don’t trim too close to it. You want at least 1/2 inch between the door jamb and your trim line so that it is still protected.

Do not put new underlayment on the old stuff: if you have any existing shingles, siding, or other material on top of your house’s surface where your new roof will go, take them off first before installing the synthetic roof underlayment.

Doing this ensures that no seams are running through the middle of your roof and it will also help avoid any possible leaks due to improper installation.

Step 4. Seal seams

Mix the liquid roofing adhesive with water, then spread it with a trowel or brush. Start at the bottom of your project and work up to the top.

Make sure that the top layer is always wet so it will seal together tightly when it’s done. Press down firmly as you go until all the seams are sealed and try not to get too many bubbles on your surface.

If you do get some bubbles, don’t worry- they’ll pop when the adhesive dries. If you’re planning on painting your new roof later, this is a good time to prime it for painting.

  • Use an oil-based primer if possible because it has better adhesion properties than latex primers.
  • Keep a small amount of primer in a separate container and pour it into another container before applying it to your roof.
  • Use this method rather than pouring directly from the can onto your rooftop, which can cause air bubbles to form.

The next step is waiting! Your new synthetic roof installation should be dry within 24 hours; however, most companies recommend waiting at least 3 days before exposing the installation area to direct sunlight or rain.

Step 5. Admire your work

Your freshly installed synthetic roofing system will make your home more environmentally friendly and cut down on your energy bills.

Plus, you get bragging rights for the next decade or so! Now that you’ve learned how to install a synthetic roofing system in five easy steps, give us a call today to set up an appointment with one of our knowledgeable professionals, we look forward to helping you take advantage of this innovative new way of living.


The next step is to lay out the tarp so that it covers the entire surface of the top layer. To secure it, you can use nails, stapled clips, or spray adhesive.

Nails are good for quick and easy installation but are not as secure as staples or adhesive. You can also use hot glue if you have time, but remember it is not good for all surfaces. One way to find out if your material will work with hot glue is by using a small amount on an inconspicuous area of the tarp before proceeding with the rest.