What is Roof Cement?

Your roof, though immensely durable, isn’t completely immune to damage, even with the tough exterior surface of its shingles to help protect it. That’s why there’s such a product called roof cement.

What Is It?

Roofing cement is a multi-purpose material that patches surfaces, working like an adhesive to repair holes and leaks in roofing systems.  Roof cement is comprised of a variety of different materials: asphalt, refined mineral spirits, non-asbestos reinforcing fibers, and plasticizers.

What Can It Do?

It can repair more than holes, too, like fixing rust spots, securing joint connections in gutters or metal trim that leaks, and plugging up leaks found in the flashing surrounding chimneys, valleys, and coping.  Because roof cement had adhesive properties, it can also hold down loose asphalt shingles to your roof.  Roof cement can also fill in cracks in concrete.

How to Use Roofing Cement

First, clean the area you’re about to work on.  You’ll want to really try to remove as much dust, dirt, and debris as best as you can, otherwise you’ll be inviting it to stick and clump with the roofing cement when you go to apply it.

Weather must be on your side when you use roof cement.  Roof cement is best applied in dry conditions, so try to choose a day to work on this repair project when there’s no rain and your conditions aren’t damp.  If you absolutely need to get out on your roof and the weather isn’t in your favor, then pick up a roof cement with a formula that’s designed to stick to wet or slick surfaces, so your work doesn’t get washed away in vain.

Using a trowel or putty knife, apply the roof cement into the crack or hole until filled.  For regular roof cement used in dry conditions, don’t thin it out.  If you’re using a wet-surface formula, smooth the cement both into the surface you’re repairing and around the area as well.  Use a thin surface coat that’s about 1/8 inch in thickness.

You can apply more coats with roof cement—and you should if it is a bigger repair or patch job.  You’ll need to wait for the roof cement to dry completely, however.  Read the manufacturer’s instructions to see how long it will take, although you can safely assume that it will be about twelve hours.  Now, if it really is in fact a big patch job you’re tackling, then you’re going to want to take this three-step approach:

  • Help bridge large gaps or cracks in the roof system with materials like polyester or fiberglass fabric or rolled roofing.
  • Coat over the material that you’ve set in place liberally with roof cement.  Stamp the patch down firmly, packing the cement into the patched area to ensure the damage has been covered and addressed.
  • You’ll definitely want to apply another coat if the crack or hole required extra material to help with the repairs.  As mentioned before, wait the appropriate amount of designated drying time, then reapply another thick layer of roof cement to the area.  You can add an additional one to two more layers of roofing cement on top of the original.

For reference, about one gallon of traditional roof cement covers an approximate 12 square feet when applied at 1/8-inch thickness.  For large repair jobs, you’ll want to consider picking up an extra gallon or two at your local hardware store so you won’t have to make another trip out mid project.

Be Warned: Roof Cement Is Not a Permanent Fix

Many homeowners are so involved in their desperate attempt for a quick, cheap, and easy solution to fix their roof, that they forget that by opting for roof cement, they could be doing a lot more harm than good.

When homeowners begin to use roof cement as a solution for repairs found near walls, skylights, chimneys, and beneath shingles, then there’s cause for alarm.  More leaks can form in these delicate, structurally integral places because water flow can become restricted, thus pooling up and inciting further damage.

Don’t use roof cement in these situations:

  • As a permanent patch
  • As an alternative to roofing nails
  • As a replacement for the roof’s underlayment
  • To avoid calling in a trained roofing professional to do the fix
  • Your roof deserves a permanent fix, so roof cement should only be utilized as a temporary resolution until you can contact a professional roofing contractor to inspect and repair your roof with proper materials.

The roof system depends on each layer to work and keep water channeled out of your home, so if there’s damage to parts like the shingle or underlayment beneath it, the entire system could be compromised.  Roof cement will keep water out—for now—but more than likely you’ll need a new waterproofing underlayment or shingle replacement to ensure the system is sealed.

Consider the overall cost of your roof.  It’s likely worth a few thousand dollars.  With that in mind, you wouldn’t want roof cement as anything more than a Band-Aid to any damages it may be suffering from.

Always Go with Professionals for Roof Replacement and Repair

Whenever you’re making improvements to your home, you always want to go with professionals. This is essential to quality, safety and security. But as a customer, don’t be afraid to speak up and trust your gut. Enjoy your home for years to come knowing there’s a solid roof over your head.

At Feldco Roofing, we provide breakthrough design and triple layer protection to keep your roof insulated throughout the year. For a roof replacement, our installers are factory trained, experienced and professional to get the job done correctly. Speak to a product specialist and get a free quote online today.

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