December 11, 2023

Roof Cement 101: How To Use the "Duct Tape" Of Roofing

Uncover the power of this quick-fix tool. There's a reason we call roofing cement the "duct tape" of roofing.

Time to read:
5 Minutes
Written by
Nicholas Capobianco

A roof leak can cause chaos in a home. Homeowners need a new roof but can't wait, so they look for a quick solution. This is where roof cement comes in.

You may have called it the “duct tape” of roofing. This comparison really does work:  It doesn't look good, it's cheap, and works as a universal quick fix.

Unfortunately, there's a lot of misunderstanding around roof cement. Homeowners can wrongfully use it to patch an asphalt roof back together assuming it can "fix" their roof. But that's not what it's for.

In this blog, we're diving into roofing cement. We're exploring:

  • What roof cement is
  • Roof cement VS roof sealant
  • When to avoid it and when to use it
  • How to use it properly

What is roof cement?

Roof cement comes in several different types, and not all of them do the same thing. Some ads tend to associate the term “cement” with anything sticky that stops a leak.

Roof cement is an emulsion made of asphalt, fibers, mineral spirits, and other additives. Hardware stores sell it to homeowners who want to slow the torrential downpour in their living rooms. Asphalt roof cement is the staple.

Simply put, it’s a material used to temporarily seal leaks, reattach loose shingles, or repair small roof issues. Think of it as a thick, sticky, multi-purpose tool that gives homeowners a short-term solution to an immediate problem.

roofer on a house applying roofing cement

Roof cement VS roof sealant

People sometimes confuse roof cement with roof sealant.

Roof sealant is used to create a waterproof seal between shingles or roofing material and roof features like vents, chimneys, etc. It's used in roofing as a tool, not as a quick fix.

Roof cement is a patch item to help fix leaks, reapply shingles, and other roof repairs.

When to avoid roof cement

Not every leak can be fixed with a liberal scoop of roof cement. In fact, using too much can cause additional damage to the roof.

Homeowners sometimes use it without fully understanding it. They over apply it near walls, skylights, chimneys, and under shingles, which can restrict the water flow on the roof. As roofers know, this can ultimately lead to more leaks. But homeowners don't know that.

Appropriate uses for roof cement

Yes, roof cement is a patch, but there are cases when it is absolutely appropriate.

Use it to:

  • Repair small holes
  • quickly fix for loose shingles
  • Seal gaps around chimneys and corners
  • Professionally apply a temporary fix before permanent repairs

Roof cement is useful for temporary repairs, but it should not replace getting a new roof. 

Man applying roof cement to tile shingles

How to use roof cement

First thing's first when getting on a roof: think about safety. Whether you're patching a homeowner's roof for bad weather or doing a full replacement, put on your harness and other safety equipment.

If you're new to roofing, be sure to read the instructions on the roofing cement. You'll also want to make sure that you have all of the tools that you’ll need before you get started.

With the safety gear and tools, you're ready to do.

Assess and clear the area

Make sure that the area is free of debris and that you’ve removed any materials that could complicate the application. This is as much for proper adhesion as it is for safety.

We know you want to help homeowners no matter what, but if the roof isn't safe to get on, don't do it. We know water is scary in a house, but in extreme weather, you should not be climbing onto a roof.

Find damaged shingles

Look for damaged shingles, and any obvious signs that areas of the roof are damaged. It can be a good idea to get homeowners to point our any leaks before you climb up so you know where to look. Once you’ve identified the problem, you can start gluing shingles back into place.

Damaged shingles coming off a roof from wind storm

Use your trowel and putty knife for cracks or holes

Identify the borders of the hole or crack that’s letting water in first. Gently use your trowel or putty knife to pack the roof cement into the area. Don't push too hard or be too aggressive, or you can cause further damage.

Consider patches to help with larger areas

For large areas of damage, use rolled roofing, fiberglass, or polyester as an extra patch. Coat the back of the material with roof cement, and then apply another coat over the top for maximum protection. Again — this is a quick fix! Don't do this when completing a new roof replacement.

Replace the shingles

After the area has been repaired, it’s time to replace the shingles. If you can't replace them right away, tarping the area is a good temporary option.

If you do have to reattach shingles, start at the bottom. Use roofing nails to attach each shingle from bottom to top. Then, use a small amount of roof cement to secure the final shingle.

Tree fallen on a roof causing major roof damage

Insider tips and warnings for using roof cement

Roof cement is available for homeowners, but they shouldn't mistake themselves as a roofer. If you are using roof cement to patch Before climbing that ladder and tackling your roof repairs, there are some things to remember:

  • When working in colder weather, leave your roof cement inside overnight.
  • Avoid using roof cement while smoking or around open flames.
  • Check the weather before planning your roofing project.
  • Make sure that the roof cement you purchased is the right formula for your needs.

Educating homeowners on quick fixes

If you're doing a patch job with roofing cement on a house, make sure to walk homeowners through the points explored here. Talk about how:

  • Roof cement is a patch job.
  • There are limitations and dangers of over-using this fix.
  • It's still important to do a permanent fix for roof leaks.

If you do offer patch jobs and roof repairs, make sure you have a process in place to track those customers and nurture them. Email, text messages, follow-up phone calls, and other marketing efforts can help convert those one-time customers into a full-on roof replacement.

L‍earn more about our CRM and how it can help you manage your leads. Or, book a call with our team and see our tools in action.

Join Roofr, get a free roof measurement report
Get started

Want the latest roofing tips & tricks?

Be the first to know the best roofing & business tips, and discover more efficient ways to grow your business. Subscribe to our newsletter to stay up to date (and ahead of your competition).

Leave a comment...

Join thousands of roofers who successfully streamline their sales process with Roofr

Get started for free
a close up view of a metal roof