rood decay

18
Mar

Common Low-slope Roof Problems : Part 2

low slope roof decay

Shingle failure

Common Low-slope Roof Problems

In our previous post we noted that many “standard” housing units in the United States primarily use what is considered a “low-slope” roofing style and some  of the common issues with low-slope roofs by highlighting an article by Jane Madison at Builders Magazine.  Below is the wrap up of the most common problems.

PUNCTURES AND THE ADDITION OF PENETRATIONS POST-INSTALLATION

For all owners, but especially those with single-ply or spray polyurethane foam (SPF) roof systems, damage from foot traffic can be problematic. “Punctures are something on high-traffic areas that can be a problem,” says Harriman of single-ply systems. “One of the things we like to do is add walkway paths or extra sacrificial layers of membrane.”

C.A.R.E. notes abuse of the finished roof as one of the nine most common problems plaguing single-ply systems, stating, “Heavy construction traffic can cause scrapes/cuts in the membrane and damage to the underlying substrate. In addition to leaks, this can cause premature problems with the roof membrane and may void the guarantee.” Limit traffic and conduct cursory inspections after tradespeople have been on the roof.

All roof systems’ performance is compromised when new equipment and penetrations are added to an existing roof, unless proper precautions are taken. When penetrations are added and deleted from a metal roof, the results can be disastrous. “You are sometimes left with a compromise and a lot of caulking and sealants. Metal roofs move a lot. There is a lot of expansion and contraction, and if you are left to deal with caulking, you’re probably going to have problems eventually,” Harriman warns.

SAFETY

The installation of hot bituminous and torch-applied mod bit systems requires strict adherence to safety procedures. Overheating asphalt can result in burns, and fires in the kettle and on the roof, C.A.R.E. warns. In torch-applied mod bit applications, fire extinguishers should be present and MRCA CERTA program guidelines should be followed.

During installation, odors from cold-applied mod bit systems can cause discomfort and alleged illness among building occupants. Outside air intakes should be covered in roofing areas, recommends C.A.R.E.

IMPROPER REPAIRS

Using materials that are not intended for application on specific roof types can result in permanent damage to the roof. “One of the most common problems we see with metal roofs is improper repair. People go up with caulking and plastic roof cement and improper materials that are in no way intended for that purpose,” Harriman says. “You can make a small problem worse through that improper repair.”

Pierce agrees. However, this problem isn’t exclusive to metal roofs. “On a built-up or modified roof, that five-gallon bucket of plastic cement can solve a lot of problems. But if I take that five-gallon bucket of plastic cement up on a single-ply membrane, I may actually damage the membrane itself,” she says. Follow the manufacturer’s instructions for proper use and take note of repair products with a shelf life.

SHRINKAGE

Single-ply roof types are each unique. “If you walk out onto an EPDM roof today, one of the first things you’re going to look for is evidence of shrinkage,” Harriman notes. “The two most common things I see, especially on ballasted membranes, are pulling of the flashings (which is due to shrinkage of the field membrane) or you could have deterioration – surface crazing and cracking of uncured membrane, commonly used at perimeter and penetration flashing

BLISTERING

Blistering, ridging, splitting, and surface erosion are symptomatic with BUR, and can eventually lead to bigger problems. While blisters are not always worth fixing, one of significant size should be addressed. According to C.A.R.E., inadequate attachment of hot bituminous roof systems due to asphalt heated to an improper temperature can cause blistering, along with the slipping of felts, and accelerated aging. Bad interply integrity and dry laps can also result in the appearance of blisters.

Voids and holidays can be problematic in the application of torch-applied modified bitumens. “If the membrane is not torched properly, it will result in delamination, slippage, and blisters,” the C.A.R.E. CD-Rom reports. Moisture and air trapped in modified bitumen roofs can vaporize, causing a blister. “Many times it’s non-threatening, unless it’s affecting the lap area and then it probably needs to be repaired,” says Harriman.

With cold-applied mod bit systems, the entire membrane should be installed in the same application (i.e., scheduled around work breaks and/or holidays). C.A.R.E. pinpoints the consequences of improper sequencing of work as contamination and poor adhesion between the cap sheet and base ply: ultimately, blisters, delamination, leaks, and voids.

During the installation of spray polyurethane foam systems, recovering over a wet substrate can result in severe blistering and delamination, notes Harriman.

Ensuring a quality installation, providing the roof with consistent maintenance, and the early detection of problems through routine inspections can help maximize roof life. As the roof ages, the likelihood of problems increases. However, it is how these problems are addressed that will determine the fate and future of your roof system.

This wraps up the part two of the Most Common Low-slope Roof Problems. 

Thanks again to Jana J. Madsen (jana.madsen@buildingsmedia.com) the managing editor at Buildings magazine.   For more information about C.A.R.E., visit (www.gaf.com) or e-mail (care@gaf.com).


Want more information? Trying to understand the costs associated with replacing a roof?  Call, email, post to Facebook, or tweet to us. No Fee, No Obligation, Just help for you.

Don’t want to talk to anyone and just want a quick, satellite photograph measurement to help estimate the cost for your roof?  Order the Quick Report

If you have a specific roof issue and can send us a photo via email, Facebook, or Twitter, we will do our best to advise you on the specific issue

14
Mar

Most Common Low-slope Roof Problems : Part 1

Low-slope roof in Chicago

Low-slope roof in Chicago

Common Low-slope Roof Problems

Many “standard” housing in the United States primarily uses what is considered a “low-slope” roofing style.  So what are some of the most common issues with low-slope roofs?

“Obvious or unforeseen, roof problems are always a pain and undoubtedly a significant expense,” says Jane Madison at Builders Magazine, who posted a great article about low-slope roof issue.   Below I posted the first part if her article.

Problems Plaguing Low-slope Roofs

Buildings magazine examined which problems are most common and the conditions that can either cause or be the result of premature failure and reduced service life of low-slope roof systems. This is not a self-diagnostic guide, but rather an informative list of some of the problems most often battled by building owners and facilities professionals.

“If you look at a failure curve, most roofs are the best they’re going to be at the time they are installed. The curve is pretty flat in terms of their deterioration for the first several years, and the last 25 or 30 percent of the roof [life], the curve becomes more steep,” explains Ron Harriman, vice president, Benchmark Inc., Cedar Rapids, IA. Unfortunately, problems are inevitable as the roof ages. Without proper and routine maintenance, these minor problems can even become catastrophic.

ROOF LEAKS AND MOISTURE

“With any roof – no matter what type – if you’ve got roof leaks, then you’ve got a problem,” explains Charles Praeger, executive director, Metal Building Manufacturers Association (MBMA), Cleveland.  Leaks can occur for a number of reasons. Built-up roofs (BUR) might experience leaks due to flashing details that weren’t fastened properly during installation. “The problems an owner is typically going to have [with a BUR system] is that 95 percent of leaks occur at flashing details – anywhere the membrane itself is terminated or interrupted,” explains Helene Hardy Pierce, director of contractor services, GAF Materials Corp., Wayne, NJ. Additionally, hot bituminous and torch-applied modified bitumen roofs may experience leaks when a proper moisture barrier is not installed underneath a coping cap on parapet walls, according to Avoiding Common Roof Installation Mistakes, a CD-Rom produced by the Center for the Advancement of Roofing Excellence (C.A.R.E. Ltd.).

The C.A.R.E. CD-Rom also pinpoints improper installation of flashing as a source of leaks on torch-applied modified bitumen roofs. Inadequate head laps and backwater laps are another mod bit installation problem that can allow moisture infiltration. “Water can get under the membrane if the field of roof is installed so that water flows against the lap. The consequences of backwater laps are leaks and blisters, which can lead to roof failure,” C.A.R.E. explains. With cold-applied modified bitumens, improper storage of materials can result in moisture infiltration built into the roofing system, and under-application of adhesive can result in poor lamination and roof leaks.

Leaks can result when single-ply membrane roofs are installed with poor seams. “You’ve got to have good seams with single-ply, because if you don’t, you don’t have much. The membranes themselves will hold water. You’ve got to have the seams either glued or heat-welded properly,” Harriman explains.

BLOW-OFFS, TENTING, REDUCED WIND UPLIFT RESISTANCE, AND BILLOWING

Leaks are not the only problem that can result from improperly installed flashing. Hot bituminous roofs where flashing is poorly attached may experience open seams and laps and ultimately cause blow-offs, reduced puncture resistance, and code issues, advises C.A.R.E. Poor gravel embedment and the use of an inadequate number of fasteners in the base sheet during application of both hot bituminous and torch-applied mod bit roof systems can also have similar consequences.

Wind uplift resistance can be reduced greatly if seams are not cured adequately on cold-applied mod bit systems. C.A.R.E. notes, “Seams made with cold adhesives do not have good integrity until the adhesive has cured. If the seams are exposed to wind and rain before they are properly cured, moisture can infiltrate the roof system or wind uplift can damage the roof membrane.”

If not adhered properly to the substrate, single-ply roofs are at risk for blow-off and billowing. “With single-ply membranes, we do a little more to hold things in place, and if it’s not done properly, then we end up with tenting of the flashings [and] we end up damaging the membrane,” says Pierce.

POOR INSTALLATION AND UNSATISFACTORY WORKMANSHIP

A faulty installation dramatically increases the likelihood of problems and reduces a roof system’s life expectancy. “Workmanship does tend to be one of the more common problems or common reasons for problems that crop up at some point in the life of the roof,” Harriman comments. BUR system installation can be problematic if specific preparations are not taken. According to Harriman, problems with adhesion can result when the area isn’t cleaned, dried, and primed properly prior to installation. “Those are things that are difficult to walk up on a roof and visually see, but could lead to future problems, premature aging, or premature failure,” he says.

Torch-applied mod bit system performance can be compromised if crews do not relax the sheets prior to installation. Material preparation is important to a quality installation. C.A.R.E. notes, “Sheets installed that have not relaxed or are installed when ambient conditions such as temperature are not right can result in wrinkles, leaks, fish mouths, contraction of sheets, or blisters.” Be sure that the contractor and crew you’ve hired are educated in proper installation techniques specific to the roof they are installing.

LACK OF MAINTENANCE

There are many reasons not to neglect the roof – including financial and business continuity reasons. Being wise to problems can prevent their escalation. “The problem in roofing is a lack of education on all levels. But if the owner of the property is better educated, the whole industry does better and less problems [occur],” explains Chris Mooney, GAFMC/C.A.R.E. national training manager, C.A.R.E., Wayne, NJ. Specific levels of maintenance are required to prevent voiding the warranty. “Perform routine inspections. You don’t have to know a lot about roofing,” Pierce explains. “Things like ponding water, a piece of slipped base flashing, pitch pockets that haven’t been filled – those should be obvious whether you know a lot about roofing or not.” Addressing minor problems before they escalate maximizes roof life as well as minimizes headaches and expense.

PONDING WATER

“Another common problem across all roof types is what I call ‘incidental ponding water.’ If we move the water off the roof, the roof has a really good chance of performing the way it should,” notes Pierce. During the design of a dead-level roof, slope should be added with tapered insulation or crickets. “If we don’t take proactive measures when we’re actually designing the roof, then we’re building in ponding water,” she stresses.

UV rays compounded by ponding water can have adverse effects on BUR and asphalt-based mod bit roofs. During installation of hot bituminous systems, C.A.R.E. warns that improper mopping can produce voids in the membrane, block drains, and result in ponding water as well as void the warranty.

Pierce cautions that before roof repairs are hastily made, the source of the ponding water should be investigated.HVAC units without condensate drain lines could be the culprit. Always inspect thoroughly before making a repair. Check drains to make sure they are free of dirt, silt, and debris.

This wraps up the first part of Common Low-slope Roof Problems. 

Thanks again to Jana J. Madsen (jana.madsen@buildingsmedia.com) the managing editor at Buildings magazine.   For more information about C.A.R.E., visit (www.gaf.com) or e-mail (care@gaf.com).

Next week I’ll post-up the rest of this great article.

Want more information? Trying to understand the costs associated with replacing a roof?  Call, email, post to Facebook, or tweet to us. No Fee, No Obligation, Just help for you.

Don’t want to talk to anyone and just want a quick, satellite photograph measurement to help estimate the cost for your roof?  Order the Quick Report

If you have a specific roof issue and can send us a photo via email, Facebook, or Twitter, we will do our best to advise you on the specific issue.

 

8
Nov

Roof mold – Is it dangerous?

Black "roof mold" on shingles

Black “roof mold” on shingles

Roof Mold.  What is it and is it dangerous?

Is it algae, moss, lichens, fungi, or possible deadly black mold?   We have all heard about deadly black mold growing in homes.  But rest assured, that roof mold is not that rare deadly black mold.

But on houses receiving the right conditions of shade and moisture/humidity, growth of things like algae, moss, or fungi will grow.  In areas with high humidity or frequent rainfall, ensure that your roof is exposed to as much sunlight as possible.

Roof mold or other growths may be merely unsightly; but in more severe cases, can begin destroying shingles.

With algae and some fungal growth, the extent of the damage may only be shingle discoloration.  In warm, humid conditions, certain airborne algae can grow on shingles, leaving “roof mold” that is black or dark-green stains.

Moss or lichens growing on a roof are more likely to hold moisture against the shingles, which can accelerate damage.  Furthermore, if left untreated, their roots or growth structures will eventually penetrate and shorten the life of roof shingles.

Another likely source of damage is the cleaning methods used to combat roof mold or algal growth.

Pressure washing and harsh chemicals can cause rapid granule loss or other shingle degradation.   As is the case with algal treatment, the removal methods for roof mold may cause more damage than the growth itself.  But that does not mean you just leave the growth.  Take preventative measures to combat these growths since roof mold can be destructive.

Tree damage is also a leading cause of of the discoloration attributed to roof mold.

Roof damage from tree branches are a major contributor to needed roof repair or replacement.  Branches that rub against the roof cause granule loss and in some cases cut through the shingles or pull them out of place.  This loss of granule will change the color of the shingles as they are removed.

Unsightly “roof mold” may be the least of your concerns if branches are not trimmed when they come in contact with the roof.  During a storm, heavy winds may cause branches to break off and land on your roof causing major damage to the shingles and decking.

Trim away any overhanging tree branches and maintain your gutters and downspouts so that rainfall will drain quickly.

Confused or want more information?

Trying to understand the costs associated with replacing a roof?  Call, email, post to Facebook, or tweet to us.  No Fee, No Obligation, Just help for you.

Don’t want to talk to anyone and just want a quick, satellite photograph measurement to help estimate the cost for your roof?  Order the Quick Report

If you have a specific roof issue and can send us a photo via email, Facebook, or Twitter, we will do our best to advise you on the specific issue.

24
Oct

How do I know when to replace my roof? Danger signs for a roof. – part two

Roof problems that help answer the question, “How do I know when to replace my roof?” part two

Last week we pointed out that the guys over at GAF, who manufacture roofing materials, posted a really good set of photos to help you determine if you have red flags that need to be carefully examined.   They call them Key Danger Signals of a Failing Roof?

Let’s look at the other danger signs that likely point to a roof replacement need.  But remember that not every type of roof damage means you have to replace your roof.  You might be able to patch it and then prepare and plan to have it replaced in the near future.

But be on the lookout for the issues below to help answer the question, “How do I know when to replace my roof?”

Stains on Interior Ceilings and Walls or Mold and Mildew Growth

Possible cause: Leaking water supply or drain line OR inadequate, faulty shingle underlayment which allows leakage.  Mold could also be caused by inadequate ventilation which traps moisture.

 

Stains leading to roof replacement

Stains indicating water penetration

Exterior Decay, Sheathing, and/or Siding

Possible cause: Poor attic ventilation.  If the exterior of your home looks like this picture you have a real problem.  Does this answer the question, “when to replace my roof?”  Not yet.  But you need to figure out what is causing this problem. You might have a leak which is slowly eating away at your sheathing or siding.

 

exterior damage indicating roof replacement need

Siding damage

Missing, Cracked, or Curled Shingles

Possible cause: Shingles have reached the end of their useful life OR a major storm tore up the roof.  Sometimes your shingles have just reached their end of life and you need to replace the roof.  If you have 20 year shingles, have had your roof on for 25 years, and it looks like this photo you can answer the question, “How do I know when to replace my roof?” in by nodding your head repeating after me, “Yes.  I need a roof replacement.”

 


singles destroyed indicating roof replacement  need

Major damage to shingles

 

Dark, “dirty-looking” areas

Possible cause: Loss of granules due to age of shingles.  This one is tough.  Your singles might have simple been worn down over time or you might have mold growing on your roof.  It is important to take a closer look.  Do not jump to roof replacement mode just because you have a few worn shingles.  In this photo, the granules have definitely been worn away.  This is a warning sign that a roof replacement is in your future.  But does this answer the question “when to replace my roof?”  Not exactly but it is a warning sign.  At some point these shingles will fail but you still might have a few years if the rest of the roof is in fair shape.

shingles  missing granules indicating time to replace roof

Shingles with missing granules

Confused or want more information? Trying to understand the costs associated with replacing a roof?  Call, email, post to Facebook, or tweet to us.  No Fee, No Obligation, Just help for you.

Don’t want to talk to anyone and just want a quick, satellite photograph measurement to help estimate the cost for your roof?  Order the Quick Report

If you have a specific roof issue and can send us a photo via email, Facebook, or Twitter, we will do our best to advise you on the specific issue.