December, 2006

In Depth: Ventilation Products

Controlling Air and Moisture Infiltration has gained a higher profile as customers realize the danger posed by mold and rot.  

By Craig A. Shutt

Ventilation products have long been given lip service by many builders and contractors, but that has changed in recent years. As energy costs rise and Mother Nature makes moisture control a higher priority, proper air- and moisture-control products require a closer look.

“The building-science community in particular has taken an interest in finding better ways to build homes and handle moisture problems,” says Tom Fallon, vice president of Cosella-Dörken in Beamsville, Ontario, Canada, makers of the Delta-Dry polyethylene sheeting that dries and drains sheathing beneath brick. “Builders are a lot more sensitive to these needs now.”

Gary Urbanski, national sales and marketing manager at Trimline Building Products in Minneapolis, agrees that ventilation and moisture-control products are given more consideration today. “We’re finding builders and contractors are more understanding of the need to ensure there is proper ventilation, and they’re trying to educate themselves about the products,” he says. “In the past, it was just a matter of putting something in as they always did. Now, there’s more focus on determining the right way to ventilate each space and examining the products that are available and what each will do.”

In part, that heightened awareness has been driven by home buyers and remodeling customers, who have questions of their own, says Donnie Anderson, director of wholesale sales at Air Vent Inc. in Dallas. “Attic ventilation has become more important to consumers because they have become better educated about the need,” he says. “As they become more aware and ask questions, it creates a chain reaction through the rest of the channel.”

Four Key Factors

There are various factors driving those concerns and the higher interest in ventilation and moisture-control products of all types, he notes. The four key drivers are:

Energy efficiency.

As energy and gasoline prices have risen in recent years, homeowners realize they need to bring down their consumption. “The public has become more energy conscious,” says Anderson. “People are understanding how ventilation can help decrease heat build-up and air-conditioning costs.”

They also see the need to provide more control over air penetration, says Arturo Horta, roofing systems market manager for Tyvek Atticwrap at DuPont Building Innovations in Wilmington, Del. “We are seeing an increasing demand for products that help builders achieve a more air-tight, energy-efficient home,” he says. “One of the most popular trends nowadays is to use products that aim to achieve a ‘sealed building envelope.’” House-wraps are a fast-growing category in that regard, he adds, because “they play a double function, since they work as both water and air barriers.”

Steve Easley, president of Building Media Inc. and an LBM Journal contributing writer, agrees that attic-wrap products are becoming popular because they allow moisture to wick away without taking heat with it, as air vents can do.”You want the heated air to remain but the moisture to leave,” he says. These products can save 10-20% on a home’s energy bill while reducing attic temperatures by 20%, he estimates.

Ensuring that moisture can leave a home has become more of a concern as homes have become better insulated and protected against air infiltration—which also prevents moisture from leaving. “The concern is that as we make the buildings tighter for energy conservation, we might be increasing the risk of moisture problems,” says Horta. “We need to ‘build tight and ventilate right.’ If we focus exclusively on energy, and we forget about moisture and indoor air-quality management, we increase the risk of having moisture-related problems.”

Mold.

Media reports have homeowners dreading the specter of a devastating mold build-up behind walls or other low-visibility locations where moisture has penetrated. “There has been an overall drive in residential building to ensure that the proper products are  installed to allow for drainage and moisture control,” says Fallon. “It’s becoming a bigger and bigger item, and the number-one issue is mold.”

Most homeowners are well aware of cases where extreme mold growth and the resulting extreme reactions have caused homes to become uninhabitable. “Mold concerns are definitely out there, but there are few actual cases of it being an issue,” says Urbanski. “But it’s a concern because it is a possibility that could happen.”

Simply installing ventilation products won’t alleviate the problems, stresses Mike Graham, vice president of Smart Vent in Pitman, N.J., which makes foundation flood vents. “Unless the vents are positioned properly near corners, you don’t get the proper circulation, which can lead to mold and mildew problems,” he explains. This can be a particular concern where manual vents control ventilation, as in crawl spaces. Homeowners close the vents in winter to prevent freezing air from entering, but they neglect to reopen them in the spring when natural ventilation is needed with warmer, moister air circulating.

Flooding.

Last year’s hurricanes and other flood conditions around the country have led to more interest in flood-control devices—particularly among insurance officials, and that ensures they also become of interest to builders, contractors and homeowners. FEMA, code officials and flood insurers are enforcing flood rules that require openings to let water flow into a foundation and back out again to relieve pressure against foundation walls, explains Graham.

“The number-one thing that code officials look for is the use of vents for flood control,” he says. “But many vents are sealed in the winter and forgotten, and that ends up putting pressure on the foundation when the flood comes.” Flood insurance has increased dramatically for structures without vents, he says, sometimes requiring premiums as high as five times that of structures with vents. “Homeowners don’t always see the value of putting in these vents, but they’re being forced to do it due to insurance premiums,” The interest is growing across the country, he notes, as officials in flood plains clamp down. Floods can create not only pressure problems on a foundation but also can lead to mold and other damage if ventilation is not sufficient.

“Leaky Condo Syndrome.”

A major concern with the potential for building-envelope failures arose with structures in Vancouver, British Columbia, and it has since spread to other areas, including markets in the United States, explains Cosella-Dörken’s Fallon. In these projects, “catastrophic failure of the building envelope” occurred when water entered the structure and created rot, rust, decay and mold, according to a research report by the Canadian Mortgaging & Housing Corp., the national housing agency.

The report indicated that as many as 65,000 dwellings in the province have the potential for this failure. The problem has been exacerbated by later reselling of the units without disclosure to the buyer, who may not have been aware of the problem.

Part of the problem stems from new types of cladding systems that are becoming popular, such as stone finishes and man-made stones, Fallon explains. Through a process called solar-driven moisture vapor, the materials warm up when the sun comes out, pulling the moisture inward through the backside of the brick into the exterior wall cavity. Media reports on these projects have increased awareness and made many developers focus more attention on ventilation.

Various Ventilation Types

With increased awareness of ventilation issues, the builder’s goal is to find the proper type of ventilation for the application. Among the most common types of roof ventilation are ridge vents along the home’s peak, power fans, static vents and gable-end vents.

“Not all ventilation products perform equally, and some are made for different applications,” explains Air Vent’s Anderson. “Not every home will be able to use the same type of ventilation.” Hip roofs, for instance, don’t always provide enough horizontal linear footage to install ridge vents, so they need another type.

For many applications, builders and remodelers are using more ridge vents, marketers say. “Ridge vents have become the most popular,” says Air Vent’s Anderson. Air Vent makes a wide range of ventilation products, he notes, allowing the company to compare and contrast options for customers. Among ridge vents’ benefits is the ability to run the entire length of the home’s roof peak, which avoids dead spots where air can’t circulate. Since the vents have a low profile, they don’t affect the home’s curb appeal, either. “Continuous ridge vents provide a better approach,” Easley agrees. “When other types are used, there typically aren’t enough of them to ventilate adequately.”

A change in products from a “stick” type of ventilation unit to a roll has improved their popularity, says Urbanski. “That’s had a big impact on their use, because that type is easier to handle and looks great when installed. They really provide the best and most efficient way to ventilate a roof because they provide continuous ventilation.”

But the roof peak isn’t the only location requiring ventilation, stresses Urbanski. “We have to help the builders and homeowners understand that ventilation is a system, and that roof vents have to work with soffit vents on the lower end of the roof too,” he notes. Since Trimline doesn’t sell soffit vents, that effort requires the company to work with siding companies to ensure the systems work. “It’s an active process, and designers have to think about intake and exhaust together.”

DuPont’s Horta agrees. “We have to take a holistic approach in the design of buildings, since heat, air and moisture work together.” His company’s Sealed Attic System is designed to aid this process by creating an airtight attic that keeps moisture out while also allowing vapor to escape and managing heat with its reflective surface.

Cosella-Dörken also is trying to take a system approach to moisture control, building on its long-time applications below grade with the introduction of its Delta-Dry polyethylene sheeting to dry and drain sheathing. Introduced in June, the product has been received well in Florida and the Northwest, which have particular humidity problems, Fallon says. The company is planning to build on those products with the introduction of roof underlayments by next summer. “Our goal is to create an entire top-to-bottom system of protection,” he says.

More Education Needed

Although visibility and awareness are growing, marketers say that much of the education process remains. “Builders sometimes use what they’re familiar with and don’t always see the value in new products,” says Smart Vent’s Graham. They fear callbacks or other problems will offset any benefits they may achieve overall. In some cases, though, they’re being forced to use the flood vents due to increased insurance premiums, making them an easier sell, he notes.

Fallon agrees that housing officials are helping the trend. “It can be a complicated process to introduce new products to the market, but in the Northwest, we’ve had success in the apartment-conversion community,” he says, particularly due to the leaky-condo issue. “They are very quickly picking up on our products to help prevent this.”

Indeed, interest often varies by market, with new ideas gaining steam as builders see what their competitors are doing. Colorado, for instance, uses a lot of static vents rather than ridge vents, says Anderson. “Some markets just fall back on tradition.” Adds Urbanski, “We have to continually be talking with builders and contractors to ensure they understand the issues and that we are explaining how to use the products to meet their needs and educating them about the benefits of ridge vents.”

To that end, most of the companies employ point-of-purchase materials in the form of header cards, posters and other pieces that can explain the benefits in the store. Cosella-Dörken will soon be introducing palletized displays carrying rolls of its Delta-Dry along with a dispenser. It also will include tear-away pads with information to be read later. Those displays will be available through the company’s distributor, Huttig Building Products. The company also is offering sales packages that include samples and CDs with graphics.

Smart Vent’s program includes training sessions to explain benefits, while Air Vent offers educational seminars and brochures. “Consumers need something that they can take home to consider,” says Anderson. That’s particularly true with premium products such as the company’s new solar-powered power fan. “We’re seeing more interest in it because it doesn’t require electricity.”

The education process is enhanced by a wide range of other influences—including government agencies, insurance companies and building inspectors—that are emphasizing the need for good ventilation and moisture-control systems in homes. As those efforts expand and homeowners understand the dangers if they neglect these products, these often overlooked or underestimated items may become more prominent on take-off lists.

CRAIG A. SHUTT, senior contributing editor of the magazine, has nearly 30 years experience covering the LBM industry.