Rooftop Decks Add Outdoor Living Space to Sacramento Town Homes

The three-story homes are built on narrow lots without a backyard, so the decision was made to offer a roof deck package to provide an area to enjoy the outdoors. Photo: The Grupe Company

More and more, builders, architects and designers are looking to the rooftop as an area for usable living space — especially in urban areas, where lots are narrow. For a new town home development in Sacramento, the idea to add rooftop decks emerged late in the design process, but it’s proved so popular the builders are not only glad they made the change — they are considering making it a standard feature in future projects.

Designed by Ellis Architects and built by The Grupe Company, the neighborhood is known as 20 PQR. “The project fronts on 20th street in mid-town Sacramento and runs from P Street down to R Street,” notes Ron Rugani, vice president and purchasing manager for Grupe. “Q Street runs down the middle of the project, so that’s how we came up with the name 20 PQR.”

The 32 town homes are arranged in four groups of eight. The three-story residences have two different floor plans, one with 1,750 square feet and the other 1,850 square feet. “It’s an interesting concept,” Rugani says. “They are really considered single-family homes. They have their own lot, and they are detached from the next unit. There is a 6-inch space between the units, and they don’t share a common wall. However, the way we trim out that space, on the top and sides, you would view the eight units as one building, but they are actually eight individual single-family detached town homes.”

The narrow lots left no room for a yard, so that’s what inspired the idea to create usable outdoor space on the roof. “If you can imagine the urban setting — the fronts of these units are right on the city sidewalk. All of the units have two-car garages in the back and are accessible through a common alley. But there is no outdoor living space, and so that’s essentially what’s driving these roof decks,” Rugani says. “The backyard is where people are going to have outdoor living in a typical single-family home, and the rooftop deck is where they are going to have outdoor living in a town-home setting.”

The low-slope roofs were designed with internal drains and parapet walls. A GAF TPO roof system was specified. When the decision was made to add the rooftop living area, Ellis Architects recommended installing rubber roof deck tiles from sofSURFACES on top of the TPO roof. “The architect steered us in this direction because they liked the product,” notes Rugani. “After the roofer installs his regular TPO roof, it gets inspected to make sure there are no leaks before the roof deck tiles are installed. It’s a really unique product. It allows water to go through to the TPO roof for drainage. It has an excellent warranty, and so we have a long-term warranty for the entire roof system.”

Applying the Roof System

The TPO roof system was installed by PetersenDean Roofing and Solar, Fremont, California. “We are a roofing subcontractor for Grupe on several projects in the Northern California area,” says Mark Vogel, president of PetersenDean’s Builder Division. “We have built a great relationship with them over the years.”

Photo: sofSURFACES

There was approximately 900 square feet of roof area on each structure. PetersenDean crews mechanically attached the 60-mil GAF EverGuard TPO membrane over quarter-inch Georgia-Pacific DensDeck roof board and rigid insulation. “It is a flat roof with low slope conditions,” Vogel says. “This is absolutely a great system for this type of work.”

The parapet walls greatly simplified the safety plan, but safety is never taken for granted, according to Vogel. “We have 22 safety engineers nationwide, with 14 in California,” he says. “Safety is our biggest concern, and we invest to ensure we send everyone home at night. Our workers are considered our most valuable asset and we strive to maintain a world-class safety culture. Having a skilled and talented workforce that truly cares about safety drives everything that we do.”

Everything on the project went smoothly, notes Vogel. “It was not tough to coordinate the work with the other trades,” he says “It is what we do, and there is no one better. We are a full-service roofing contractor and solar power installer. We handle estimating, design, permitting, and installation for roofing and solar roofing systems for all our clients and this project is a great example of this.”

Installing the Roof Tiles

The deck area on each roof encompassed approximately 700 square feet. The interlocking duraSTRONG tiles are made from recycled rubber and are ideal for outdoor rooftops, walkways and patio projects, notes Chris Chartrand, director of marketing for sofSURFACES. “This space was ideal for our product as the rooftops are flat and have proper slope with a contained edge,” Chartrand says. “The design allows for efficient drainage of surface water.”

The low-slope roofs were covered with a TPO roof system manufactured by GAF, and the deck areas were topped with interlocking rubber paving tiles from sofSURFACES. Photo: sofSURFACES

The tiles were applied by a manufacturer-certified installer, Leonard’s Construction of Fontana, California. “Coordinating delivery and installation of our product within Grupe’s required timelines was a fairly easy task, as we were the last phase of the project,” notes Chartrand.

Paulo Carrillo, installation supervisor, typically installs the product in gyms and playground areas, but recently he’s found himself doing a lot of work on terraces and rooftops. After the roof system was completed on the homes at 20 PQR, a second sheet of TPO membrane was installed as a protective barrier. “We chalked our lines on that,” Carrillo notes. “We measure out the whole rooftop and chalk it off into a 2-foot-by-2-foot grid. Every other square is a keystone — those are the tiles that we put in first that hold everything in line.”

After the keystones are glued in place, the crews cut pieces to fit along the perimeter and then begin to add tiles in strategic lines. After those tiles cure, tiles are laid in opposite directions, both horizontally and diagonally. “We do it step by step,” Carrillo notes. “When we put the final squares in at the end, they are all interlocked together. After we do the final step, we glue each seam, so everything is 100 percent glued.”

The tiles all interlock, and compression allows for expansion and contraction. “Every tile is 24-1/8 inches, but they go into a 24-inch space,” Carrillo explains. “They are all compressed. With any perimeter cuts, we add another 1/8 of an inch to get our compression.”

Stacking the Deck

According to Rugani, Phase 1 and Phase 2 of the 20 PQR have been completed and are sold out, while Phase 3 and Phase 4 are currently under construction.

The interlocking duraSTRONG tiles are made from recycled rubber. They are designed for use on rooftops, walkways and patio projects, as well as gyms and playground areas. Photo: sofSURFACES

Originally the roof deck area was offered as an option, but it’s proved so desirable all of the units in the last phase are being built with decks. “It’s been an interesting dynamic,” says Rugani. “When we started, we weren’t sure how many people would want this option. For the first phase, we had to spec those, so, we said, let’s build six of the eight with the roof deck. It started to gain in popularity, and the price didn’t seem to be an issue, so in the last phase, we said, let’s build them all. It’s become very popular.”

Based on the success of the roof decks at 20 PQR, Grupe is exploring roof deck options for other projects in development. “We are building a mid-rise apartment complex just a few blocks away, and we said from the get-go in that project that we are going to have some type of roof deck for outdoor living space for the tenants,” Rugani says. “For that project we did develop a rooftop deck, and I believe that is going to be the M.O. moving forward in any project we do. Otherwise there might be no place for tenants to gather on site and have some outdoor living space. It makes perfect sense to go to the roof. So, yes, I see this as a trend, especially in urban settings.”

In the 20 PQR project, the homes were not originally designed with roof decks, and the decision made to add them later meant a lot of extra time and work for engineers and architects. “A lot of people might walk away from that and say it is too much work,” Rugani says. “We said, this is something we need to do, and it’s going to benefit the people who buy it. We were happy in the end that we spent the time and effort to do it.”

TEAM

Architect: Ellis Architects, Sacramento, California, www.ellis-architects.com
General Contractor: The Grupe Company, Stockton, California, www.grupe.com
Roof System Installer: PetersenDean Inc., Fremont, California, www.petersendean.com
Rubber Paving Tile Installer: Leonard’s Construction, Fontana, California

MATERIALS

Rubber Paving Tiles: duraSTRONG, sofSURFACES, Petrolia, Ontario, Canada, www.sofsurfaces.com
Roof Membrane: 60-mil TPO, GAF, www.GAF.com
Cover Board: DensDeck, Georgia-Pacific, www.densdeck.com

Orlando Airport Project Necessitates Custom Fabrication, Precise Installation

 

Work on the first phase of the Orlando International Airport expansion project includes the South Airport Intermodal Terminal Facility and APM Complex, which features a standing seam metal roof

Architectural Sheet Metal Inc. has been in servicing the Orlando area for more than 23 years, specializing in commercial metal roofs and wall systems, primarily new construction. When Matthew Leonard, the company’s vice president, found out that the Orlando International Airport was proposing a new terminal project with a metal roof, he jumped at the chance to submit a bid.

He wanted to land the job because it would be the largest project the company has ever tackled, and one of its most prominent. He also wanted it for another reason—he knew he’d see it every time he drove to the airport. “For many years now, we’ve specialized in standing seam metal roofs. It’s our bread and butter,” he says. “We’ve done lots of schools, government building, military bases. It’s just something we enjoy doing. When this project came around, right here in our backyard, we knew we wanted to take it on. It’s larger than anything we’ve ever done, but it’s our specialty.”

The South Airport Intermodal Terminal Facility and APM Complex is a new construction project that coordinates mass transit for the airport, including regional rail systems and the Automated People Mover (APM). It’s part of the first phase of an ambitious $2 billion plan to almost double the size of the airport.

Architectural Sheet Metal installed the Berridge standing seam metal roof system, as well as internal aluminum gutters and a custom-fabricated aluminum bullnose that runs along the perimeter of the roof

The building encompasses approximately 200,000 square feet, and the structure is primarily covered with a standing seam metal roof. The scope of work for Architectural Sheet Metal included installing the metal roof system and internal aluminum gutters. It also included custom fabrication and installation of an aluminum bullnose that runs along the perimeter of the roof. “Every roof is radiused, and some sections have compound double raiduses,” Leonard notes. “The trickiest part of the project is probably the bullnose because all of the gable ends of the roof are radiused, and the large bullnose has to be welded on in 30-foot sections.”

Another tricky thing about the project is that the work was divided into two different contracts with two different construction managers. On one side of the building, which houses the monorail and parking garage, the project is overseen by Hensel Phelps, and on the other side, which handles the train lines, the construction is overseen by a Turner-Kiewit joint venture. The dividing point is a building expansion joint that runs across the middle of the roof. “We’re one of very few subcontractors out here that has a contract with both of the construction managers,” Leonard says. “They both have their own agendas, their own timelines, and their own completion dates, and it was a delicate balancing act working with the two of them.”

Installing the Roof

The roof system was designed to unify the elements of the structure and tie the building together. Some sections of the roof cover the building, while others serve as canopies, so there are two types of metal deck on the building. “The area we call the spine has a 3-inch-thick acoustical deck,” Leonard explains. “That was interesting because before we could put our 6 inches of polyiso on, we had to install batten insulation in the flutes. The acoustical decking is perforated, so you can see through it. That’s a little different, when you’re so high up. It spooked the guys at first to be able to see right through it.”

Crews dried in the entire roof with a waterproofing underlayment from MFM Building Products specifically designed for high-temperature applications.

The other sections were comprised of standard type B metal deck. Sections covering the interior were insulated, while canopy sections were covered with 5/8-inch DensDeck from Georgia-Pacific.

Crews from Architectural Sheet Metal dried in the entire roof with a peel-and-stick waterproofing underlayment from MFM Building Products specifically designed for high-temperature applications, MFM Ultra-HT. “It’s easy to install,” notes Leonard. “That’s our go-to underlayment for metal projects.”

After the underlayment was applied, the welded aluminum gutters were installed. “The longest piece was 78 feet,” says Leonard. “We fabricated the sections, water-tested them and shipped them out. We used a crane to lift them to the roof.”

The roof system was supplied by Berridge Manufacturing, and the 24-gauge galvalume metal panels were roll formed at the site. “Berridge has a ZEE-Lock double-lock standing seam panel,” Leonard says. “We own one of their portable roll formers, and we have it on site here. We pick it up with a crane, and lift it up to the edge of the roof, and we actually roll form our largest panels straight out to the roof. The guys just catch the panels as they come out of the roll former.”

Metal roof panels were roll formed at the site. For most roof sections, the roll former was hoisted by a crane, to the edge of the roof, and crew members stacked the panels as they come out of the roll former.

Panels were stacked in piles of 10 for installation. There were 12 different roof surfaces, so as the roll forming crew moved along, other crews would start installing the panels. “Every stack was tied down with strapping to ensure that it wasn’t susceptible to wind,” Leonard points out. “With a hurricane in the forecast, we were very careful about that.”

The panels in the spine area had a tighter radius, so those panels were formed on the ground using separate curving machine. Lining up the panels perfectly was critical. “With a radiused roof, it’s sometimes harder to find things to measure off to ensure your panels are straight. This panel is a left-to-right system. It’s a male-female overlay with a continuous clip that Berridge manufactures. The panels are hand-crimped together, and then you do the first and second stage of the double-lock panels with an electric seamer. You just turn it on and it goes up and over.”

Details, Details

Fall protection posts were installed during the framing process, which helped with safety planning but posed problems when it came to detailing. “It’s nice to have permanent fall protection points to tie into, as everyone had to be 100 percent tied off, but there are close to 200 fall protection posts on the project that we had to cut around and flash,” Leonard says. “I’ve never seen so many posts on a roof like that.”

The aluminum bullnose was constructed after precise measurements were taken at the site. After they were custom painted to match the roof, the 30-foot sections were lifted into place and installed.

Because the posts were tied into the structural steel and couldn’t be moved, the company designed and manufactured a welded aluminum flashing detail to ensure they all looked the same no matter where they landed in the panel profile. “We set up a welded aluminum flashing that should last forever, and it’s welded, so it shouldn’t leak. We try to go above and beyond in our flashing details.”

Leonard points to his company’s fabrication experience as a key to its strength. “We try to be more than just a roofing company,” he says. “We try to be a custom metal fabrication company that fabricates the panels to precise specifications determined by the site. We custom fabricate metal and then, as roofers, we install it. We like to have that double whammy. Not many people have that ability to do both.”

The company’s expertise came in handy on the bullnose. “The bullnose was originally bid as 22-gauge metal,” he says. “We looked at it and we didn’t like it. It’s a large, 9-inch radius, and we felt the thin, light-gauge metal would shake in the wind. Every 10 feet would be a lap joint with caulk, which would be susceptible to wind damage. We came up with the idea of using a welded piece of .080 aluminum. Once it was approved, we purchased a 100-ton press brake with a custom die to fabricate this bullnose.”

The bullnose was constructed from precise measurements taken at the site. “We took the radius off of the building and created jigs in our warehouse,” Leonard explains. “We welded pieces together in 30-foot sections, and we shipped them to a local painter who coated them with baked-on Kynar to match the roof.”

The bullnose was designed to hook into the gutter strap and wrap around onto the fascia, where it is screwed into the framing. In areas where there is no gutter, sections of the bullnose are equipped with a larger flange with an S-hook built into it to attach it to the roof. Corner pieces tie it all together.

Watching Out for Irma

Dealing with two different GCs was challenging, in part due to changes in the schedule. “Originally, we were supposed to finish one side first and then start the other side, but both phases of the project ended up starting around the same time,” says Leonard. “This doubled the manpower we needed on the job.”

Photos: Aerial Innovations

For changes like the bullnose, Architectural Sheet Metal had to make sure RFIs were submitted and approved by both sides. “Sometimes it was hard to keep track of who we submitted it to, but it worked to our benefit at times. Once it was approved by one side, it was easily approved by the other.”

The schedule had the crews working in hurricane season, and precautions were taken to make sure the job site was prepared for high winds. “When Hurricane Irma was approaching, I checked every single weather update every day until it made landfall,” Leonard recalls. “It hit on a Monday, and a full week ahead of that we were cleaning the roofs and preparing the gutters. We removed all debris on the jobsite because any trash on the roof could clog the downspouts. We added more and more men to the process throughout the week, and we shut the jobsite down on Wednesday. We took all of the material we had, stacked it, bundled it together, and we were able to move it all inside the building. We were pretty well complete on the Hensel-Phelps side, and Turner Kiewit brought in 40-foot Conex boxes for us to put our material in and secure it. They tried really hard to make sure the jobsite was secure.”

As the storm progressed, it deviated from the projected path, and no one could be certain which direction the winds might be coming from. “We just had to start battening everything down,” Leonard recalls.

Photos: Architectural Sheet Metal Inc.

Stacks of panels on the roof that were not yet installed were strapped every 2 feet on center. The entire state was in emergency mode, making things difficult. “For four or five days before the storm even hit, we couldn’t find water, rope and extension cords. Grocery stores were running out of supplies. Gas stations were running out of gas.”

After the storm passed, Leonard breathed a sigh of relief. The roof wasn’t damaged. The panels that had already been installed were in great shape, and the uninstalled panels weren’t harmed.

Elements like the weather are beyond anyone’s control, and Leonard notes his company tries to control as many variables as it can. “We have full control over the actual fabrication of the material and the quality of it,” he says. “When I call something in, I talk to our guy who works with me. Our company oversees it. Every morning I stop by the shop and follow up on the process on the way to the job site. We install it. I can make sure everything is OK.”

The project is nearing completion, and Leonard can’t wait to finish a landmark project he’ll see every time he makes a trip to the airport. “You can’t miss it,” he says. “It’s huge.”

TEAM

Architect: HKS Architects, Orlando, Florida, HKSinc.com
General Contractors: Hensel Phelps, Greeley, Colorado, HenselPhelps.com; and a joint venture between Turner Construction, Orlando, Florida, Turnerconstruction.com, and Kiewit, Sunrise, Florida, Kiewit.com
Metal Roofing Contractor: Architectural Sheet Metal Inc., Orlando, Florida, ASMfl.com

MATERIALS

Standing Seam Metal Roof: Berridge Zee-Lock Double-Lock, Zinc-Cote, Berridge Manufacturing, Berridge.com
Underlayment: MFM Ultra-HT Wind & Water Seal, MFM Building Products, MFMbp.com
Cover Board: DensDeck, Georgia-Pacific, Buildgp.com

Georgia-Pacific Gypsum’s Durable Cover Board Outperforms High-density ISO in Puncture and Hail Testing

Third-party testing results confirm that Georgia-Pacific Gypsum’s DensDeck Prime Roof Boards display puncture and impact resistance, protecting thermoplastic roofing membranes better than high-density polyisocyanurate (HD ISO) cover boards.

All types of commercial roofing membranes are susceptible to everyday punctures from a variety of sources. Rigid objects with sharp edges like dropped tools; heavy equipment; winds which blow branches and debris onto roofs; and frequent foot traffic for general maintenance and repair can cause punctures at any time, explains Todd Kuykendall, director of marketing and product management, Georgia-Pacific Gypsum. “DensDeck Prime cover boards support membranes so they can resist puncture damage, allowing them to do their job as the front-line protection of the roof assembly against water intrusion.”

Thermoplastic membranes tested in assemblies with 1/4-inch DensDeck Prime boards underneath were 83 percent more puncture resistant than membranes with 1/2-inch HD ISO or with no cover board at all, based on average calculations.

Thermoplastic membranes tested in assemblies with 1/4-inch DensDeck Prime boards underneath were 83 percent more puncture resistant than membranes with 1/2-inch HD ISO or with no cover board at all, based on average calculations.

The independent ASTM D5635 puncture test results indicate that thermoplastic membranes do not puncture as easily when 1/4-inch DensDeck Prime Roof Boards are used as a cover board, as compared with HD ISO boards. Puncture-resistance testing conducted by Jim Koontz & Associates, July 21 to August 1, 2014, in its Hobbs, N.M. laboratory, according to ASTM D5635 standards. Assemblies included a base layer of 2 inches, 20-psi polyisocyanurate insulation; and configurations were covered with 45-mil thermoplastic polyolefin (TPO) or 48-mil polyvinyl chloride (PVC) membranes. The test method evaluates the maximum puncture load the samples can withstand, without allowing the passage of water when subjected to impact from a rigid object with sharp edges. Thermoplastic membranes tested in assemblies with 1/4-inch DensDeck Prime boards underneath were 83 percent more puncture resistant, on average, than membranes with 1/2-inch HD ISO or no cover board at all.

Durable and versatile DensDeck Prime roof boards can potentially save money for roofing contractors, building owners and facility managers by eliminating or reducing the need for costly repairs due to punctures during and after completion of the roof installation, Kuykendall adds, “In these puncture tests, HD ISO performed similar to no cover board at all, allowing thermoplastic membranes to puncture more easily.”

Thermoplastic membranes tested in assemblies with 1/4-inch DensDeck Prime boards underneath were 83 percent more puncture resistant than membranes with 1/2-inch HD ISO or with no cover board at all, based on average calculations.

In addition to puncture resistance testing, the independent company also conducted tests simulating the impact of hail in a variety of roofing scenarios—and the results were similar.

Performance of 1/4-inch DensDeck Prime roof board versus HD ISO or no cover board at 1.5- to 2.5-inch hail ball impacts. Assemblies in these tests with thermoplastic membranes and high-density ISO cover boards demonstrated 25 to 30 percent greater indentation than similar tests with DensDeck Prime roof boards.

Performance of 1/4-inch DensDeck Prime roof board versus HD ISO or no cover board at 1.5- to 2.5-inch hail ball impacts. Assemblies in these tests with thermoplastic membranes and high-density ISO cover boards demonstrated 25 to 30 percent greater indentation than similar tests with DensDeck Prime roof boards.

FM 4473 (using NBS— National Bureau of Standards—23 standards) hail test results indicate that DensDeck Prime boards offer key benefits against hail damage versus HD ISO products. Hail testing (or impact resistance testing of rigid roofing materials by impacting with freezer ice balls) conducted by Jim Koontz & Associates July 21 to August 1, 2014, in its Hobbs, N.M. laboratory, according to FM 4473 (using NBS 23 standards). Based on average results using 1.5- to 2.5-inch freezer ice balls. Assemblies included a base layer of 2-inch 20-psi polyisocyanurate insulation; and configurations were covered with 45-mil thermoplastic polyolefin (TPO) or 48-mil polyvinyl chloride (PVC) membranes.

  • Less likelihood of membrane damage — Assemblies with DensDeck Prime panels exhibited less indentation that stressed the membrane and can potentially result in membrane failure;
  • More resilience during hail events — Assemblies with DensDeck Prime panels withstood larger hail sizes that may cause cover board fractures.

Performance of 1/4-inch DensDeck Prime roof board versus HD ISO or no cover board at 1.5- to 2.5-inch hail ball impacts. Assemblies in these tests with thermoplastic membranes and high-density ISO cover boards demonstrated 25 to 30 percent greater indentation than similar tests with DensDeck Prime roof boards.

Georgia-Pacific Gypsum Redesigns DensDeck Website

With the goal of providing more information and resources, Georgia-Pacific Gypsum has redesigned its website dedicated to its favorite roof board—DensDeck.

The new DensDeck website has targeted information that lets busy professional fine just what they need to know, quickly and effortlessly. Roofing consultants, Architects, Specifiers, Building Owners/Facility Managers or Roofing Contractors can click unto their specific section to find relevant content targeted to the interests and needs of those construction professionals.

The site was also designed to provide the best visual content for tablets and smart phones, making it much more accessible for highly-mobile design and construction personnel.

Visitors can also now sign up for eBlasts, with the option of providing a profile which will allowing Georgia-Pacific Gypsum to provide just that eBlast content which they would be interested in to make their roofing related tasks easier.

DensDeck.com also offers videos, case studies, technical resources and more on topics made to facilitate the roofing process for professionals.