Foundations

The extended drought across the Southeast is causing home foundations to sag and crack, sometimes causing loud pops that the homeowners can hear.

Clay soils that have sustained homes for decades are drying and shrinking, causing sinking foundations, cracking walls and sticking doors. Other effects from excessive drought include collapsed concrete slabs and chimneys that have pulled away from houses.

Contractors are reporting their call volumes up 200 percent. "We have people reporting right now that they are literally hearing the brick crack," said Mark Beckham, owner of foundation repair service Ram Jack of Charlotte. "It holds on as long as it can, then lets go."

The problem can occur anywhere there is a layer of clay beneath a home’s footing. Contractors say they are seeing problems with dwellings of all ages, and that houses on slabs as well as those built over crawl spaces are at risk.

Foundation pouring began this week for the new Adams County Correctional Center in Mississippi. Flintco, Inc. is the general contractor on the project. Como, Mississippi-based Cross Concrete is the concrete contractor.

Many homes in southern Ohio have flooded basements due to cracked concrete foundations caused by the intense summer drought and heavy fall rains, local media reports.

"The ground’s so dry everything has pulled away from the house," said one of the residents whose basement flooded last Tuesday. "There's no expansion in the foundations, nowhere for the concrete to stretch to and that's why you end up with the cracks, that's why the foundations have been cracking."

The falling rain has nowhere to go but through the cracks and into basements, leaving behind a messy and costly cleanup.

Construction of new homes fell in August to the slowest pace in 12 years as troubles in the housing industry continued to intensify.

The Commerce Department reported Wednesday that construction of new homes fell by 2.6 percent in August to a seasonally adjusted annual rate of 1.331 million units. The housing industry is experiencing its steepest downturn in 16 years, with analysts forecasting weak prices and further declines in sales for months to come, given rising mortgage defaults, which are dumping even more homes on an already glutted market.

On Tuesday, the National Association of Home Builders reported that its index of builder confidence fell in September to 20, tying the lowest level on record.

A Windsor, California-based foundation contractor is finding success in a new market segment he believes offers major opportunity for much of the industry – building foundations for solar arrays.

Gateway Construction & Concrete is now building its sixth solar panel foundation, of which have occurred in 2007, in partnership with a developer of solar arrays that discovered it could not build its own foundations because of the precision required.

“They have a drilling company that was going to try to set the foundations,” says Ron Bryant, president of Gateway. “But doing that part and getting within the required tolerance was over their head. They could drill a hole, but they didn’t have the ability or the knowledge to do the layout, set it up or anything.”

Solar array foundations cannot vary more than an inch within a 1,000-foot foundation.

Gateway is working with two major providers of solar arrays – Ukiah-based Real Goods Solar and Navoto-based SPG Solar. Bryant said Gateway had tried to move into general building in recent years, but abandoned it because the projects were not as lucrative as consistent foundation work. Solar array foundations, he says, provide a strong complement to traditional foundation work.

“They’re set in drill piers by the soil engineers as to diameter, depth and whether it needs steel reinforcement or not,” Bryant says. “It differs from compression-type piers and foundations you would have on a house to hold things down in place. These are friction footings that hold it down to protect from the wind updraft, because these solar panels will act like a giant wing, so it’s got to hold it to the ground and hold it steady.”

Palladon Ventures Ltd. has begun pouring the concrete foundation for power substation facilities at the Iron Mountain project near Cedar City, Utah.

On Tuesday, Palladon began pouring concrete foundations for a four-foot-thick support pad measuring 22 feet by 15.5 feet. This concrete pad will support the new 51-ton transformer currently in transit to the site. The transformer and substation installation is scheduled for September and October with all electrical feed systems to be operational by the end of 2007.

The power infrastructure at Iron Mountain will consist of a large electrical substation and switching unit connecting future Iron Mountain plant facilities to Cedar City's 138 kV main power line which feeds from two directions. The power substation project includes the pouring of concrete foundations, construction of control housing, installation of switching gear and transformer and the installation of transmission lines and power poles. The design of the substation will allow for distribution of power from several sources, ensuring a stable power supply free of surges and interruptions and a substation large enough for future expansion.

Two leading industry advocates for flowable fill and self-consolidating concrete last week touted the two materials for use in the repair of the 9/11-damaged lower Manhattan rail transit hub.

Phil Kresge, mid-Atlantic field promoter for the National Ready-Mix Concrete Association, was joined by Carmine Attanasio, executive director of the New York City Concrete Promotion Council, in a presentation to Phoenix Constructors – a consortium of four contractors who have won the contract to do the transit hub rebuild.

Kresge and Attanasio say they did not secure a commitment from Phoenix Constructors to spec either material, but believe there was strong interest, and the two are now following up to secure the specification.

“The beauty of having that group of people is that some of the folks were coming from other companies who had used these materials before,” Kresge said. “One of the gentlemen who had used self-consolidating concrete said he was satisfied with it, so he backed up what we said.”

Neither NRMCA nor NYCCPC are representing a particular supplier of either material, but Kresge said they will engage in vigorous followup as a matter of industry promotion. He also believes some of New York’s previous experience will help the effort succeed.

“It worked with the Second Ave. subway project,” Kresge said. “We pretty much did the same presentation there, and as a result of our presentation they have placed in the bid documents a specification for flowable fill for backhoe.”

Phoenix Constructors consists of four major general contractors, Fluor Enterprises, Bovis Lend Lease, Slattery Skanska and Granite Halmar Construction Company. If the group specifies flowable fill for the project, it would require approximately 5,000 cubic yards.

An industrial-size wharf to be used for a nickel-mining operation in Raglan, Quebec is being constructed miles away in the form of concrete caissons, which will then be shipped to the location of parent company Xstrata for installation at the mine.

The project contractor is Beaver Marine Ltd., which expects the wharf to be transported in August.

The concrete for the third of three cement caissons is being poured this week. When completed, the sectioned wharf will be loaded onto a large semi-submersible ship and transported to the mine’s Deception Bay loading facility.

The caissons are compartmentalized, hollow boxes, 30 by 16 meters and 22 meters high, ballasted with water so they stay afloat. They are submerged 14 meters below the surface of the Strait of Canso, with the remaining seven meters visible above the water.

Beaver Marine Ltd. used the same process to construct a wharf for Nova Scotia Power’s Point Tupper facility about two years ago. Five cement caissons were built in Mulgrave and floated across the Strait to Point Tupper.