How to Build an Affordable Concrete Home, from Residential Concrete
Some contractors are discovering new possibilities in the affordable housing market, by Joe Nasvik
Custom-built homes are commonly gracing glossy magazine covers. That's because people in the U.S. have been in love with the idea of owning a large elegant home. For architects and designers, there is more opportunity to present interesting ideas and work with unusual concepts. But with the decline in the residential housing industry over the past year, large custom home building followed suit, as well as the affordable home building industry. However, there is greater interest today in concrete home construction in the more affordable price range on the part of a number of builders. This attention is largely focusing on sustainability, green building, disaster resistance, energy conservation, and safety.
What Influences Affordability?
There are many different ways to define what makes a house affordable in today's market. All homes are currently more affordable because of declining home and property values over the past couple of years. Labor and material costs have dropped some as well. In the end, however, the affordability of a house correlates to its size. Homes ranging from 1000 to 2000 square feet are more affordable than larger custom-built ones; though there is a trend toward smaller custom homes. In terms of building philosophy, some builders achieve lower prices by constructing several homes at the same time while others keep costs down by building one at a time.
Judging affordability by the selling price of a home is beginning to change as more attention is given to operating costs over time. The builders of concrete home systems tend to have a long-term view in mind.
Longer Range Issues
In some parts of the country, homeowner insurance is becoming a very significant part of home ownership. In the southeastern states, for example, insurance rates skyrocket for homes built close to the ocean or in hurricane-prone areas. Insurance for homes built to withstand high-wind forces can be quoted much lower rates depending on the state and the insurance company. The same can be true for fire-resistant homes. When a homeowner applies for homeowner insurance, the first question the insurance company asks is “what's it made of?”
Chuck Vance is the fortified program manager for the Institute for Business & Home Safety (IBHS) organization. It is a nonprofit entity, supported by more than 200 insurance companies, charged with researching and recommending better methods for building disaster-resistant homes and commercial construction. When disasters occur the IBHS investigates the effect on structures in an effort to develop better building methods. IBHS shares its findings with code authorities and works to improve building codes. It also administers a program called Fortified...for safer living, which certifies that a home is built to the standards of the program. The process includes inspections during construction to verify that all the requirements are followed. Vance says these homes currently must be built to withstand winds 20 mph higher than local minimum codes. The goal is to reduce the risk from all types of natural disasters, including wildfires, making homes safer in the process. It also increases their affordability because they don't have to be replaced due to the effects of high winds.
In an age of declining resources, the energy to heat and cool homes is becoming increasingly more costly—directly affecting the cost of ownership over time. Owners and renters want to live in more energy-efficient and cost-efficient housing.
It's often reported that building a concrete home can increase costs over wood construction from 5% to 15%. But some builders report that they are able to build more affordably than with wood. Here is how some are doing it.
Building Low-Income Homes in Miami
Steve Luria is an architect, designer, and the owner of Roomscapes, Miami, a 10-year-old design firm that specializes in interior spaces. Five years ago he formed the nonprofit Haven Economic Development organization to focus on low-income housing. Now he says this housing construction is 60% to 70% of his business. Homes average 2000 square feet, featuring 1600 square feet of living space, and sell for approximately $225,000.
Luria says that Haven Economic Development both designs and builds homes in order to maintain control of costs. The houses are designed with affordability in mind and not a lot of fluff. Designs are simple, bare bones, and yet spacious with open floor plans for the kitchen, dining area, and living room—thus requiring less wall construction. He adds that the footings, floors, and exterior walls are concrete. All the homes feature hip roofs with no gables for increased wind protection.
“We use insulating concrete forms (ICF) made by Reward Walls, Omaha, Neb., for the exterior walls,” says Luria. “These walls are a little more expensive than a standard wood-frame construction but there are important savings in other ways.” The R-value of the ICF walls is R-22 and with high energy efficiency and reduce air infiltration. The concrete walls can easily handle the 146-mph wind code requirements. Other construction details include asphalt shingles with high-wind ratings, impact-resistant windows, steel studs for interior wall construction, stucco finishes for exterior walls, wood trusses double strapped to the walls for increased wind protection, ceramic tile throughout, recycled composite wood for trim work, standard drywall with no wood paneling, and the careful sizing of air conditioning units. Significant dollars can be saved by sizing air conditioning systems for concrete rather than wood-frame homes.
Luria says they are also part of the IBHS Fortified...for safer living program and, depending on the location of their homes, it's possible for owners to qualify for insurance savings of up to 40%. If homes are purchased through the Miami-Dade Infill Housing Program, first time owners can qualify for up to $50,000 loan reductions.
To date, Haven Economic Development has completed 15 homes and is building 10 more.
Building Removable Form Walls
Jim Bassett and Mike Zeanchozk own a concrete foundation business in Elmora, Penn. About 3 ½ years ago, they decided to incorporate Matrix Concrete Construction to go aboveground, building concrete homes in Florida. They completed up to six houses a week until the market dried up. Now they are building concrete duplex housing close to the coastline in Gulfport and Bay St. Louis, Miss., where Hurricane Katrina hit. Bassett says their average unit is 1049 square feet with a 317-square-foot garage and a small porch, which sells for $250,000. Building features include 8-foot-high cast-in-place exterior concrete walls, concrete demising walls to the top of the roof, wood-frame interior walls, and wood truss roofs. Bassett says that Mississippi recently adopted Florida's wind code requirements, so their homes are built to resist 146-mph winds. He says that mass producing homes using Western Forms handset aluminum forms is one way they stay affordable.
In northern Florida, Ken Krantz, who has a structural concrete background, focused his concrete construction on commercial work until four years ago. That's when he got excited about concrete housing and started Safewalls of North Florida, Jacksonville, Fla. Until recently the company focused on large custom home work but decided that there was opportunity in the affordable housing market. He built several in the Pensacola area and is set now to build in Jacksonville.
Safewalls' homes are all concrete, also constructed with handset aluminum forms, approximately 2000 square feet, and sell for under $150,000. They include 6-inch-thick exterior walls with inside insulation, 9-foot-high ceilings, high-quality impact-resistant windows, upgraded roofing systems to resist 146-mph winds, appliances, and wood or stucco exterior siding. (The wood siding is wood fiber cement siding secured by nails shot directly into the concrete wall). Krantz says that he orders low-shrinkage 4500-psi concrete with 0.45 water-cement ratios and adds 20% fly ash to his concrete mix design. In addition, his homes have Energy Star ratings.
Krantz emphasizes being efficient on the job-site. His company uses forklifts to move everything around on construction sites, moving away from the use of cranes and knuckle-boom trucks to handle forms. By using handset forms instead of gang-forming systems, designs can remain flexible. They are also more efficient when you are building one house at a time.
“When I decided to build concrete homes, I knew I would have to market directly to the end user,” says Krantz. “People don't have much interest in concrete until they walk through a home and see and feel the benefits. Then they want it.”
Safewalls has patented a way to install a complete concrete room(s) including walls and ceiling in any existing wood home. In the event of a storm, such as a hurricane or tornado, families can take shelter in the concrete room and remain for hours if necessary. Krantz says there are millions of existing wood homes out there with absolutely no protection.
Building With Block
In Athens, Ga., Patrick Halloran, owner of Halloran Masonry, would like to be involved in affordable housing construction. He is convinced there is demand for this kind of housing construction in his area and that reasonable profits are possible. His company's current focus is custom home and commercial construction. They perform as general contractors when jobs require it. He thinks that incorporating subtrade work into his company's offerings makes it possible to provide affordable concrete block house construction at less than market prices. They proved the concept to themselves with the recent construction of an 1800-square-foot home. The affordable market in the Athens area is dead right now, as the result of subprime mortgage issues plaguing the country. When the housing industry comes back he plans to be involved.
The benefits of living in a concrete house include safety from disastrous weather events, fire safety, increased energy efficiency, low maintenance costs, protection from mold and fungus growth, and healthier living when companion building materials have low VOC ratings. Their initial cost may turn out to be a little higher than standard wood-frame construction. But when this happens, the additional monthly mortgage payment amount is more than covered by monthly savings for reduced energy costs, homeowner insurance, lower maintenance costs, and catastrophic events that end in complete structure replacement. Homeowners may even find themselves with more money in their bank accounts. And that doesn't factor in a higher quality of living and the impact that this housing has on the world community.