What Lies Beneath Maintaining Your Building's Foundation

What Lies Beneath

 They say a house is only as strong as its foundation. A bad roof, or shoddy  plumbing can set your building back a lot of money. But, a foundation in  disrepair can put the entire building's structure at risk. It can also cost  tens of thousands of dollars. Since it's literally underground, it's easy to  ignore, and difficult to notice, but the health of a building's foundation is  crucial. A little bit of education from the professionals can go a long way to  raising anyone's awareness on the importance of a good building's foundation.  

 Every region has its own architectural history, and New England is no different.  “We have old rubble foundations, granite block foundations, there's a little of  everything,” says John Luther, building commissioner for the Town of Carlisle in  Massachusetts. Often foundations can be one of the best ways to date a house or  building, and the New England area has some of the oldest housing stock in the  country, and therefore some of most diverse foundation structures.  

 Not a Rolling Stone

 The oldest foundations tend to be made of stone. Builders used to different  kinds of mortar as well—in some instances a mud-based one. New England's buildings can also feature  brick foundations, and even dry-laid foundations, in which stones were stacked on top of one  another with no mortar. Many such constructions did not last long in more precarious terrain, but some  parts of New England have allowed old constructions to stay strong. Even now,  you can see hand-made construction still intact. Before construction became  more machine-based in the twentieth century, every step of home construction  was also done by hand, giving builders limited options.  

 By the 1910s, poured concrete foundations became more common than stone. The  different types of construction can lead to different problems. “They're different animals, they're built in different times. It all depends on  the code stated at the time of construction,” says Luther. Since condos tend to be newer developments, they almost never  contain brick or stone foundations.  

 Since, modern structures almost exclusively use concrete-based foundations,  engineers and property managers have to look out for issues with that in mind.  Even though it's a stronger material, concrete foundations face the same enemy  as any other foundation: water.  

 Though some parts of the country can run into foundation issues because the soil  is too dry, the Northeast rarely runs into such a problem. Most  foundation-related issues have to do with rain and improper drainage. If a  building doesn't have a proper drainage system in place, the surrounding soil  will erode. “Usually all erosion really starts with water issues, but certainly some soils  erode more easily than others,” says Timothy Wentzell, P.E., a principal at Connecticut Property Engineering in  South Windsor. “The foundations start being exposed, and there's frost issues, and potentially  even more leakage issues,” he says.  

 Varies by Location

 Foundation problems almost always have to do with location. “Connecticut has a fair amount of sandy soils and clay soils. Both of those are  little more difficult to compact, especially in the presence of water,” says Wentzell. Before construction of a foundation, inspectors have to make  sure that the underlying soil has been properly compacted, so it can  effectively anchor the building. A common problem arises when “the materials on the floor may not have been compacted enough—like a garage floor that may develop cracks. When you go in and you tap on it  with a metal rod, and hear different sounds in the floor often that means part  of the ground wasn't compacted enough,” says Wentzell.  

 Drainage can be a dangerous issue for foundations in some areas of New England,  and for the average resident, the warning signs come very far down the road. “We saw a case where a building's basement floor had about a three-foot void on  the descent, and the concrete floor sagged, and we cut a hole in the floor and opened it up, and you could climb in there. There was an underground stream that had slowly over time washed out the entire  basement floor,” says Wentzell.  

 When too much moisture gets into the soil around the foundation, the concrete  walls and floor will move with it, which can compromise the safety of the  structure. “Part of the building drops,” says Wentzell.  

 In other areas water and soil settlement pose less of a problem. “Eighty percent of Massachusetts is pretty solid. There are some spots closer to  the coast or down in the shore that have some sediments that you don't want to  build on, but inland it's just rock,” says Luther. The Massachusetts area tends to have less issues with drainage and  settlement, so long as the proper inspections take place. “Once contractors do an excavation, we do an inspection to make sure it's on  suitable soil,” Luther.  

 Inspect, Inspect Some More

 Drainage inspections are also an important step. “If you're building correctly, you shouldn't have a problem,” says Luther. But, in parts of Massachusetts, rather than rain runoff, the water  table is the greater concern. “Sometimes you get groundwater that comes up, but you shouldn't have gone too far  underground. You just check the water tables. It's pretty simple out here,” says Luther.  

 Concrete, as a material, has some unique qualities. “Concrete gets stronger over a fairly long period over time. You probably see  more problems in a 20-year-old building than a 50-year-old building, because  the problems in a 50-year-old building have long since been resolved,” “Concrete takes a long time to cure. You may be able to walk on concrete two days  after it's poured, but its strength doesn't materialize for a fairly  significant period of time. The normal testing is done at seven days and 30  days, but realistically it probably continues to strengthen for the good part  of the first year,” says Wentzell  

 Under the right care, concrete is the most dependable material to go up against  nature. “Generally, concrete really shouldn't crack if it's done correctly,” says Wentzell. But, while concrete is the modern choice for any new  construction, it's not foolproof. “A lot of things can go wrong when you pour concrete,” he says. Foundation walls will cause problems if the concrete, when it was  poured was too dry, too wet, or at a bad temperature. “You can't pour concrete when it's too cold unless you take means to protect it.  If it freezes before it cures completely, it'll have a lot cracking and  crumbling, you know lots of different issues,” says Wentzell.  

 Follow the Rules

 Generally speaking, a lot of complications can be avoided if contractors and  developers simply follow the rules and regulations. When it's a smaller  project, corners don't get cut as often because they'd be more obvious, but  also because there's less capital and moving parts on the line. “The problems get worse with multifamily housing,” says Wentzell. “The oversight during construction is just a lot poorer. The first unit is often  built better than the last unit. Quality control and oversight can be  problematic in big projects,” he says.  

 Before you can build a house you need to start with a solid foundation.  Unfortunately, most New Englanders who move into a new condo or building are  stuck with whatever foundation that came with it. Still it can be helpful for  boards to know that foundations can be a factor in capital projects, and that  property managers should be well-versed on the warning signs of foundational  trouble.    

 Tom Lisi is an editorial assistant at New England Condominium and other  publications.  

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