Have you ever wondered what kind of foundation types there are available for modern houses? I have and this list is a presentation of that. Before you commit to building foundations and footings, look a bit further for what concrete has to offer.
There are many types of foundations for houses. It’s reasonable that they all have their pros and cons as well. I’ve gathered a few concrete foundation types for comparison down below. One may not be better than another, but for those considering a building or buying it might hold some value.
Concrete block foundation
Concrete block foundation is the first popular type of foundation in the US. Concrete blocks are made out of concrete like poured concrete, only the gravel is smaller. Unlike poured concrete, concrete blocks are hollow. Blocks are stacked like bricks during construction.
When blocks are piled during construction, you can see from top to bottom of hollow parts. Later those will be filled and the wall is solid. Concrete blocks will also be reinforced with steel to provide a stronger structure.
A concrete block foundation has better carry capacity than poured concrete. If the building is heavy, it’s a good option. Seams are the weak point and if not done well or if there form cracks, it can leak water. Poured concrete can crack too if not done well or not maintained well.
Poured concrete foundation
A poured concrete foundation is another popular foundation type in the US. It’s as good as a concrete block foundation if done well. Personally, I think most of the things can last a long time and it’s a matter of preference which type of foundation is chosen.
It’s reinforced with steel to make it durable against surrounding forces like ground. Before the concrete foundation is poured, the footing has to be done with concrete. Then the wall forms are built upon it and poured. After forms are taken off and concrete has cured, it’s waterproofed so the soil won’t get concrete wet.
Concrete pouring, if done well, is a faster solution than blocks. Forms are relatively fast to set and pouring is also done fast. A vibrating tool has to be used on concrete so there will be no air pockets on the final product and it’s a solid pour. The cost of poured concrete foundation walls is also relatively low so that helps as well.
Concrete slab foundation
A concrete slab foundation is another popular way to set up a foundation for a house. Slab foundation cost is also one of its greatest selling points. It’s one of the cheapest options as it’s literally slab made of concrete.
If you want to check how to build a concrete foundation, I have a few examples on this site.
A slab foundation is poured as well, so it needs forms around it from wood during curing. The slab is thicker from the outside and thinner from the center. A slab foundation is also poured all at one go and is reinforced with steel or in some other way.
The greatest advantage of slab foundation is probably its slow cost, making it available for many. It’s also a fast way to set a foundation.
It can lower some energy bills like all concrete foundations, but the main fault is probably the possibility of cracking. Slab foundations don’t handle a freezing environment very well, there is a danger of cracking because of that.
I’d not advise on building a slab on grade foundation in cold climates, but wait for the summer if you don’t want to pay for weeks of heating.
Concrete pier foundation
A concrete pier foundation is like its name suggests, a vertical concrete pillar foundation. It can be used when you want your structure off the ground. The house frame, for example, is built upon multiple piers.
There are plastic forms for pouring piers for the foundation. These forms have the footing part on them as well so all can be done in a single pour. Traditional wooden forms can also be used and reinforcing should be done as well.
I see this kind of foundation as good where the ground is wet. It’s also good to take winter temperatures into consideration as frost heaves can potentially move the pillars if not done well. There are footing tubes actually that can at least partially resist this.
A basement foundation is a foundation that deeper underground and can be as tall as living spaces. That also makes it more expensive when you compare it to other foundations. It can be converted to some kind of living space if done well, which can make it a reasonable investment.
Extra living space would be its best selling point. Basement foundation can also be done on a slope so the sunlight can get in. It’s also good for a small plot of land where you can’t build wide but can go tall.
The downside of the basement foundation and its use as living space is moisture. Slope building could help with that with proper footing drain and proper waterproofing from inside and outside.
Precast Concrete Panel foundation
Precast concrete panels are like building blocks that come ready to build from the factory. Weather doesn’t play such a big role with these as they can be put up in almost any weather. Also because they are factory made, the panels are as strong as concrete comes.
Unlike most foundations, precast concrete panels don’t need footing. Building starts from gravel and panels for a house can even be set up in one day. Panels can also be insulated, so that would mean a house that keeps warmth during construction
The cost of concrete panels are on the higher side, but they do come insulated and with studs. That might help save money on the labor side. Fast setup also means lesser downtime on construction with less waiting.
Repairing concrete foundation helps you prolongs its age
To get the most for your money, it’s good to know how to repair cracks in concrete foundation walls. It is actually an easy and a basic tool like a hammer drill with a chisel bit is enough to get started. Or hammer and chisel depending on the crack type. Also, note the if it’s seriously split it’s best to call an expert over to estimate it.
Fixing foundation cracks from the outside isn’t too challenging. If it’s a small crack, use a hammer drill to get loose concrete off. Or hammer and chisel. Next mix some mortar that is meant for foundation fixing. If there is ½ inch or bigger crack, it would be best to call someone specialized to see it just to avoid bigger problems.
Sometimes the cracks outside might be caused by reinforcing steel that’s too close to the surface. If the steel is already showing and concrete has cracked off even hammer and chisel will do for the job. It’s important to get the space around the steel poking out clear of easily coming off the concrete. Something like finger width is enough most of the time.
If the steel is rusted, a hammer drill could be used to get to healthy steel that’s not rusted. It’s good to have at least 2-3 fingers width of healthy steel before patching.
Next, the steel and surrounding should be air pressured clean or sprayed clean with water if outside. Lastly, when the concrete is dry or a little moist, the spot can be covered with corrosion-resistant mortar and the surface leveled so it will look like the rest of the foundation.
There are also other kinds of cracks and also on the inside if it’s something like a basement foundation. Hairline cracks are usually nothing to get worried about. Those happen as concrete cures and shrinks a bit. The same can be seen on mortars as well.
If the concrete crack is bigger than the hairline it might still not be a problem, it might still be caused by curing. Still, it’s good to repair so that insects and moisture can’t get in.
Sealing it with something flexible is probably a bad idea as it hides the problem. There are some epoxy sealants that are a repair as well. The important part would be getting the repair deep into the crack as if we seal it only on the surface, moisture and water might eat the concrete from the other side and around the patch.
It’s good to be able to take care of your property, but it’s also good to leave potential risks to professionals. There is always a limit to what should be handled yourself. Foundation is what everything is built on, if it’s ruined it is just something that is pretty hard to fix.
As you can see, there are multiple options when building a foundation. Slab foundation might not be good where pier foundation would be best and the other way around.
It’s good to check out the pros and cons before planning further. Also, once you have your foundation placed it’s good to take good care of it so no big problems will take place.
If you’re interested in ways to support concrete foundations, here is an article about precast concrete piles. They help the foundations by supporting them deep underground from the solid ground if you’re building on soft land for example.