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Cinderblock foundation wall

Block Foundation Wall

Foundation walls constructed from concrete blocks are prone to various water-related problems. Here’s what you should know about them.

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Chances are that your home has a basement or crawl space. Some 42 million homes across the U.S. have basements, making them strong favorites when it comes to below-grade units. And it’s no wonder since they’re pretty useful when it comes to expanding your living space or using them as storage. But what type of walls do these basements have? 

Some of the most popular types of designs use concrete blocks. Like others, these walls have their pros and cons, there’s no doubt about it. Here, we’ll delve into how builders make them and how you can improve their state to withstand numerous water-related problems such as mold and mildew. 

block foundation wall

What Are Block Foundation Walls? 

It’s only fair to first explain what these walls are before we head into other details. Namely, construction crews build block foundation walls by placing hollow concrete blocks onto one another and joining them together using mortar. 

These walls sit on top of footings that builders dig up and pour beforehand. Each row of blocks forms its course until the wall reaches the height that the basement requires.  

Block foundation walls are rather common, and rebar (reinforcing steel rods) is used to strengthen them. Unfortunately, like most construction elements, block walls are no strangers to various problems. From allowing water to leak into or flood the inside of your basement to letting pests through cracks between the joints, they’re not perfect. Still, you can make sure none of that happens with professional help. 

Block Foundation Walls Have a Long History 

It’s no secret that builders have been using blocks for construction for many years now. However, it wasn’t until the beginning of the 19th century that Americans would begin to use them for housing. Builders would construct the first block building in America, in Staten Island, New York. 

By the end of the century, Harmon S. Palmer would patent the first hollow concrete block. This design would pave the way for builders to start using blocks made from a mixture of gravel and sand. 

It wasn’t long before everyone fell in love with them. The thing is, these blocks are light and easy to store, unlike stones or bricks. Their main use today is for foundation walls that are beneath the ground level. Concrete blocks weigh around 40 pounds and measure 16″ x 8″ x 8″. 

Pros of Block Foundation Walls 

The thing that makes them a firm favorite among builders and homeowners is the fact that they can carry huge loads. Interestingly enough, their load-bearing capacity is even bigger than that of poured concrete walls. And if the construction crew builds such walls properly, they can prove to be sturdy foundations for the rest of the building above them. Using them as retention walls will keep the rest of the structure stable for the foreseeable future. 

On the other hand, it’s not just their strength that makes them so great. They’re pretty easy to construct which can help to lower the cost of labor. An experienced crew will assemble them with ease, way faster than most other types of walls. All they’ll need to build them are some shovels, a mortar mixer, trowels, and levels. In other words, block foundation walls are a perfect choice for anyone who’s on a tight budget, looking to save money for other construction elements. 

Cons of Block Foundation Walls 

Just like anything else out there, concrete block foundations have their negatives too. They’re prone to bowing and buckling at times. As such, you’ll need to repair them. But there’s another catch. Skillful masons don’t come around that often these days. 

Yet another major issue you can have with block walls is their inability to withstand water like some more modern constructions. Harsh weather will, over time, wear off the mortar from the wall, damaging it gravely. Of course, you can still waterproof them with professional help. 

Reinforcing Block Foundation Walls 

Most professionals will suggest that you reinforce your block walls. And if you opt to do so, they’ll pour concrete or use cement-based mortar to fill the voids between the blocks. In most scenarios, builders will use small gravel concrete because it can flow better while filling the gaps. We also recommend that they use half-inch steel rods between these voids from the bottom up. 

Common Issues with Block Foundation Walls 

The main enemy of your foundation is hydrostatic pressure. This is a form of water and soil pressure that can cause your basement walls to bow. And with time, it will wear out the mortar between the blocks and its joints, allowing water to seep through. The best way to deal with this problem is to waterproof your basement. 

Waterproofing Your Block Basement Walls 

To keep moisture out of your basement, you’ll need to waterproof it. When constructing your basement, the builders should apply a water-resistant membrane to cover the walls. This will help keep water out of and away from your walls, but it can wear away with time. 

The crew might suggest installing a drainage system to collect excess water and direct it away from your basement. Of course, once they put the system in place, the crew will backfill the trenches and compact the soil. Your yard will look nice and tidy just as it was beforehand.  

The best way to waterproof your basement walls is with an interior drainage system and a sump pump. These measures are placed in your basement to intercept any leaking water and pump it out of and away from your home before it has a chance to damage your basement. Your local basement waterproofing professionals can install these solutions for you, as well as fix any block walls that may be bowing with carbon fiber supports, wall braces, or wall anchors.  

So, if you’re looking to waterproof and fix your block foundation walls, you can count on professional help from our team at Tar Heel Basement Systems. After scheduling a free inspection and repair quote, our team will visit your home to complete a thorough evaluation and advise you of what repairs your basement will require. You can count on us to keep your home safe from water for years to come. 

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