Skip to Main Content

Block Foundation Wall

A block wall uses masonry blocks that are stacked on top of each other and cemented into place using mortar.

When building a home, contractors first start with the foundation. Foundation walls can be made of poured concrete or concrete blocks. Whether you are just building your new home, or you live in a house with block foundation walls, here is everything you need to know about block foundation walls. 

What Are Block Foundation Walls?  

Block foundation walls refer to walls that are made from hollow concrete blocks. During construction, builders lay the blocks on top of the foundation footing and join them with mortar. Each row of blocks forms a course until the wall rises to the desired floor height. Rebar is then used to strengthen the walls.  

The width and thickness of the foundation wall footings depend on the block size in use. When erecting the walls, the builders must ensure the footing is as thick as the blocks are wide. And the footing has to be three times as wide as the concrete blocks. 

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 Groundworks. 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. 

Publish Date:

Last Modified Date: