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Block Foundation Wall

Block foundation walls that are built the right way and reinforced can be extremely strong and durable.

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One way to prepare for home construction is to know the type of foundation wall that your builder or foundation contractor might erect. Such knowledge will help you understand the nature of foundation walls and some of the issues associated with them. 

Here, we are going to explore the world of block foundation walls and what you can expect from them. In the end, you should have a good understanding of this type of wall and be able to decide whether it suits your construction needs. 

block wall

What Are Block Foundation Walls? 

Any foundation wall that’s built from hollow concrete block walls is known as a block foundation wall. This type usually goes 1.5-2” deep. To erect a wall, workers lay blocks on top of the footing to form a course that goes up. 

Block foundation walls are a common sight in the Greater Denver, CO, area. They’re typically made of a mixture of cement and sand. In some places, builders use stabilized earth blocks. Standard blocks are 8” x 8’’ x 18’’, with two flat sides and two vertical and hollow cores that are notched at their ends. There are also half-width blocks for sidewalls and corners. 

Constituent blocks are joined using mortar and the walls are strengthened with rebar. A properly designed and built block foundation wall has comprehensive strength that provides steady support for the vertical loads on your walls. 

How wide and thick your wall’s footing will be depends on the size of the concrete masonry block being used. It’s advisable that the footing be as thick as the block as wide. The footing should be at least three times the widths of the blocks. 

What Are Their Pros and Cons? 

Walls made from concrete blocks have some unique advantages over poured concrete walls. Builders don’t need to piece together wooden forms or secure them properly before mixing and pouring concrete. 

Another benefit of erecting this type of wall is that the blocks are light and easy to install. A small army of masons, led by a skilled foreman, can erect a block foundation wall within a couple of days. Your workers don’t have to set up formwork or wait for the concrete to cure before they can continue with work. 

Concrete blocks also result in strong and well-insulated walls. It’s also easy to rebar these walls to enhance their strength. You’ll also be glad to know that blocks are versatile. You can use them to construct a foundation in an area with seismic activity. 

On the flipside, block walls are vulnerable to water. Exposure to moisture or water over time does weaken and wear away the mortar between their joints. Water may start infiltrating your basement through exterior joints. Walls that are built without any reinforcement are susceptible to movement when the soil gets wet. 

Should You Reinforce Block Foundation Walls? 

These walls ought to be reinforced immediately when the last block is laid. Local codes determine how much reinforcement is needed. Reinforcing the walls entails pouring mortar or concrete right into their voids. Some builders use concrete with smaller gravel. Another rebar option is using 1 ½-inch steel rods. All these materials can help strengthen your block walls. 

Waterproofing Your Foundation 

Moisture is the #1 nemesis to any block foundation wall, as it has the potential to degrade the wall and shorten its lifespan. 

When waterproofing the exterior walls of your home, the builders will use a prime, a membrane, and sealant. They may also create drainage channels along the footer. Once the exterior drainage is set up, backfill soil is used to fill the space between the ground and your foundation wall, covering all the waterproofing. 

You also can curtail water damage by hiring a foundation contractor to waterproof your walls. The solutions they will deploy will stop moisture and water from the ground from seeping into your basement. These include interior drainage, a sump pump, and a vapor barrier for the walls.  

Are there cracks or gaps on the walls? These have to be sealed before waterproofing starts. Otherwise, they will widen and allow water to infiltrate your basement. Leaning or bowing walls also need to be reinforced and straightened so they won’t collapse when water starts pushing against them. 

If you would like to repair your foundation or seal cracks on your foundation wall, contact Complete Basement Systems for a free waterproofing inspection and quote in the Greater Denver, CO, area. We use long-lasting solutions that are backed by warranties.