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100 Year Old Basement Walls Crumbling: How To Fix It Safely

A person’s basement can be one of the best rooms in the house – but if the walls are old and crumbling, you’ve got to get to work and sort them out before you end up in all kinds of trouble!

100 Year Old Basement Walls Crumbling

But what exactly are you meant to do? Luckily I’ve got all the solutions to your problems. This guide will cover why your basement walls could be crumbling, what you can do about it and some other handy tips going forward.

When your home is built, contractors generally build foundations that are designed to stand the test of time. However, time can be cruel to their quality and when enough time has passed, your walls can begin to crumble. 

Typically, this is due to oversaturated soil which places a lot of pressure onto the walls of your basement. This then pushes them inwards, and over time, erodes the concrete which causes cracks and disintegration. But there’s more to it than that.

Ready to find out a lot more? Then read on and discover the answers. 

How Do I Know If My Walls Are Crumbling?

Of course, the first thing you need to do if you suspect that your walls are crumbling is to inspect basement walls.

It’s recommended that you inspect your basement walls every five years to try to curtail any potential issues that could arise.

But what exactly should you be looking for during such an inspection? Below, I’ve explained the signs to pay attention to.

What To Look For During Basement Wall Inspection

When it comes to inspecting your basement walls, you should look at the following things:

  • Cracking, crumbling or bulging 
  • Leaning walls
  • Any indication that the walls are sliding inwards towards the bottom 
  • Any clear evidence of leaking 

You should also look out for any standing water, or water that won’t drain away. This is a red flag to the integrity of your foundations. Without any action, this standing water is a real threat to your basement. 

How To Repair Crumbling Basement Walls

How To Repair Crumbling Basement Walls 

There are a number of things you need to know when it comes to the repair of your crumbling basement walls. Here’s the most important information. 

Best Solution: Call A Professional 

I’d always suggest with a problem like this that you contact a professional if you have no prior experience in this field.

While fixing the problem yourself can be a great way to save money, it can also be problematic if you get it wrong. 

If you make an error when attempting to repair your basement walls, you could cause further damage which potentially can be costly. Therefore, to save money in the long run – I’d urge you to contact a professional right away.

However, if you’re set on doing it yourself or you have experience in this field, then you may consider the next solution. 

Repair The Walls Yourself 

Before you start work on your basement walls, you will need to ensure that you have:


  • 120 grit sandpaper 
  • Putty knife 
  • Dust mask
  • Trowel
  • Plastering contractors

Once you’ve got these, it’s time to get started! 


You need to begin by preparing the surface and make sure you brush any loose concrete off, because your repairs won’t last if you don’t. This is one of the reasons it’s essential to have a dust mask, so you don’t breathe in any dust.


Once you’ve prepared the surface, it’s now time to waterproof the basement wall. At this point, you need to apply a water-based epoxy basement waterproof coating onto the wall, which acts like a bonding agent.


Now that all the starter steps have been completed, it’s time to get into the real stuff. Combine your water based epoxy with sand and concrete mix so you can resurface the wall. 

Skim the mixture you have made over the surface of the affected wall – and do thin skimming when the mortar is loose. If the mortar gets thick, you’ll need to apply a chunking filling over any large cracks.

Once the correct applications have been made, you need to ensure you wait for approximately 24 to 48 hours to allow the composition to settle. After this time, you should then reinspect your basement walls. 

How To Prevent Basement Walls From Crumbling 

Of course, the best way to solve the problem in the future is by preventing it in the first place. While crumbling walls are somewhat inevitable in some respects, you can still reduce their likelihood. 

The first tip I can give you is to not allow the walls to dry out too quickly after you’ve resurfaced them. It’s a good idea to keep a spray bottle handy and give them a quick refresh every now and then.

The second tip I’ll provide you is that it’s wise to cover the resurfaced wall with polythene because it can help to trap moisture, which feeds into the previous point. 

Finally, try to avoid letting the walls be in direct sunlight for too long. If you have windows in your basement, consider covering them with curtains or something similar.

When exposed to direct sunlight for too long, the walls’ surface can easily and quickly dust.

Final Thoughts 

100 year old basement walls are prone to crumble, and if you’re unfortunate enough to have to deal with this problem, I’d first advise you to contact a professional right away unless you have some experience in this area. 

However, if you do have some experience – then I wish you good luck and I hope this guide has been helpful for you!

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