How to Fix Cracks in Walls Using Building Materials and What to Avoid

Finding a crack in one of your walls - any of them - isn’t how you want to start your day, but there’s no reason to worry. Most cracks can be fixed relatively easily, depending on how big it is and the wall in question, with the right building materials.

Indoor and outdoor walls can suffer from cracks for a number of reasons and there are plenty of ways to fix them before they get worse. Act quickly and you might not need a specialist to help you.

That said, there are also some things you should avoid doing. There are plenty of home remedies or ‘life hacks’ that might seem quirky at first, but don’t get sucked into them. We’ll give you some examples and you can see for yourself the lengths some people will go to.

You might be surprised at what some people have come up with.

What you should do about cracks in the wall

1. Investigate the crack

Cracks can appear anywhere, both inside and out of the property.

Inside, they’re more obvious on walls and ceilings - although smaller cracks might be concealed by wallpaper - but cracks in the floorboards can also appear. Given that these are under carpets and other types of flooring, they’ll be harder to spot. You can still watch for any changes in the floor as you watch, whether that’s uneven surfaces, slight rises or excessive creaks. All can indicate a larger problem.

Cracks in outside walls are rare, and require a lot of force or external pressure to create this amount of damage. This is also why different building materials are used at different stages of construction and for various parts of the property.

Once you’ve found the crack, you’ll want to look at how big and how deep it is. A small crack can be fixed in different ways to larger, deeper cracks. It also depends on where the crack is and whether the wall is weight bearing or not.

Once you have an idea about the extent of the damage, you can think about what to do about it, and what building materials you need to carry out the repair.

2. What building material has cracked?

Depending on how old your house is, and where the crack is, you need to find out what material has cracked.

Inside, the main parts that could crack are wooden beams, brick or plasterboard. Combine this knowledge with the size and depth of the crack and you’ll be able to get the right building materials to fix it.

External walls are most likely going to be brick, which can also present structural issues if the crack is too big. This might require more intensive work, but cracks on these walls are less likely to occur than those on the inside.

3. Fixing the crack

For small cracks, especially those on the inside, you can use filler seals directly in and around the damage. This is usually done with a pump or gun, as either a foam or putty that can fill and expand in the gap. Simply apply, smooth over, wait for it to dry or set, then apply a coat of pain until it’s not even noticeable. It is that simple.

With larger cracks, it might be too difficult to use a filler product - not to mention that it might have a structural impact. In that case, you might need to replace that part of the wall. This might seem tricky, but internal walls - especially in modern houses - often use plasterboard between rooms, and this is what might crack. There are plenty of places to get cheap plywood sheets or plasterboard, and once decorated it will be nearly impossible to spot the difference.

Once identified, you can remove the damaged piece or cut around the damage and measure out a new piece to fit in. Cheap plywood sheets or boards come in different sizes and thicknesses, from 3mm plasterboard and larger depending on what you need.

Take your time, make careful measurements but don’t be afraid to replace the damaged boards completely if that will be easier for you.

What not to do with cracks in the wall

We’ve come across some pretty crazy repair solutions over the years, and some are too good not to share.

That said, we don’t recommend trying them!

1. Don’t use pasta or noodles

Most of us have come across this way for testing if spaghetti is cooked; you throw it at the wall and see if it sticks. This might be a great cooking method, but would you believe that some people have the idea that, since it sticks to walls, enough pasta would be a great option for filling in cracks?

Believe us, it happens.

Not only will this do nothing to fix the damage, but before long you’re going to have mouldy food in your walls. It will smell and eventually degrade. Moisture will seep into the rest of the wall, too, making the damage even worse over time. That means more work and more building materials to fix properly.

2. Stuffing the crack with paper won’t work

We’re not really sure on the logic behind this one, but we think it’s more of a paper mache than scrunched up newspaper.

To avoid adding extra weight to a wall with a crack, filling it with paper seems like a good plan - until you realise it adds no structural value whatsoever. The water used to compress and mould it seeps into the wall to cause more damage and it will do nothing to help with temperature or sound regulation. You might save money short term, but cheap plywood sheets are going to be a better investment.

We’d avoid this one.

3. We don’t advise trying concrete

Especially for outdoor or brick walls, you might think this is a great solution and get on with it, but nope! The concrete will fill the wall but not meld with the bricks - you need a mortar solution for this to work, which is very different and requires broken bricks to be removed and replaced, too.

Not only that, concrete will add more weight to the wall, which could cause problems. The same is true for internal walls made from plasterboard. The concrete will weigh it down and damage it - and potentially damage your floor, too!

Get Building Materials and Start Fixing Cracks in Walls!

As you can see, there are plenty of ways that you shouldn’t try to fix cracks in a wall but some easy methods you should absolutely follow. We do recommend going to a hardware store where you can but you can also get your building materials online and have them delivered if this is easier for you.

One thing to watch out for, if ordering online, is extra costs. Some materials can be large or better ordered in bulk - especially if you have a DIY project coming up - so make sure the cost of the building materials being delivered doesn’t cost more than the materials themselves.

If you have any questions, contact our team and we’ll be happy to help how we can.