Wall Cracks and Brickwork: DIY Repairs vs Professional Fixes in UK Homes

Noticed cracks in your plaster or loose bricks in your garden wall? Minor damage to walls and brickwork is a common issue for many homeowners in the UK, and in many cases, small fixes can be carried out with a bit of DIY skill and the right materials. However, when it comes to larger structural problems or long-term deterioration, attempting wall or brick repairs without proper knowledge can lead to further damage or mask deeper issues entirely. Whether you're patching small plaster cracks or considering repointing brickwork, it’s essential to know when DIY is appropriate and when it’s time to call in a professional.

In this guide, we’ll walk you through typical problems involving internal and external wall cracks, plaster damage, and brickwork deterioration. You’ll learn which tasks you can safely tackle yourself, and where hiring a qualified builder or plasterer in the UK is the smartest, safest, and most cost-effective option.

Understanding Wall Cracks: What Do They Really Mean?

Cracks in walls can be purely cosmetic, but they can also signal more serious underlying problems. In older UK homes, especially Victorian or Edwardian terraces, it's common to see hairline cracks in plaster caused by normal settling or temperature fluctuations. These cracks are usually harmless and often appear around window frames, doorways, or ceilings. They’re often no wider than 1mm and don’t affect the integrity of the wall.

However, deeper or wider cracks, particularly those that extend diagonally across walls or appear around the corners of windows, may indicate subsidence or movement in the building's foundation. In cavity walls, structural movement can sometimes cause the wall ties to fail, leading to visible cracking along mortar lines. Likewise, vertical cracks in brickwork, stair-step cracks in pointing, or bulging walls can suggest that the brickwork itself is shifting or deteriorating. These are clear signs that the issue goes beyond surface-level plaster repair.

If you’re unsure about the cause or severity of a crack, the safest first step is to monitor it over time. Take measurements and photographs, and track any changes. If the crack appears to grow, it’s a sign you may need to consult a structural engineer or a reputable builder.

DIY Wall Repair: When It’s Safe to Handle Yourself

For small, non-structural plaster cracks, such as those caused by seasonal expansion and contraction, DIY wall repair is a perfectly reasonable option. There are a few tips that can help you prepare for painting or other renovations. To fix small imperfections, begin by cleaning out the crack using a utility knife or scraper to remove any loose or crumbling material. Use a fine filler or jointing compound to fill the crack, then sand it smooth once dry. Finish by priming and repainting the area. There are many off-the-shelf products available at UK hardware stores specifically for this type of plaster repair.

For drywall or plasterboard damage, small dents or screw holes can also be easily filled with lightweight filler and covered with paint. Deeper gouges may require a patching compound and mesh tape for reinforcement. These types of cosmetic fixes fall well within the scope of DIY enthusiasts with basic tools and a bit of patience.

When it comes to brickwork DIY, some light masonry repair can also be done safely. If you notice a few cracked or weathered bricks in a garden wall or an outbuilding, replacing individual bricks is manageable with the right preparation. Chisel out the old mortar, remove the damaged brick, and set a new one in place using fresh mortar. Repointing the process of replacing old mortar between bricks is another task that skilled DIYers can attempt, especially in small sections. To do it properly, you'll need a mortar mix that matches the original, a pointing trowel, and a good understanding of the process.

That said, even with repointing brick DIY, attention to detail is crucial. Using the wrong mortar mix or failing to finish joints properly can lead to water ingress, frost damage, or further deterioration of the wall. For historic or listed buildings, any work on original masonry should be left to professionals experienced in traditional lime mortar techniques.

Please note, not every homeowner has the time, tools, or confidence to carry out wall repairs or light masonry work themselves. If you'd rather leave it to trusted hands, Adam Painters and Decorators offers verified professionals for painting, plastering, minor wall repairs, and full interior renovations across the UK. With next-day availability and an online price estimate in under two minutes, getting your wall issues sorted has never been easier. Whether it’s fixing cracked plaster or giving your home a fresh coat of paint, our team ensures a clean, reliable, and hassle-free service. Contact us today to get a Quote.

When to Hire a Professional: Spotting Structural Issues

While cosmetic cracks and basic patching are within reach of the average homeowner, more serious problems should not be ignored or patched over with filler. Cracks wider than 5mm, repeated cracking in the same spot, or any signs of movement in the brickwork indicate a possible structural issue. These may be caused by ground movement, foundation settling, wall tie failure, or even moisture ingress weakening the internal structure of a cavity wall.

If you're seeing signs like separating brickwork, sagging lintels, bulging plaster, or consistent cracking around extensions or bay windows, it’s time to hire a professional. An experienced builder or structural engineer will assess the source of the problem, not just the visible symptoms. In some cases, underpinning, wall stitching, or reinforcement may be necessary, particularly in homes affected by subsidence or with outdated foundations.

Interior walls that show consistent dampness, bubbling paint, or crumbling plaster may also signal more than simple cosmetic wear. Rising damp or water penetration through cracked render or pointing can result in long-term internal damage. DIY patching won’t fix the root cause; delaying professional repair can mean higher costs later.

When hiring a builder in the UK for masonry repair or wall restoration, always check for membership in recognised trade bodies like the Federation of Master Builders (FMB) and ask for recent project references. A skilled tradesperson will provide a clear quote, explain the root cause of your wall cracks or structural concern, and perform lasting repairs, not just cosmetic cover-ups.

Materials and Tools: Getting the Basics Right

For DIYers undertaking wall repair or brickwork DIY, the choice of tools and materials can make a significant difference in the outcome. For plaster repair, a good-quality filler, a flexible filling knife, sandpaper, and primer are essential. Avoid using overly rigid fillers on surfaces that are prone to minor movement, such as ceilings in older homes. For external walls, masonry filler and breathable exterior paint may be more suitable.

When tackling minor repointing work, use a mortar mix suitable for your wall type. For newer homes, cement-based mortar is common, but for older brick buildings, especially those built before 1920 lime mortar is preferred due to its breathability and flexibility. Using the wrong mortar can trap moisture, leading to spalling bricks or frost damage.

It's also important to match mortar colour and texture to maintain the aesthetic integrity of your property, especially if you’re working on a visible or historic façade.

Cost Considerations: DIY Savings vs Long-Term Value

DIY repairs can save a significant amount of labour, especially for minor jobs like internal plaster patching or small-scale repointing. For example, a homeowner may spend £30–£60 on filler, tools, and paint for a small plaster repair that would cost £150–£300 if done by a tradesperson.

However, professional repairs may save money in the long run by preventing further deterioration, water ingress, or safety hazards for anything involving structural movement, subsidence, or extensive repointing. Improperly handled brickwork can compromise wall stability, especially when mortar joints begin to fail at scale.

Choosing a builder with experience in masonry repair or structural crack repairs may cost more upfront, but it often results in better long-term value and peace of mind, particularly when warranty-backed workmanship is offered.

Final Thoughts: 

Whether you’re dealing with fine plaster cracks or loose bricks in your garden wall, the key to successful wall repair in UK homes is understanding the scope and cause of the damage. DIY wall repair is perfectly reasonable for surface cracks, isolated brick replacements, and light repointing. But as soon as cracks grow wider, repeat in the same location, or are accompanied by signs of movement, moisture, or instability, it's time to call a professional.

In short, know your limits. DIY is a great tool for light maintenance, but structural integrity is best left in the hands of experienced builders. With the right approach, you’ll not only protect your property’s appearance, but its value and safety too.