How to Fix 5 Common DIY Wall Mounting Fails

TV fallen off a plasterboard wall, leaving a hole in the wall.

So, you tried to mount something on your wall, and it didn’t go as planned? Don’t worry, we’ve all been there! Whether it’s a giant hole, a lopsided shelf, or (worst case) a leaking pipe, these DIY fails can be fixed. Here’s how to undo the damage and get it right next time.

In brief: Most DIY wall mounting problems come down to drilling in the wrong place, using the wrong fixing for the wall type, or misjudging the weight of what is being hung. Small holes can be filled and repainted. Larger holes need a repair patch or a section of fresh plasterboard. If you hit a water pipe, turn the stopcock off immediately. A crooked shelf just needs the screws loosening and the bracket resetting with a spirit level. And if a fixing has pulled out entirely, the answer is almost always to use a bigger fixing designed properly for that wall material rather than trying to reuse the same hole.

1. Installed Something in the Wrong Place? No Big Deal!

Oops – you drilled, installed, and now you realize it’s not where you wanted it. Not to worry, here’s what you can do:

  • If it’s just a small hole: Fill it with some ready-mixed wall filler, let it dry, then sand it smooth before painting over it. No one will ever know.
  • If you need to move the hole slightly: Instead of making loads of new holes, try using a larger fixing like a larger wall plug with a bigger screw.
  • If it’s a mess of holes: Consider using a plasterboard wall repair patch (essentially self-adhesive mesh) before filling and painting.
  • Remember: If you’re mounting a TV, check it’s at a comfortable height to watch without neck pain before you drill! You can do this by using a cardboard cutout or masking tape to visualise the placement before drilling. Ideally the centre of your TV screen should be at eye level when seated. A good rule of thumb is positioning the bottom of the TV around 42 inches from the floor. And remember to always mark drill points with a pencil and double-check measurements before drilling!

 

 

2. How to Fix a Hole in the Wall

Maybe the plasterboard crumbled, or your wall fixing ripped out? Either way, now there’s a gaping hole. Here’s how to repair it:

  • For small holes (under 2cm wide): Use a pre-mixed wall filler, apply with a filling knife, smooth it out, let it dry, sand, and paint.
  • For medium holes (2–4cm wide): Fill in layers. Apply filler, let each layer dry before adding more to prevent sagging.
  • For large holes (bigger than a golf ball):  Use a plasterboard wall repair patch or cut a small piece of plasterboard to fit, secure it in place, then fill around it with plaster or filler. For large holes in masonry, use a mix of sand and cement, or a specialist masonry repair filler. Whichever you use, apply it in layers and let each layer dry before adding more. Once it’s fully set, sand and paint as needed.

It’s also a good idea to use a primer before painting over any repairs to ensure an even finish.  

 

 

3. What to Do if You Puncture a Water Pipe

This is every DIYer’s nightmare, but don’t panic!

  • First off – turn off the water supply immediately. The stopcock is usually under the sink or near where the water pipe enters your home.
  • If it’s a small leak, you can temporarily seal it with plumber’s epoxy or pipe repair tape while you arrange for a permanent fix.
  • If water is gushing out, call a plumber right away!

How to avoid this next time: Use a stud finder with a pipe-detecting feature or check your home’s pipe layout before drilling. In UK homes, water pipes are usually found in these places:

  • Vertically above and below sinks, taps, toilets, and radiators.
  • Behind bathroom and kitchen walls, often running horizontally between plumbing fixtures.
  • Inside partition walls, often close to floor levels, especially in modern homes.
  • At floor level, where they run between rooms.

Avoid drilling in these areas unless you’re certain there are no pipes behind the wall.  

 

 

4. How to Straighten a Crooked Shelf or TV

Stepped back and realised your shelf or TV is looking wonky? Here’s how to straighten things out:

  • If it’s just slightly off: All you need to do is loosen the screws, adjust the bracket, and re-tighten.
  • If new holes are needed: Fill the old ones with filler, let it dry, sand, and repaint before drilling new ones.
  • For a foolproof straight mount: Use a spirit level when marking out drill points. A laser level works even better!

Stick a bit of masking tape on the wall and mark your drill points on that. After all, it’s easier to correct mistakes before you actually drill.  

 

5. Fixing Wall Fixings That Have Ripped Out

Did your fixing pull out of the wall, leaving a mess? This could happen if you used the wrong type of fixing or drilled a hole that’s too large. For example, a wall fixing or plug that doesn’t spread out or knot isn’t going to hold in plasterboard! Here’s how to secure your fixings properly:

  • For minor damage: If the hole is neat and small, you can just use a bigger fixing/ wall plug and screw. For plasterboard you want fixings that spread behind the wall to hold securely. If it’s a masonry wall, you can also try filling the hole with adhesive to hold the plug in tighter. Sorted!
  • For bigger holes: Fill the hole with a wall repair compound, let it set, and then drill again with the right fixing for your wall type.
  • For heavy items: Use heavy-duty fixings or toggle fixings designed for plasterboard or masonry walls.
  • Masonry walls (brick, concrete): Use wall plugs and masonry drill bits.
  • Plasterboard walls: Use hollow wall anchors or toggle bolts to prevent fixings from pulling out.

It’s important to know your wall type: Plasterboard, brick, concrete? The right fixing makes all the difference. We’ve got more advice on this in another blog post.

DIY fails happen to the best of us, but now you know how to fix them! The key is preparation – check for pipes and wires, use the right fixings, and measure twice before drilling.

We’re here to help you choose the right fixings. If you have any questions, just reach out to us on email or through our social media channels!

Frequently Asked Questions

For small holes under around 2cm wide, ready-mixed wall filler applied with a filling knife, left to dry, sanded smooth, and painted over is all that is needed. For medium holes between 2cm and 4cm, apply the filler in layers, letting each one dry fully before adding the next to prevent sagging. For larger holes, use a self-adhesive plasterboard repair patch as a backing before filling, or cut a small piece of plasterboard to fit the hole, secure it in place, and fill and sand around the edges. Always apply a primer before repainting to get an even finish over the repair.

Turn off the water supply at the stopcock immediately, which is usually found under the kitchen sink or near where the water main enters the property. For a small leak, plumber's epoxy or pipe repair tape can provide a temporary seal while you arrange a permanent fix. If water is flowing freely, call a plumber straight away rather than attempting a repair yourself. To avoid this happening in future, check your home's pipe layout before drilling, use a stud finder with pipe detection, and avoid drilling directly above or below sinks, taps, toilets, and radiators where pipes are most likely to run.

If the bracket is only slightly off, loosen the screws, adjust the bracket to the correct position using a spirit level, and retighten. If new holes are needed, fill the old ones with filler, let them dry fully, sand them back, and repaint before redrilling. For the most reliable result when marking out new drill points, apply a strip of masking tape to the wall first and mark your positions on the tape, as it is easier to remove and adjust than a pencil line directly on painted plasterboard. A laser level gives the most accurate guide for longer brackets with multiple fixing points.

The most important step is to identify why it failed before refixing. If the hole is still neat and small, a larger fixing designed for the wall type will usually work in the same location. For plasterboard, use a fixing that spreads the load behind the board rather than gripping only the surface. For masonry, fill the hole with adhesive to help the new plug grip, or move to a fresh location if the masonry around the original hole has crumbled. For heavy items, consider whether you are using enough fixings and whether they are appropriately rated for the weight involved.

Use a multi-function detector before drilling, as most detect both electrical cables and water pipes behind the wall surface. As a general guide, cables in UK homes typically run vertically down from switches and sockets and horizontally from them, so avoid drilling in those directions from any electrical outlet. Water pipes usually run vertically above and below plumbing fixtures and horizontally between them. If you are unsure, drilling a small pilot hole with a fine bit in an out-of-the-way spot before committing to the full hole gives you a chance to check what is directly behind the wall.

For a small hole in the wrong location, fill it with ready-mixed filler, sand smooth once dry, and repaint. If the item needs to move only slightly, see whether a larger fixing with a wider head will allow the bracket to shift position without needing a new hole. For a significant change of position, fill all the old holes properly before drilling new ones, and use masking tape on the wall to mark out and double-check the new position before you commit to drilling. For TVs in particular, it is worth using a cardboard template the same size as the screen to check the viewing height from your usual seating position before making any holes.

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