How to permanently repair hairline cracks in wall & ceiling plaster – DIY decorating guide

This how2everystep video shows you how to permanently repair a hairline crack in wall or ceiling plaster.
In 6 easy to follow steps…

Every Step Summary
Step 1: Tap to check the plaster is attached to brickwork
Step 2: Open up crack with Stanley knife
Step 3: Clean away any dust from crack
Step 4: Push filler into crack
Step 5: Fill again to level with surrounding plaster
Step 6: Paint the crack area

Tools / Materials Required
1: Fine filler
2: Flexible scraper
3: Stanley knife
4: Cloth
5: Paint (and roller)

[PaulJones-bwio]

Hi i have a plasterboard ceiling crack from a ensuite leak, can i do the same or will i need to use ghat white mesh tape ?
Also if you put tape on then put a mix on top wont the finish look bulky ?

[DonTruman]

I was trying to find the style of scraper you used to spread the patch. Finally found it: looks to be intended for auto body repair, "Body Filler and Putty Spreader." Looks like it's good for this kind of work. Better control of it, and the angle might be better for your hand when working on a wall, especially when it's up high.

[lowkeyconvert]

hello, I noticed you didn't appear to use any plaster jointing tape on the crack like some do. is this still okay?

[nelsoncaraballo]

Video came in handy. Your idea of making crack larger with utility knife or a tool makes perfect sense. Now you have more area for new player to grab on too for a better finish. Thank you. Nelson in Boston.

[raj]

what do you mean by when you say "check plaster is not detached"? Do you mean when it sounds hollow?

[Kaosinlondon]

Does it work this way without cracking again?. I usually make the crack much deeper and wider and then fill it, I have even gone as far as filling it with bonding and then putting filler on it.

[mcnegro]

Can you not just break the old plaster and then replaster it? Or just whack on plasterboard on the brick wall after applying bonding?

[theIII]

Great music ima sample it for a beat. And play it while I fix the crack in my ceiling!

[sumanchandrabhan]

Which chemical to use to treat hairline crack in roof

[scarbo]

There is a tool that’s specifically for opening cracks, so you don’t need to use a box cutter knife sideways. Some plaster is quite rigid, so I would imagine the sideways box cutter blade would be slow going. Also, I would recommend spot priming with a high quality primer before painting.

[jonlen]

I have a hairline crack that runs the full length of my bedroom wall, I have filled it about 4 times it always comes back. Brick & plaster.

[jonathanbirley]

If there is movement in the plasterboard then the crack will continue to reappear. I had this problem around staircase strings and found Soudall foam filler did a great job of stopping the movement then I filled over. A bit of diluted PVA in the crack once opened helps give the filler someone to grab onto.

[IknowGodIs]

Do you have a video in which you are plastering the ceiling after removing sagging repair work that someone else has done incorrectly? I understand that I’m going to need to scrape off everything that sagging and begin again, but I’d love to see that actually done.

Both of my bathroom ceilings had cracks and someone decided to tape and spackle over them. Now all of it is loose.

[Opia]

Great! Is it not necessary to sand before painting?
Thx

[BigRustyJoe]

Started the video wanting to fix a crack, finished the video wanting to smoke some crack and go to a rave

[colinevans]

This method don't always work on ceilings has the cracks can re appear, well mine did, great video but don't always work on ceilings. I used uni bond, fibre glass, brushed again with uni bond let dry then skimmed over with easy filler, still great after 12 years about now

[elsewho]

Step 1 should be.. diagnose what is causing the crack. Is it truss movement in a ceiling? Sometimes truss’s are not secured properly and movement causes cracks. They should be battened to prevent movement. Are the slabs nailed/ screwed at the centre of each joist/truss? If a slab is 8 x 4 the crack is typically on the 4 ft part if not secured correctly. If 4 x 2, on the 2 foot end. The slabs should also have being taped and jointed at each meeting. If not done cracks will appear. Fill the crack like this video, but if it reoccurs you probably have something else that needs fixing.

[susanr]

Thank you. Is the filler a Bondo type product, or spackle?

[MrCrabbing]

Thanks Colin I will give that a go this weekend

[chrisjarvis]

Hi, Can you tell me what filler you used on the crack please?