We'd like to remind Forumites to please avoid political debate on the Forum. This is to keep it a safe and useful space for MoneySaving discussions. Threads that are - or become - political in nature may be removed in line with the Forum’s rules. Thank you for your understanding.

How to fill large hole

Ben1989
Ben1989 Posts: 470 Forumite
Fourth Anniversary 100 Posts Name Dropper
Hi all. Had a small hole appear in the plaster after scraping wallpaper off the wall. I knocked off all loose plaster until I got to solid stuff and ended up with quite a large hole.

I’ve been building up layers with ready mixed filler and I’m at a point now where the next layer will like come flush or protrude from the wall. 

I’m just wondering what the best method, products and filler is from this point to get a nice smooth finish. Or, what’s best for sanding? 

I’m hoping the picture of the semi-filled hole has made its way through. 

Thanks in advance!


Comments

  • fenwick458
    fenwick458 Posts: 1,522 Forumite
    Part of the Furniture 1,000 Posts Name Dropper
    I'd give that a light sand to knock off any high bits (or just knock off the high bits with a trowel, filler knife, scraper)
    then put another layer of filler on and scrape it as flat as you can(it will be a bit proud of the rest of the wall)
    then when it's dried sand down to a smooth finish
  • Ben, do you have an actual plastering trowel? This would span the hole completely, so would give you the correct level for the filler.
    First you'd use it like a scraper, held at 90o to the wall - pulling it across would show up any high spots, and even scrape them off. You need to do this first - get the highest spots down to wall surface level.
    What filler did you use for the job so far? Is it ready-mixed stuff, or was it a powder you mix with water and then it 'sets' chemically?
    If the former, then you first need to allow the stuff already there to dry out completely, or else it'll be soft and take even longer to dry.
    If the latter, then you should be good to go.
    The problem with adding additional layers of filler to old is that the old will suck the water out of the new, could make it crumbly, and could even compromise the adhesion. So, after the under stuff is completely dry, I usually then dampen it slightly - perhaps wipe a damp cloth over it, or give it a light spray with a hand sprayer.
    (If it's a powder filler, so set but still a bit damp, just fire away - it should be fine).
    Get/make up the new mix, and apply it using the trowel - or just slap it on and then use the trowel. If you hold the trowel at a high angle like a scraper, the surface will likely end up slightly below wall level when set/dry. That doesn't matter - you just apply a further skim. If you run the trowel over it at a low angle - 20-30o - then it'll tend to leave the skim layer fractionally above wall surface level. Doesn't matter which you do - just 'play' with it and watch what happens - go over it if you are not happy with the finish.
    If it starts to 'drag', then give the surface a light mist spray of water and that should help it to smooth out nicely.
    When 'happy', leave it, let it set/dry fully, and then sand it all flat and level using a large comfy sanding block and 120-180 grit.
    (Don't try and get the surface 'perfect' using the trowel 'cos it'll almost certainly be a waste of time - you are using 'filler' and not 'skim'.)
  • stuart45
    stuart45 Posts: 4,585 Forumite
    Sixth Anniversary 1,000 Posts Name Dropper
    When you sand it, run your fingers over it when finished. Anything you can feel will show up when painted, so keep on sanding.
  • If you use one of these -   https://www.screwfix.com/p/stanley-hand-sander-230-x-80mm/8332k    - you cannot really go wrong.

  • Ben1989
    Ben1989 Posts: 470 Forumite
    Fourth Anniversary 100 Posts Name Dropper
    edited 13 August 2021 at 7:18AM
    Thanks all. Yes it was filled with Screwfix's ready mixed filler.

    Jeepers no I do not own a trowel. I think you're right and I need to invest as i cant have my current knives/blades on either side and are just 'floating' when i put the filler on. I have a block sander thanks that has been really handy with smaller holes and jobs.

    I'll be getting a trowel from screwfix today. Is it worth using polyfilla? I find it easier to sand but could compromise robustness? Doesn't seem to be a material designed for large holes like this. Could be wrong.

    This is the stuff I am using https://www.screwfix.com/p/no-nonsense-interior-ready-mixed-filler-white-off-white-1kg/555gt

    I'm open to other suggestions if this is not sufficient
  • NSG666
    NSG666 Posts: 981 Forumite
    Part of the Furniture 500 Posts Name Dropper Combo Breaker
    edited 13 August 2021 at 7:31AM
    Use Polyfilla Easy Sand for the final finish. If the filler you use is too hard, when you try to sand it if the surrounding plaster is softer than the filler it's difficult to get everything flat even with a large sanding pad. No such issues with the Easy Sand - that's my experience anyway. Sand with 120 grit just lightly so it allows the sanding dust to drop clear.

    Depending on what you are going to do next you might want to mix the filler with a bit of paint to make a hard stop filler - google it.

    Looking at the existing filler you might want to invest in these for applying it Harris Continental Filling Knives 3 Piece Set | Knives & Scrapers | Screwfix.com
    Sorry I can't think of anything profound, clever or witty to write here.
  • stuart45
    stuart45 Posts: 4,585 Forumite
    Sixth Anniversary 1,000 Posts Name Dropper
    I've got a set of those knifes. Good value, but I keep them oiled as they tend to rust easily.
Meet your Ambassadors

🚀 Getting Started

Hi new member!

Our Getting Started Guide will help you get the most out of the Forum

Categories

  • All Categories
  • 348.2K Banking & Borrowing
  • 252.1K Reduce Debt & Boost Income
  • 452.4K Spending & Discounts
  • 240.8K Work, Benefits & Business
  • 617.1K Mortgages, Homes & Bills
  • 175.6K Life & Family
  • 254K Travel & Transport
  • 1.5M Hobbies & Leisure
  • 16K Discuss & Feedback
  • 15.1K Coronavirus Support Boards

Is this how you want to be seen?

We see you are using a default avatar. It takes only a few seconds to pick a picture.