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Hi there,
In my hard plaster house, I have noticed cracks in the walls and uneven areas.
The cracks pictured haven’t broken opened the paint but are quite obvious. I have also included pictures where the plaster appears quite uneven and ugly. This house is very old (100+) and has barely had any maintainence.
What can I do to repair my walls that will make it smooth and crack free?
Thanks!
Hello @CourteneyWilko
Thanks for sharing your questions about your plaster wall.
It's great that you've received excellent advice from @Jewelleryrescue. I have to agree with Jewelleryrescue, those walls look pretty good despite being 100 years old. Which leads me to think that at some point the walls could have been replastered. As to what method was used is difficult to tell unless you start scratching and sanding the surface. But before you do that, I suggest getting your walls tested for asbestos just to be on the safe side.
If the results are positive, I suggest engaging the services of an asbestos removal specialist. If the results are negative, you can then proceed with your repairs. I propose engaging the services of a licensed builder who is familiar with traditional methods of repair and plastering. This is also an excellent opportunity to upgrade your walls using modern materials if it is applicable.
Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.
If you have any other questions we can help with, please let us know.
Eric
Good Evening @CourteneyWilko
I have to agree, thos walls are in good condition for their age 
The fine cracks and the uneven plaster remind me of walls I have where the previous owners/kids/teenagers someone has ended up against the wall and cracked it and then tried to repair badly over it.
With the house being so old I would sugest to have it tested as @EricL has mentioned just in case tho suspect it will be horse hair plaster as @Jewelleryrescue has also mentioned or more recent plaster,
If it comes back fine then I would be cautious (due to its age) I would create a fine small V cut that follwos the cracks (the point of the V being thecrack line itself.) I would use Selleys 180g Spakfilla Rapid Gap Filler - 180g and UNi-PRO Cork Sanding Block
IRWIN 1/3 92 x 230mm 120 Grit Un-Punched Sheets - 5 Pack or Paint Partner Assorted Sanding Sheets - 15 Pack will give you a range of grades. Start with the low number then medium and finally fine. You could skip the course stuff if you want (I cut the sandpaper squares into three strips the width of the sanding block with a pair of scissors)
The high points on the wall I would use the course stuff to smooth nback, when you can pass your hand over without feeling it (close your eyes) then use the medium or fine to finish it off.
With the dips/gouges plus the V channel you have created then you use a UNi-PRO 75mm Real Good Paint Scraper and take maybe 10mm over the blade and drag it over the V cut and also dips, use enough force to push the plaster into the hole and also scrape excess off. The holes dont appear to be deep so it should be easy enough. Let dry, Id let dry twice as long as container says Just to be safe. Then using a medium sandpaper sand as before, feel no ripples or almost no ripple switch to a fine grade of sandpaper. You will end up with a resonable amount of plaster dust so make sure you put down plastic sheeting. Try not to use your good vacumm cleaner as the plaster dust will kill it. Broom and dust pan I find is best.
Once you are happy then its time to paint I would give it overnight to dry befor e painting btw. Ive seen deep gouges take a bit to dry depending on the season and where you are located.
Dave
Thank you all for the amazing advice!
We also have deeper cracks in the walls. On another forum I read that the deeper cracks are best filled by opening up a little more in order for the render to bond.
as pictured, I opened some of the deeper cracks (which exposed the cement underneath - this is a double brick house). Now I am concerned this was the wrong this to do…
There are also some deeper cracks around door frames and skirting. I am wondering if I should remove the skirting, cornices and door frames when repairing the walls? I am very confused on the order in which to fix these walls!
Morning @CourteneyWilko
Those cracks are a little different. You mention a renderd wall so that leads me to a question. Is the surface of the cracks plaster or a cement render?
If its a cement render then it changes the product you would use but will let one of the guys suggest what type as I have not done a lot of render repairs. Just had a squiz over the types of interior render and it may be worth having a look at the depths and widths that a product will cover. It looks doable
The process I think will be the same. If its plaster then depending on how deep/wide the cracks are you may need some mesh over the crack to help bond/secure the section.
As to the last question, if you are intending to remove the skirting and/or door frames then I would repair them at that point. I wouldnt remove them as they are covering the cracks as is and you will be creating a lot of work that may never be needed.
Dave
HI @CourteneyWilko,
Opening the cracks up was the way to go. If these are cracks through the brickwork then you might need to have someone that specialises in house/wall stabilisation check them out. You might find your foundations need to be stabilised to prevent further cracking.
Now that you've opened the cracks (and determined that there are no structural issues with the wall or house), you can pack mortar into them. You'll then, once dry, render over the crack right up until about 5mm from the surface of the wall. The rest of the depth can be filled with Hardwall Plaster.
I'm in two minds about removing the door and skirting trim to fix the cracks behind them. I don't really see any reason to do this, and you certainly don't want to damage that skirting in the process, as it would be costly and hard to replace.
Please let me know if you have any questions.
Mitchell
