How do I remove paint from a rendered wall?

Sean666

Hi everyone, first time user, long time visitor to Bunnings. 🙂

I have an issue with paint removal from a former external wall. We've added an ensuite to the house, now one wall that was external is now the entrance to the new addition. Prior to waterproofing I need to remove a fair amount of exterior paint. I've tried a heat gun and scraper, it took about an hour to do 0.5m2. Then I tried one of the grinding attachments on my angle grinder, but it's leaving gouge marks in the render and getting clogged. It'll be tiled over so that's not an issue, however it's quite time consuming also. I've considered using paint stripper from Bunnings, however I've been advised it might affect the adhesion of the waterproofing. May I please get some advice on the most time and cost effective way of removing this paint? There's only about 3 layers of paint but they've been there for 15+ years. Am I able to use paint stripper and ensure it's cleaned thoroughly prior to the waterproofing going on?

Many thanks in advance for any advice.

JacobZ

Hi @Sean666,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

Firstly, do you have some photos of the wall that you can share? Seeing what you're working with will help our members visualise the issue and offer their best advice.

Using a paint stripper is likely the best option, however, it can affect the adhesion of your waterproofing if residue is left after use. Luckily, addressing residue is fairly easy, and with a stripper like DIGGERS Paint Stripper, the user guide recommends that it can be done with water or methylated spirits.

If there is residual paint that can't be scraped off after an application of paint stripper, then a wire brush attachment such as this Wheel Wire Brush can be used, although it will likely remove some of the render with the paint. If used cautiously and sparingly, this shouldn't be an issue, as it will be covered anyway.

Please remember to keep safety at the forefront of your mind, as paint strippers can have some pretty strong fumes. Make sure you keep the windows and doors open and wear a mask while using it. 

If you use a wire brush, wear eye protection, gloves and long protective clothing to protect yourself from any airborne materials.

Let me know what you think, and if you have further questions, please don't hesitate to ask.

Jacob