Share
Hello Community!
Firstly some amazing DIY posts on here truly inspired to try, learn and do more!
I have been researching heavily on the pros and cons of bagging Vs painting with texture paint on a garage renovation.
Painting seems like a more achievable option but at higher cost. Leaning this way
At present
My main concern is getting advise on preparation as the besser blocks have moisture and white residue plus we live next to a water Easment. No leaking to my knowledge. Pics included
Any advice is greatly appreciated 👍
Welcome to the Bunnings Workshop community @slofire. It's brilliant to have you join us, and many thanks for your question about coating a Besser block wall.
Both bagging and painting with a texture coating can give a besser block garage a much cleaner, more finished look, but there are some important differences, especially when moisture is involved.
Painting with a textured coating gives a modern, uniform finish and is generally lower maintenance once applied. However, many textured paints are film-forming, meaning they create a sealed surface. If your blocks have ongoing moisture issues, this can trap moisture within the wall, potentially leading to blistering or peeling over time. To make this option work, you’ll need to address the moisture first—clean off the white residue (efflorescence) with a stiff brush and diluted vinegar, allow the walls to dry thoroughly, and then apply a masonry primer before the textured paint.
Bagging, on the other hand, is a thin render finish applied over the blocks. It has a more rustic look and, when done with a breathable mix (like lime-based bagging), it allows moisture to pass through the wall rather than being trapped. This can be a better option if you live near a water easement and are concerned about dampness over time. The downside is that bagging is less “perfect” in appearance, requires some skill to apply evenly, and may need periodic touch-ups.
Since you’ve seen moisture and some residue, it’s important to investigate where the dampness is coming from. Check that external drainage is working well, consider sealing around the base of the wall outside, and make sure there’s no groundwater seeping through. If the moisture source can’t be fully resolved, a breathable bagged finish might be the safer long-term choice. If it’s just surface moisture that can be managed, textured paint can certainly work and give you a more contemporary finish.
Please let me know if you have any questions.
Mitchell
Hi @slofire,
If you decide to go with bagging, you generally don’t want to apply a waterproof sealer underneath if you’re dealing with potential moisture issues. The main advantage of a breathable bagged finish is that it allows any trapped moisture in the wall to escape rather than being sealed in. Applying it directly to the besser blocks after cleaning off efflorescence (the white residue) is usually the better approach while you continue to investigate the source of the dampness.
If you later decide to paint over a bagged wall with a film-forming paint, that will indeed reduce its breathability and could trap moisture inside, leading to problems down the line if the moisture source isn’t fully resolved. If you want to add colour to a bagged wall but maintain breathability, you can use coloured oxides.
A waterproof membrane on the exterior of the wall by a professional is certainly an option and would give you a sealed, modern-looking surface, but as you’ve mentioned, it’s more expensive and less DIY-friendly.
It would be best to try to investigate the cause of the moisture before applying any coatings. Are you able to take some pictures of the exterior or the wall for us? Let me know if you need a hand uploading them.
Mitchell
