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- 8 Jul 2024
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Have a situation where I've reboarded the ceiling overhang in my house. Originally it was two plasterboard layers with ordinary plaster and white outdoor paint for waterproofing. I can say that for a 50yr old house there were minor hairline cracks and no issues with damp or mould; ripping it out there was no weakness that implied moisture degradation. I've decided to replace with thicker and denser plaster board and over board with cement board for better soundproofing and water resistance (incase I want to wash my car in the driveway). Now I'm stuck on what to use for render.
The obvious best choice would be silicone render but that is very expensive to apply, especially for such a small area and seems like it would need some skill. It's not easy to change colour or repair. Out of the question for me.
I was originally going to use OCR system from B&Q to avoid the hassle of creating my own mix but it states not applicable for cement board and where there is risk of movement.
Alternatively, I was thinking I could do plastering sand and cement (4:1) with sbr mix, no board priming, just a bit of water to tame suction but leave enough so it doesn't fall to the floor. The sbr would act as the waterproofing agent and maybe give more flexibility? I'm not afraid of using lime either, just don't want to buy 25kg bag and use hardly any.
I've read acrylic render could work but the only suppliers I can find are online and I haven't seen that much online about it either / doesn't seem like a popular option. Why not?
My question is, considering how well the original setup lasted, and that while it's outside it's not truly exposed the weather, could I get away with the OCR system? What render system would you recommend or how would you go about it?
Cheers,
glnovice90
The obvious best choice would be silicone render but that is very expensive to apply, especially for such a small area and seems like it would need some skill. It's not easy to change colour or repair. Out of the question for me.
I was originally going to use OCR system from B&Q to avoid the hassle of creating my own mix but it states not applicable for cement board and where there is risk of movement.
Alternatively, I was thinking I could do plastering sand and cement (4:1) with sbr mix, no board priming, just a bit of water to tame suction but leave enough so it doesn't fall to the floor. The sbr would act as the waterproofing agent and maybe give more flexibility? I'm not afraid of using lime either, just don't want to buy 25kg bag and use hardly any.
I've read acrylic render could work but the only suppliers I can find are online and I haven't seen that much online about it either / doesn't seem like a popular option. Why not?
My question is, considering how well the original setup lasted, and that while it's outside it's not truly exposed the weather, could I get away with the OCR system? What render system would you recommend or how would you go about it?
Cheers,
glnovice90