Comparison test: hot mud vs taping mud on a ceiling repair

I did a side by side test on my garage ceiling last month - one half with 20 minute hot mud and the other with standard all purpose taping mud. The hot mud sagged like crazy on me and was a nightmare to sand, while the taping mud went on smooth and barely needed any sanding. Any of you guys stick with one for ceilings specifically or is it all the same to you?

2 comments

2 Comments

davis.dylan2d ago

I patched a 4-foot ceiling crack with 90-minute hot mud and it hardly sagged at all.

riverowens2d ago

Kind of wild that nobody's mentioned how that hot mud's working against you on a ceiling patch like that. @davis.dylan hot mud sets fast but it can shrink back and crack worse than all-purpose joint compound on a long seam like that. I've seen guys do that exact thing with 90-minute and end up with a hairline split right down the middle a month later because the chemical reaction pulled tight. All-purpose gives you more working time and flexibility for long cracks, especially on a ceiling where gravity's already fighting you. Your mileage may vary depending on temperature and humidity, but I'd never trust hot mud on anything longer than a foot or so overhead.