I am a "cement newbie" currently repointing my patio flags. Current mortar pointing is breaking up and weeds are getting through. I am using ready mixed Rugby mortar (not fast setting type); just add water. I tend to rake out and redo a small patch each evening when the sun is fading. Quite pleasant work really.
A few questions:
- Mortar mix -- stiff/sandy mix is easier to brush clean but is harder to work with; wetter mix drops straight into the gap, but can get onto flag face. Which is best?
- Do the flags need any expansion gaps left at the edges? Compared to repointing using sand, say, repointing using mortar gives a less flexible joint.
- I have read a few horror stories about such repointing tasks failing quite quickly due to the mortar drying out. As a newbie, should I leave this until the cooler weather?
bruce