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Ask your QuestionWhat is best to put underneath flagstone when placing them onto an old lawn. I have removed the turf already, but unsure of what to lay underneath the flags?
Asked by Dorothy on 25th Aug 2021"You will need a sub-base of mot type 1 about 4" to 6" depending on traffic over the top of the flags."
Answered on 22nd Sep 2021 - Member since Feb 2018 - report"If you want the patio to last as long as possible you will need to lay a good membrane, then lay and compact some type 1 hardcore and then the same with sharp sand. You will need a good sub base if it is a high traffic area or you will end up with movement and subsidence over time."
Answered on 31st Aug 2021 - Member since Aug 2021 - report"Hi, the best is type 1 stone, laid and compacted, at least 100mm deep."
Answered on 29th Sep 2021 - Member since May 2019 - report"Type 1 mot. Hardcore then compact with a Wacker plate, then lay on a full wet cement bed or sand and cement mix."
Answered on 20th Oct 2021 - Member since Oct 2021 - report"For flagstones, you have to put a membrane down and then lay the stones in place.
Thanks"
"You need to put type one down and compact it before you lay any slabs on it or they will just subside over time."
Answered on 25th Aug 2021 - Member since Jan 2020 - report"I use type one down then go over it with whin dust or sharp sand won't move"
Answered on 25th Aug 2021 - Member since Aug 2021 - report"You need to at least put down a membrane, it’s like a plastic material and or also some sand, ask any good builder's yard for sand to put down under flagstone or slabs and they’ll get you some for your project."
Answered on 25th Aug 2021 - Member since Jul 2021 - report"You should dig out an extra 100mm to allow for a 50mm sub base use mot type 1 and a mortor bed of 50mm to secure the slab from movement"
Answered on 20th Sep 2021 - Member since Sep 2021 - report"Aggregate base and membrane is needed to lay a patio on."
Answered on 26th Aug 2021 - Member since Aug 2015 - report