On May 20, 3:57*pm, jjb20 wrote:
Help... I have recently laid new turf and someone said it would be a
good idea to lay a permeable membrane before putting down the
topsoil... 4.5 tonnes of topsoil for 60m square. I stupidly took their
advice and laid down permeable weed control fabric. I’m worried now I
don’t have enough soil depth for the root to bed in. please help! Will
top dressing help build soil depth??

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jjb20

You don't tell us the most important thing, which is how deep it is..
If you have 4" of topsoil before the fabric, you should be OK. 6"
would be better. Topdressing will eventually build up the soil, but
it will take many applications over time. I don;t know whay anyone
would tell you to put down weed control fabric under topsoil. It is
intended to go on top of the soil, and under mulch or stone to prevent
weeds in beds.