Gardener recommending putting lawn on a "membrane" is this right?

Hi, i have recently had all my border plants dug up but as i hadn't replaced them with anything weeds soon took hold.
Now i have decided just to get the borders all turfed, and have had some gardeners/landscapers come in to give quotes.

A couple have come back saying 7 days work to remove all the weeds and soil then lay the topsoil and roll the lawn out. (all manually)
But one came out yesterday saying he could do it in two days with a machine to dig out all the soil and replace it.
He then said he recommends compacting the soil then placing a membrane , then putting 150mm or topsoil ON the membrane and then rolling the lawn on top and claims it is to stop weeds coming through.

He said he's done it before and showed some pics, but i am sceptical as to how well the lawn would take and whether the roots can go deep enough.

Does anyone have any experience with this method of laying new grass?

 

What purpose will the membrane serve if it's under 15cm of soil?

 

I've seen some sites saying that 4" or less is bad as the roots don't have enough room.

But 15cm is too much?

So this is not a recommended method?

 

Once a lawn is established, it's very easy to keep it weed free. Regular mowing will largely take care of that. Grass has actually evolved to thrive when cut. Before us human sorts started working with it, it was wild animals grazing it that did the job.

Unless there's something really invasive like wild brambles there, stopping anything coming up from underneath is really a non issue, because it would have to get through 6 inches of soil, through the grass roots, and then have to compete with the much more vigorous grass for light and resources. I might be wrong. I'm far from a professional gardener. But it just feels like an expensive solution to a problem that is unlikely to exist.

The other thing is, if there's 6 inches of soil on top of the membrane, that's more than enough for pretty much anything to grow in, so you'll still have to keep on top of the maintenance either way.

 

They are all saying the same with regards to the soil and that because there are so many weeds in it they are taking it away, otherwise they would break it up and mix the existing with top soil.

They are talking about taking away two lorry loads of the existing soil. (which will be replaced by the top soil at the same level)

The area in question is 150 Square metres. (and there have been wild brambles in overgrown areas of the garden although since they were removed with the border plants they have not reappeared)

 

Only point of a membrane there would be to stop the top soil mixing with the soil below.
I can't think it would be a weed suppressant.
What kind of weeds are we talking about, deep rooted perennial ones or just annuals that have moved in since the ground has been disturbed.
Personally I think a few pictures would be good .
I really can't see why any soil would need to be removed.

 

It was cleared in March.

 

A lot of it looks like just annual weeds but there looks like some tree suckers or regrowth from the shrubs that were there before.

Wrong time of the year, in my mind to tackle this.
I'd wait till spring and hit it with glyphosate, then turf over, but means waiting until June next year before laying the turf.

 

Were these written quotes or verbal?

 

The first thing we need to know is if you can or wish to do any work yourself, either light weeding or heavier digging ?

Any soil thats been disturbed by removing lots of shrubs will bring a lot of weed seeds to the surface and in the warm summer they soon germinate and grow.

Normal weeding every few weeks by hand or with a hoe can overcome most annual weeds, but in the state they are now, even at this time of year would suggest either pulling them up by hand or using a Glyphosate spray to knock them back.
At very least, pull up any weeds that are in flower so prevnting then creating more seeds.

Putting down membrane , removing and replacing tons of soil is just a needless money earning job for the cowboys, bet they quoted you several thousands£ ?

One problem with putting new turf alongside an existing lawn is that it will always look different and rather obvious in our experience.

Assuming that you initially just wanted to avoid the problem of maintaining that border ? have you considered a much simpler option of removing the top growth of weeds as above, laying a weed suppressing membane on the soil, then adding a good layer of attractive gravel or shingle where you can leave it bare or use pots of plants or attractive ornaments etc.

 

Had a guy just come with a good amount of good check a trade references and he basically said what most of you have been saying.

No membrane needed and he can use the existing soil with a small amount of topsoil. Just needs to put a weedkiller down for a couple of days after clearing the weeds.

A lot cheaper too.

 

Not sure why he would clear the weeds and then apply weedkiller, also not sure what weedkiller works this late in the growing season and still allows replanting immediately.