Preparation for new lawn where concrete was.

[NickH95]

Hi there,

I have moved into a circa 1950’s house and my next project is tackling the garden.

There was an old detached garage which had the roof removed due to asbestos. I have since knocked this down and removed and begun knocking up the concrete base, the plan being to turf/seed over this.

Under about 6 inches of concrete I’ve now found massive rocks/concrete slabs I’m not ever sure and I’m in the process of removing these too.

My question is, how do I get this area ready for new grass? And how much of the this concrete/hardcore do I need to remove? Do I need most rocks gone?

I’ve already filled one skip and will be getting another, so I just want to know what the end goal should be.

Hopefully attached pictures help.

Thanks in advance.

 

[Mr Chibs]

Depends on how good a lawn you want... I'd say you need to remove all the concrete, scrape back and get rid of all the big bits, then put some new top soil down.

Are you seeding or turfing?

 

[NickH95]

Thank you - obviously would like it to be the best possible so I’ll keep removing the big stones/concrete. How perfect do I need to get it before topsoil? I can put as much topsoil as necessary but do I need to remove all stones?

I’m not sure tbh, haven't decided whether to seed or lawn. Open to suggestions on that.

Thanks.

 

[Odds]

You'll need some loose stone/gravel to help drain the area and the finer you can make your topsoil, the better your lawn will be. Raking is key. Sieve it, till it, rake it until you have as fine a tilth as you can make it.

 

[NickH95]

Okay I’ll remove as much of the stones as possible.

How deep should the topsoil be? After removing all the concrete I probably need to being the level up by a foot. Should this be all topsoil? Or can I put something down first?

Thanks.

 

[lostinthelight]

The only way you'd be gaining by removing more rocks would be if you could get some contact between the the new topsoil and underlaying soil . I reckon your foot of topsoil would be ample , I bet there are not many lawned new builds with that much soil .

 

[Old Salt]

I had about 6 inches so your foot should be fine.

 

[scbk]

Looks a good spot to build a shed

 

[JohnD]

If you have a lot of broken concrete to remove from the first foot, it would be worth buying a motorised Rotary Sieve (Trummel/Trammel/Drum) which can sieve them out and tip into a sack or barrow. I've tried manual stone sieving, and it is hard.

If you hire one, break up the soil first to reduce hiring time. It is easier if the ground is dry as it crumbles better. If you have a dry crumbly tilth you can level it with a lute, which you can make yourself.

Grit is good in a lawn. Keep some back for top-dressing to level out the hollows that will form within a year.

Is your ground clay? Sandy? Chalky?

You can lighten a clay soil by working gypsum into it, which helps it form a crumb. Yes, I do mean plaster.

If your site is prone to waterlogging, you can dig a French Drain round the perimeter and fill it with clean broken stone and grit. Or a soakaway for ru -off from your shed gutter.



There is also a manual version suitable for small jobs like potting or a flowerbed

 

[Odds]

Just a thought but i like to keep some broken stones to use in a rockery: concrete hardcore is great as the pockmarked stone provides a good place for moss to form and spread...