Forum home› Problem solving
This Forum will close on Wednesday 27 March, 2024. Please refer to the announcement on the Discussions page for further detail.

Alternative to stones

KweeglyKweegly Posts: 104
in Problem solving

Hi All,

I'm thinking about making a green roof which will in affect be made up from many seed trays. I don't really want to put small stones in the trays as it will increase the weight. I'd much rather use an alternative at the bottom of the tray to improve drainage.

Can anyone suggest cheap alternatives?

Posts

  • LoxleyLoxley Posts: 5,698

    Interesting idea. How are you securing the trays?

    "What is hateful to you, do not do to your neighbour". 
  • KweeglyKweegly Posts: 104

    I'm building a lip around the roof which will stop them sliding off. I was thinking the weight would hold them in place. The trays are 6x4 and each hole is 75mm deep, with soil in they should be heavy enough to stop the wind moving them.

  • FairygirlFairygirl Posts: 55,117

    Personally - I don't think that'll work. You'd need a barrier/lip round each tray to stop them sliding, and the gradient on the roof would need to be very small - unless I'm totally misunderstanding your idea. 

    Is it a shed or garage roof? What's the overall size of it, and are the tray sizes in inches? 

    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • KweeglyKweegly Posts: 104

    basically my own version of this.

    http://www.sedumgreenroof.co.uk/sedum-mats.php 

  • Kitty 2Kitty 2 Posts: 5,150

    Is it a shed roof?  I think a green roof planting can be very heavy, some reinforcement may be needed. Also the covering/felt needs to be in tip top condition to prevent water ingress. 

    I've not done one myself, but have pondered whether shallow rooted plants like sedums would root and survive in a fabric type covering (eg. a coir doormat), with a sprinkling of soil.  ???  Probably another crazy idea image but I like diy stuff done on the cheap image

    What were you thinking of growing on your roof?  

    Edit: ah...sedums.

    Last edited: 25 August 2017 08:37:25

  • plant pauperplant pauper Posts: 6,904

    My friend's mum was nearly killed by next door's 12ft trampoline when it blew over the fence and it was anchored with guy ropes. First puff of wind and your 6x4s will be down the street. 

    What about anchoring them in place with mesh or wire netting over the top which would be invisible when the plants come up through. It would also negate the need to put holes or fixings in the roof.

  • FairygirlFairygirl Posts: 55,117

    Fair enough Kweegly, but I'm not sure your trays will be big enough. image

    First rough wind here and they'd be off down the road! I'd only try it with the matting. I reckon I could do that myself and have often thought about it for the shed, but the aspect isn't great for sedums.

    Kitty's right about the weight  on the roof. Are you confident the roof's strong enough?

    Kitty - I'd lay something like heavy duty polythene or pond liner for waterproofing the roof first, then the drainage layer of felt, or similar, for rooting. Sempervivums or sedums are ideal because they need very little medium to grow in.

    I expect your doormat idea could work, but they would be quite heavy too. You wouldn't want them crashing through on top of you when you're potting your cuttings! image

    It's a place where beautiful isn't enough of a word....



    I live in west central Scotland - not where that photo is...
  • Kitty 2Kitty 2 Posts: 5,150

    image I've no plans to plant my roof up, ladders & me don't mix image.   An old doormat dumped in "the working area", getting muddy from boot wiping showed signs of weed growth image.....that's what got me wondering if it would work.  

    I've got some creeping sedums and saxifrages that spread over paving with nowt underneath to root into, yet stays looking like a green carpet.  You can flip it back like a rug image.   All at ground level mind you, a wetter surface than up high. 

    I feel an experiment coming on image

  • KweeglyKweegly Posts: 104

    Thanks for all the idea and information.

    The building is a self built summer house, the roof gradient is very slight and the roof is held up buy 22 6x2inch wood joists spaced 26cm apart. Over the wooden joists there is chipboard, then a thick pond liner. 

    There would be a lip around the hole roof with a gravel boarder for drainage. I also think the trays will keep the weight down as there will be a lot of air space underneath them.

    I was thinking I would put a root barrier down followed buy the trays, each tray would have a light soil mix to keep the weight down.

    I really like the idea of chicken wire to hold the trays down.

    I want to grow wild flowers in the trays.

Sign In or Register to comment.