Roof Top Garden

After along time away it's time to share my experience of putting grass on a concrete slab and building a roof top garden....

The key to a successful roof garden is to ensure that you can satisfy the following:
 - have a strong enough slab to support the weight
 - have a sealed slab to ensure you don't create a damp problem below
 - have adequate drainage so you don't create a swamp
 - have adequate watering so it doesn't dry out

You need a free-draining soil which holds water - an oxymoron if I have seen one!

So why build a roof top garden?

Easy - lack of space, great insulator and grass feels damn good between the toes!

Following are the stages I went through to get it right...

Step 1. Design
I contacted Earth & Water to get a basic design and also to provide me with some VersiCell and Geotextile Fabric. Earth & Water can provide the whole installation service however I decided to build it myself to keep costs down.

"VersiCell is a lightweight, high strength modular drainage cell designed primarily for sub-surface drainage and waterproofing membrane protection or to form tanks for underground storm water infiltration or storage." "VersiCell has a 98% void area to total surface and the highest possible absorption rate anywhere along the module, ensuring continuous discharge."

For the soil mix and the soil strata layer FytoGreen provided me Hydrocell flakes and also the Hydrocell RG30 foam layer.

The design looked like this - with and added layer of solid Hydrocell RG30 foam on top of the Geotextile Fabric:

And in plan:

Step 2. Decking
The first physical work was to build a wooden deck around the grass area and give the required 250mm elevation above the slab for the soil and grass. Reticulation had to be built and pre-plumbed under the deck and an Edge Board was added to give the soil something to butt up against.


Step 3. Slab
Because the structure was in excess of 10 years old it was obvious that the slab was free draining and the roof had adequate draining off of the roof. The slab itself was well over engineered and was 350mm thick.

Step 4. Waterproof Membrane
To keep costs down I opted for a double layer of heavy duty builders film to provide the drainage. The membrane was duct tapped at the edges and penetrated underneath the Edge Board ro ensure that all run off made it out and under the deck.

Step 5. VersiCell Layer
The VersiCell layer is laid directly on the waterproof membrane and forms free drainage.

Step 6. Geotextile Fabric
The Geotextile Fabric must be laid on top of the VersiCell in order to stop and soil fine penetrating  and blocking, the drainage. The fabric must be laid up the sides of the Edge Board and tacked into place.

Step 7. Hydrocell RG30 foam layer
The Hydrocell RG30 foam layer acts as a water reservoir for the garden.

Step 8. Soil
The soil mix was as follows and was mixed using a cement mixer:
 - 0.6m3 of 12mm cracked pea gravel (18.8% v/v)
 - 1.4m3 of the Landscape Mix (44% v/v)
 - 1.2m3 of the Hydrocell flakes(37.5% v/v).
Total 3.2m3 which is 25% greater than the measured volume, but you need to account for particle integration loss and compaction. Weight is about 2T.

The soil was then carried bucket at a time up two flights of stairs to the roof. Thank you friends!


Step 9. Compact
Compact the soil with a roller


Step 10. Turf
Lay the turf on the soil and water in. I opted for Buffalo as it's hardy and with the extended exposure I think it's needed.


Step 11. Have a beer and watch it grow

Update:
Three months later and we are moving into summer. The grass is growing extremely well and the room below is now noticeable cooler!

Thoughts of a teenage boy

Laying under the duvet; camouflaged from the day.
Hiding safe from harms way whilst I lay.
Outside the world awakens to a new dawning.
And meanwhile all I am doing is yawning.
Yearning and conferring.
Up now; the sun is rising , windows open and music selected.
Traffic purrs and lights are reflected.
Deflected and conflicted.
I am alive and I will rise.
To face the day. Before my demise. 

Sorry I digress; now the rest.
The best?
Thoughts of a teenage boy bring me utter joy.
On a day like today; forevermore and throughout the toil.
A vision of play, fun and laughter.
Here, now and forever after.
Long days of sand and sun.
Endless summers on the run.

That was so long ago.
A distant memory of foggy glow.
Drunken nights through the haze.
Blinding sessions what went on for days.
Dreams fulfilled and memories forgotten.
But I will always remember the good times so often.
And thoughts of a teenage boy.

Daylight Saving

Here at Le de Ville House we have been in great discussion for many months now on the topic of the ‘Yes’ Vote in Western Australia. After three extravagant years of balmy summer evenings and blissful nights it has been the general consensus here that Perth was finally catching the tails of the rest Australia; let alone the rest of the developed world. One might call it progression.

Saturday’s defeat is nothing short of humiliation for the local population let alone the general public within Australia. It’s called Regression.

After much debate and a number of emergency meetings in Le de Ville it has become obvious that the problem lays not in the local population having their say in the referendum; moreover, the wider population not having their say.

The last decade has seen an enormous influx of migrant workers fuelled by the increasing discoveries of oil, gas and minerals within Western Australia. This expansion has led to the creation of a modern Perth community of expanding mixed cultures and nationalities. There is now a unique local resident build up that believe themselves to be transient however are in fact permanent. Although Perth may be ‘home’ these residents lack the right to vote.

One can only speculate the thousands of residents who do not have the right to vote but wanted Day Light Saving. So it’s time to make a commitment to the place that you live and become a Citizen. Make Perth your home and have your say. The Community of Le de Ville welcomes you with open arms. 

Le de Ville support Progression and Daylight Saving is Progression

Fucking in heaven

We were more than impressed by Fat Boy Slim's performance at Good Vibrations yesterday.

He played his first track like it was an encore.

And the visuals. Oh the visuals. We were fucking in heaven. 

Vicky Cristina Barcelona

At Le de Ville the Community are in love with the latest offering from Woody Allen. With his portrayal of his own screenplay shot in explicit detail he proves to us that life is for living and living outside of mundane normality. Cristina knew one thing and that was what she didn't want.

Here's to Cristina.

Showing at Luna - Leederville

Grrrrr...

Those good folk at Tiger Tiger can hone their absolute perfect skills from barista to bartender this week. Known for being such an arduous task in this back water called Perth; the Community congratulate their success on gaining a liquor license and will be frequenting the lane daily. So it's time to move on from single origin day and up a notch to Hendrick's and cucumber. See you at there!

Deux Jus

After a day in the sun; faced with the heat of the night, here at the Community we have decided there is no better way of eating out today other than revisiting Jus to ensure that yesterdays burgers were not a fluke.

And success! They are not! Go the chicken! Go the fish! Delights all round the smiling table.

Can man kind live on burgers everyday?

Hugh Hefner welcome to the Community . . .