Sedums for the Main roof

Sedums on the Main Roof

The next two days were the culmination of almost 14 months of dreaming and scheming , hatching and planning, designing and organising and grunting.  It seemed like a long flog but we were looking forward to its end.  

The sedums for the main roof arrived on a big truck with a extendable boom like a HIAB crane.  It could reach up about 40 feet and could swivel its forks around.

I need to apologize for a complete lack of pictures here as my brain faded completely. Si you'll the thousand word version.

The product we installed from Xeroflr was their XF301 Sedum mat.  It is a field grown product.  It was delivered on a Connons truck so I assume it was grown by Connons on one of their Waterdown farms.

It was based on a layer of drainage material weave side up that had one layer of water storage fleece below it.  The open weave of the drainage material was filled with GM (growing medium) into which a range sedums had been grown.  By my count we have 8-10 species, although a couple predoominate.

The mats came rolled in 1 m by 1 m sections. Each roll was 1 m long by about 0.4 m in diameter, weighing about a gazillion pounds. About 40 or 50 lb.  Quite heavy and unweildy. They were delivered with 54 sq m ( about 550 sq ft) rolled up on two pallets.

Aknwloedging the reach of the crane, we elecete to lift them in batches of 6 -7 beacuse that matched the distribution of our temporary staging zone / landing pads.

S, with teh drivers help we rebundled the rolls intoa spare pallet and starting hoisting them up toteh roof. Whih took a couple of hours.

Then, with the trusty support from my able assistant (son, 28) we unrooled the mats and fitted them on top og the GM.  This brought t top of the installation up to be about 1/2 in above the level of the perimtere rail. Which felt fine to me.  

There was quite a bit of cutting and fitting to manage the smaller areas and shapes.  Initially I used a pair of scissors, for about 2 inches.  Then I tried a heavy duty Excato style knife and used a fresh blade every meter.  The GM is very bluntening. I would run out of blades very quickly. 

The solution is a 4" size angle grinder hired for the day or two.  

It was fitted with a "crack chaser" blade.  Did a really good job of cutting through the felted base material and the woven GM carrier.  Worth at least $40 a day!!!

To their credit, Xeroflor did ship a few more pieces than were strictly ordered, so we were able to sift and pick through the shipment to get really good mats for installation.

The sedums did come out looking floppy - flat and jaded - not unexpected from rolled material that had been scrunched into a roll then bounced at the way to the installation site. As part of the installation process I gave them all a good watering and they picked up substantially over the next couple of days.

So here is how it looked after we finished the installation.

Main roof open area

Up on the top of the 3rd Storey Walkout - close up.

Up on the top of the 3rd Storey Walkout.

The northern edge is tucked underneath the solar panels.

In some locations the GM filtered through the sedums.

Well, that's it. Jobs over. 

Over the next few months I'll put up some photos to show how it develops.  I'm hoping that the areas with GM showing will diminish as the sedums really start growing.

And I am looking forward to a cool summer.

For people who are interested in further discussions I suggest you leave a comment and I'll get back to you. We can remove the comment later to keep your coordinates relatively quiet. Or contact me via Facebook.
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Green but not living...

Poor Mans Green Roof!

There was a break of a few days between the hoisting of the growing medium and the arrival of the main load of sedums.

Winds were forecast.  As I didn't particularly wish to turn WIllowdale into a Saharan dust storm I applied one unit of green roof.

Green:  Ex Home Depot.

Ballast - courtesy of neighbouring building site  - on short term loan....

Hoisting the GM

Hoisting the Growing Medium (GM)

Following the installation of the edge railing, the next layer to be installed was the drainage layer. It was the same highly porous open weave material as was use don the kitchen roof.  It cuts with scissors and is laid with the grey filter fabric side facing up.

The next layer was a double layer of the water storage cloth.  While the open areas are pretty straight forward, the multitudinous corners took a lot of dovetailing and other finessing to ensure that there were no pathways for the GM to sluice through.

Wide spaces are quick and easy : two layers set perpendicular to each other.

Corners take a lot more finessing to ensure double coverage.

Corners are quite time consuming and fiddly.

And then the BIG DAY comes ... to hoist the growing medium.

It's a big day because this was the first of only two tasks that I could not do myself.  I needed heavy machinery and operators.  The GM was delivered in 1 cubic yard totes, each weighing about a ton.  In hindsight we were lucky to not be using the SOPREMA GM which is delivered in 4 yard totes - destined for large areas like condo and factory roof tops.

Growing Medium is NOT soil.!! No one says what is really in GM, but Xeroflor describe it as a proprietary mixture of lightweight, mineral based materials; including porous aggregate and organic matter derived from composted plant materials.  It is more mineral than organic, so it won't break down and disappear to quickly like soil would.  Our GM had a noticeable red hue to it from crushed brick material.

The sizing of the GM was in the grit to fine gravel range. All sub- 3/8".  Very little in the clay-silt-fine sand sizings.  Not all all well sorted.

Here is a post -hoist photo of rain-washed growing medium.  It has a distinctly red hue from the crushed brick component.

In our installation we planned to use a 4" (100 mm) layer on the main roof, amongst the solar panels, with a 6" (150 mm) layer of GM being used on the roof of the 3rd storey walkout.  

Why 1 ?? Because that's all we could reasonably hold within the structural limitations of the roofs.

Why 2?? Because a thickness of GM would provide additional water storage to reduce the frequency of watering.

Why 3?? Because we might elect to broadcast some native plant seed next spring, and they grow better (more reliably) with some GM into which they can stretch their roots.

Then the issue is how to move about 6 cubic yards of this stuff up 25 (8 m) or 35 ft (11.5 m).  My back was not that strong.  However Lino's loader was. 

Our neighbours were building a home and friend Lino,  the framer, had a "zoom boom" that was rated for 1 ton up 42 feet.

Lino's "zoom boom" without which we would have been skunked, and substantially poorer.

Lino is always good for a challenge, and came over in the evenings to help out.. We put totes destined for the highest roof 35 ft (11.1 m) onto a pallet and then hoisted it over the edge of the roof.  The totes for the main roof, at its lower elevation of (only) 25 fee,t were hoisted by their own straps.

The active end of Lino's loader, from the top, down about 30 feet..

I then cut away the side or bottom of the tote so its contents fell gently into a temporary hopper.  From there we shoveled it out around the roof with snow shovels, raking it into place but not compacting it particularly.

GM spilling gently onto the 3rd storey walkout roof.

Temporary hopper that holds about a yard of GM . We then shovelled it around the roof with grain / snow shovels

Getting started.

Vital tools

This funny looking jut-out is to provide space for the adjacent electrical control box to be opened.  It has the circuit breakers for the individual chains of solar panels and might be needed for SP maintenance: assuming you can still open it.

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Almost there.

Finished, ready for the living layer.
The GM is finished off about an inch below the top of the edging, by design.

Raked, but not compacted.

What does hoisting cost?.  Depends!.  Buddy rates are negotiable.

Commercial rates for a crane truck that could lift 1 ton about 40 feet "up" and 10 feet traversely ("over") run about $165 per hour (Ontario, 2014) : four hour minimum, including all travel time.

Our dilemma was that we could not hoist all 6 yards in the same session as we did not have places to temporarily stage them within reach of a regular crane truck. In the end we did it in 3 separate sessions based on 3 different staging areas.

 A substantially bigger machine would have been needed to increase the dimension of the traverse distance covered.   We needed to hoist 1 ton  30 feet horizontally at 40 feet vertically.  A bit of a challenge $$$$$$!

Friend Lino and his marvellous lifter fitted the bill wonderfully.

Railings

Edge Railings

The edge railings are based on "L" shaped aluminium extrusions.  They are used on the perimeter of the installation to contain it, provide a nice edging, and prevent  the growing medium from sloughing away or resting directly in the structural elements of the home ; walls, parapets.

Edge Railing

The material we used is the Xeroflor XF510 "XeroEdge" product.  There are likely others in the market place.  The slots at the base of the vertical plane are for drainage.  It is available in a range of heights : we used the 4", 7" and 9" varieties within our installation.  This material comes any length you want, so long as it is 10 feet. However, if you are careful there will be very little wastage or scrap left over. 

It comes with neat little U-shaped joiners that slide up underneath the top lip of the channel and are simply and quickly attached with PK or self tapping screws (supplied in abundance).  The trick is the make sure that your joins are always in the middle of long runs, and never in the corners. In practice I ended up attaching the joiners to the vertical face first and then put the vertical screws in the top second. Whole lot easier to hold / faster to complete.

A word to the cautious: be careful to vacuum up all your aluminium shards created by the self-tapping screws lest that puncture your root barrier, protective layer and roof membrane.

Our main roof installation was a bit complicated by the highly irregular shape of the solar panels plus the walking pads.  There are a (large) number of short elements plus some longer runs.

I tried (initially) working with one large DWG.  That didn't work out at all. I ended up (re)measuring / cutting / installing each edging section in succession : 10 feet at a time.

First you measure, being careful to identify the "inside" corners where a V of material will need to be removed, and the "outside" corners where a simple cut suffices. In fact, measuring twice helps. I worked to 1/4" units and was not caught out too badly.  Here are a couple of typical sketches used.

Working DWG

Another Working DWG

The "outside" corners are straight forward in the you just cut through the horizontal plane and then bend the vertical plane around the Z axis.  I used a  40 tooth "aluminium" blade in my 7" size circular saw to do all the cutting.  Then hand filed all the sharp / arris edges smooth. Then bent it by hand.

The "inside " corners take more work as you need to remove a 90 degree V shape (100 deg is better) form all the horizontal planes before you cab bend it. Although this material can be easily cut with "tin snips" you will need both left handed and right handed ones to  most easily / quickly / neatly deal with both sides of some of the cutting.

An "inside" corner marked for cutting the V out of the horizontal plane

A very typical section showing, an "outside" corner, then an "inside" corner, then another "outside" corner. bent, ready for installation 

Another example of one section. all bent into shape ready for installation

Yet another example of one 10 foot long section, all bent into shape ready for installation.

We used over 30 sections of railing.in our installation.  Only two of them were used "straight".  None of the others were the same, or even slightly resembled another.

The fabrication of the edge railings was very tome consuming.  With all the measuring in the roof, then marking in the garage, then remeasuring on the roof, then cutting, snipping and filing in the garage  took an inordinate amount of time.  About an hour per length, at least, and two hours for the complex ones.

Here is a selection of photos of the actual installations.  The black layer is the root barrier.

At a couple of places, the living roof is installed underneath the cantilevered solar panels.

The vents from the house sewers received their own edges.

This shows the roof of the 3rd storey walkout.  The edge railing is 9" high and shows shaping around the drainage outlet on the LHS to accommodate rock salt for winter melting. Half a bag of rock salt in the early winter will keep the drainage way open through all sorts of snow and ice.