Schoolhouse Build Day – Roof Planter and Art Posts

Posted on: October 21st, 2010 by Heather

Since the first post we have gone from concept to implementation. To recap this project, the client Mark Shieh of Take Roots Properties Inc. is interested in three changes to his schoolhouse converted condo. The first change is to have plants growing on the roof for both visual interest and inspiration from inside the building and on the street. Second, to install art posts to support a local art alley project and third, to add garden walls and a gathering space to the front yard.

We started the design process by meeting on a bi-weekly basis to discuss possible design solutions. Each meeting was a fruitful design session where we honed and clarified goals and how the design would meet them. This project involved tackling a lot of issues that we hadn’t previously worked with, such as designing with metal and building rammed earth walls. To help with metalwork design and production we quickly retained the help of a volunteer metal worker Faith Dempster. To explore the rammed earth possibilities we made use of PiPer and landscape designer, Tenille Ziegenhagel. Tenille researchedrammed earth construction methods and coordinated a rammed earth construction test to assess our ability to use rammed earth and the value of employing this technique (rammed earth blogpost coming soon). Due to time constraints we have decided to make the rammed earth a second project that will take place in the spring.

In the short term we decided to focus primarily on the roof planter and art posts.

The goals of the planter are to:

  1. Plant grasses and flowers on the roof to create visual interest for people at street level and from inside the condo units and inspire people to think beyond the status quo.
  2. Build a sleek, durable, and low-maintenance roof planter to be enjoyed for many years to come.
  3. Demonstrate the value of native species for use in a roof garden both for their beauty and seasonal changes, ability to support animal life and for their low-maintenance requirements.

The planter is 54’ long,16” wide and 6” high. After much design consideration it was reduced to a simple trough made of 2 pieces of facing 6” x 6” x 3/8” aluminum angle. There is a 4” gap between the facing pieces to allow for drainage and the trough rests on frequently placed stacks of shingle. The planter is secured to aluminum bars that are anchored into the dormer wall in case of high winds or earthquake. We chose aluminum for its appearance, workability and durability. One issue that arose in this process was the potential of metal reactions between the fasteners and the aluminum planter causing corrosion or galling. Since our fasteners will be sitting in a permanently moist condition beneath the soil we decided to use stainless steel nuts and bolts and apply a silver anti-seize in order to isolate the metals from each other.

The goals of the Art Easels are to:

  1. Create durable posts that will last for decades to come.
  2. Be artful in their design and arrangement.

We planned 3 I-beams to stand like art easels in an interesting composition. Each easel is made of a 6” wide I-beam and has been fashioned a unique face and personality.

This past weekend on Saturday, October 16th we had beautiful weather for the build and a fantastic volunteer group of residents, interested neighbours and PiPers.

The volunteers worked at lightening speed cutting and installing the liners, such as a mesh base, filter fabric and water retention fleece. We then laid a 1.5” base of perlite and topped that with a 5” mix of potter’s soil. This design is intended to drain water during the rainy season and retain it during the dry summer months. The placing and planting of plants, while somewhat more time consuming went smoothly.

1. Mesh 2.Filter Fabric 3.Water Retention Fleece 4.Perlite

The plants were sourced from Nats Nursery in Langley and include grasses, sedums, moss and bulbs. The plants were generally chosen for their native or near native status, sun loving nature, drought tolerance and mostly short stature as to not obstruct views from the dwellings. The plants include:

Berkeley Sedge – Carex tumulicola
Elijah Blue – Festuca ovina
Red Fescue – Festuca rubra
Idahoe Blue-eyed Grass – Sisyrinchium idahoense
Fools Onion – Brodiaea hycinthina
Stonecrop – Sedum acre
Angelina Stonecrop – Sedum rupestre ‘Angelina’
Scotch Moss – Sagina subulata ‘Aurea’

Additionally, 3 more striking wild flowers will be planted in late fall or early spring.

Common Camas – Camassia quamash
Scarlet Paintbrush – Castilleja miniata
White Fawn Lily – Erythronium oregonum

Based on cost and availability we planted small 1.5” plugs to 3.5” and 1 gallon pots. Now it’s time to wait and see how they do in their exposed and potentially harsh rooftop location. Since the planter is on the east facing side it will hopefully get adequate rays while avoiding the scorching afternoon sun.

The anchoring of the art posts went well, however we decided to hold off for another day to place the last post, which will also hold the sign for the Strathcona Art Alley. We plan to finish placing the last post in the coming weeks.

It’s been a pleasure working on this project and much thanks to our dedicated design team Bryce Gauthier, Mark Shieh, Faith Dempster and Tenille Ziegenhagel.

img_4612-small1 img_4586-small group-on-roof planter-assembly