Following a few weeks of freakish weather – heat, cool, daily rainstorms, hail like I’ve never seen in my life – the roofing contractors finally we’re able to install the TPO Roof Membrane! And beautifully. This means the interior work can now begin safely!
TPO stands for Thermoplastic Olefin or Polyolefin, a roll sheet material that is unrolled, and in our case glued to the roof deck and hot seamed using special irons to ensure a pool liner like continuous membrane. For flat roof applications like ours, it doesn’t get much better for the cost. Of course there is arguably better performance with some other technologies like “Liquid Plastic” but when compared to cost vs. minimal improvements, this is the stuff.
Aside from great leak protection, the TPO provides:
+ great UV resistance
+ excellent puncture resistance, but it’s not a dance floor
+ long term puncture repair-ability
+ responsible light reflectance
+ reasonable “green” factor when compared to other roof technologies
+ effective root membrane for living (green) roofs
In a practical sense the TPO roof was chosen for many reasons that can’t be understated. Firstly the white colour simply doesn’t collect heat in the summer. That means a cooler roof above and below the surface. Recently Toyota Canada installed this surface on one of their plants and saw an 8ºC performance increase in their cooling. That’s huge when you consider the goal is a 24º setting equating to essentially 30%. While showing the roof to a friend, we stood on the 2nd floor deck at noon when the sun was blaring. Though the air temp was just 20ºC, a regular black roof would have been unbearable, but this surface was still feeling like 20º though we needed serious sunglasses. The nice thing was that just inside the house, there was absolutely no warm air blowing in from the surface.
Secondly the white roof colour reflects light (not heat) into the house through the clearstory windows and illuminates the rooms. It’s really spectacular. Have a look at the two ceiling shots and see how well they are lit up considering the shots were taken at 7pm. This should equate to a major reduction in our need for artificial lighting during the day and evening.
Lastly we hope to install a living roof in some sections which with most surfaces would require a special root membrane of inorganic material to resist the plants from breaking down the surface and causing leaks. The TPO is an excellent root membrane so with the additional load capacity we’ve design into the structure, we can freely add to the green roof as we need to.
Maintenance on the roof is simple – keep it clear of debris and give it a wash once and a while if you don’t like the gradual staining due to our dirty cities and blown organic material.
Following the roof membrane, the next stage has been windows. Over the last couple of weeks, Pella has been carefully installing all of the glazing with only a few more to go. We’re loving this stage, the quality of the product is excellent, beautiful to look at and they have really done a lot to frame the building and bring it into proportion a little more.
