Imber Akse House – Burlington’s LEED home

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.

Our house has taken the final shape and size. Thanks to the fine work of the framing crew and of course the effort of the Branthaven design team, our drawings turned out very true to plan without compromise.

Even with detailed drawings, having time to be on site regularly provided us many opportunities to identify potential issues before they came up. More importantly, spending time in the house at this stage prepares you for more detail at a later date.

The 2nd floor is moving along and the final look of the house is taking shape sculpturally. We’ve dreamed, lived and breathed this house plan for so long now that looking at the structure and walking around inside feels like we are taking a walk inside our own heads.

There are a number of passive cooling and heating methods our house will utilize to reduce the need to mechanically condition the living space. One main passive system is the breeze maker or lungs of the home.

The center main floor of the house is flanked front and back with sliding patio doors that can be opened on nice days when interior temperatures are higher than exterior. In most homes, exhausting this warm air quickly can be a problem. With the design of high ceilings throughout the breeze zone combined with clerestory windows at the 14′ ceiling height on three walls, the rising hot air is allowed to escape which in turn does two things. Firstly the rising air creates a low pressure zone on the cool mass floor, pulling air along the floor from other areas of the house as well as any open doors. Secondly the rising and escaping air creates an interior low pressure that should pull in large volumes or exterior air from the patio doors. Depending on the primary wind direction and which doors are opened relative to time of day and shade, we can create a breeze of cooler incoming air.

Since air movement changes the relative feeling of temperature, we should stay comfortable longer with just cool mass floors and exterior air temperature.

If you ever want to feel the meaning of footprint in all its emotional and physical impact – build a house. We have forms. With it we can see the beginning of the home take shape in terms of proportion and scale – an amazing feeling of reality and familiarity with a floor plan shape we’ve stared at for years on paper now sitting in the ground at hundreds of times larger than we’re used to seeing. Tomorrow, concrete.

You’d never think a hole in the ground was so exciting. Yes, it is. Foundation digging started today and should complete in another with forms arriving sometime day 9. As we expected from the Soil Engineer’s guestimate, there is water sitting on clay. Consequently we will be using a series of technologies to keep the basement dry. First under the slab we’ll use a system of water collection tubes to direct the flow away or toward the two sump pumps. See system plan by AMEC. Next, the walls will be sealed and insulated from cold and moisture using Tremco’s TUFF-N-DRI® Basement Waterproofing System. This system dissuades water from sitting against the absorbent concrete foundation wall and moves it down and under the floor slab into the tubes.

The foundation walls are also sealed with Watchdog Waterproofing making them impervious to moisture. The combined system apparently provides a thermal break of R12 from the grade down. This combination should guarantee the basement is dry for at least 10 years. What? Only 10 years? This is the sad state of basement guarantees – if you believe you’re about to get better, read the fine print.

Irony. Tear down an old house, weigh all the stuff that you toss, recycle what you can and then commend yourself for what you diverted from landfill. So let’s. Apparently we diverted over 80% of the demo from Landfill – and this is good. Really though, destruction aside, waste diversion, or avoidance, is a key to efficient construction and should be achieved in a number of different ways starting with building simply.

Complexity leads to waste, in odd cuts of materials, re-dos, or excess layers of finishes, veneers and hidden materials. Mike Leyer, our build foreman might have a alternate view on our “simple” house design however.

Next, use everything for something. Since we are all amazed at how much material could be recycled from the demolition, imagine how much easier it is to use the waste from new materials. The secret is to plan ahead — choosing materials that are recyclable (cut studs used as framing blocks or cabinet filler) or at least down-cyclable (off cut studs sent though the chipper as mulch). Next a waste plan is needed to ensure material waste is sorted when created, not later. Later means labour waste and labour waste is money burned and that means… (see Sustainable Costs)

Don’t invite waste. While working with a client on green initiatives, we looked at their waste problem and suggested something simple to us but apparently revolutionary to them. “Hey, don’t invite waste by allowing suppliers to bring more than they need and certainly no packaging”. What this means is every time an outsider from your site or company brings a coffee cup, lunch, packaging for their material or good, or excess beyond what’s ordered, you have to deal with it and it costs you and the environment. It’s easy. If they can’t bring it, they won’t. And if they can’t bring it they’ll change their policies to deal with their wasteful ways – perhaps by initiating methods for delivering goods sans package, or in re-suable containers. The dam of resistance forces pressure upstream.

Certainly if they are forced to take back packaging and incur the cost of waste, one of a few things will happen. They will reduce packaging to reduce costs. They will become efficient at recycling waste from packaging as an economies of scale will be achieved. They will begin to develop products that don’t require packaging or overages. And, they might even start carrying a travel mug.

Build with prefabricated materials. This is a way to combine two ideas – a supplier that plans, brings only what they require as per your design and doesn’t need packaging. Pre-fabricated house components are a growing trend in building with everything from radiant floor sections, walls (SIPs), foundation components (ICFs) and even entire house sections. The idea is that from plan, sections of the home are made off-site with precision in ideal conditions using labour achieving an economies of scale. The finished components are shipped to the site and installed in less time compared to building from scratch in less than ideal situations.

Our goal, and the goal of LEEDs, is to have very little, if any, material waste enter or leave the site. Except for those appliance boxes we’ll convert into condos for the kids.

Years of dreaming, planning, designing and preparation and we’re finally here. Demolition day – the beginning of a schedule to build our home. We watched the bullish efficiency of the demo and could only think – we’re committed now. Hopefully the remainder of the project will go with such apparent confidence and ease.