Building the Ontario Cottage

Deciding to build a cottage in Ontario comes with many tough choices that can saddle the owner with onerous utility bills for generations to come when really, they simply want a reliable place that enriches family memories or to celebrate their golden years in comfort. Yet all too often, owners unwittingly get pigeon holed early in the design stage into installing complex mechanical systems that at first glance look like a good choice, but often prove to be very expensive to operate, maintain and install.

The current trend in designing cottages is for that modern look with lots of floor to ceiling windows that face the lake – even if the lake is north facing – and the wants list looks like this:

  • Modern look
  • Floor to ceiling windows facing the lake
  • Wood burning fireplace
  • Ground Source Heat Pump for heating & cooling

Thus begins a cascading series of decisions that can have a huge effect on how you’ll spend your money after the cottage is built. The second point throws a wrench in the works as windows don’t perform as well as insulated walls and when we replace insulated wall area with glass area that loses warmth far too quickly in winter and lets in lots of heat in summer and winter in some rooms; it challenges the mechanical system.

How’d We Get Here?

Which is why we take issue with the last point- its not the only way. Curiously, the Ontario Building Code will have a huge impact on the completed design if not reducing the window area below 22% of total wall area, then forcing the hand of the owner to go with Ground Source Heat Pumps (GSHP) if no natural gas lines pass on the street. And though a good GSHP works well for both heating and cooling, there are usually many shortcomings and one is that in really cold months, a GSHP system will use electric resistance heaters as a back-up system – which is the most expensive way to heat a house and only stands to get more expensive with time.

Heat pumps use electricity, but unlike electric resistance heaters that “burn” 1 unit of electricity to make 1 unit of heat, the magic of heat pumps is that the electricity doesn’t make heat – it moves heat. In fact, a heat pump moves heat so efficiently that 1 unit of electricity can make 3 -4 units of heat. In winter time, the GSHP moves or pumps heat from one place (outside) to another (inside) and in summer the heat is moved in the other direction.

Next is the crediting of efficiency in the eyes of the government approved software used by Certified Energy Auditors who do calculations on your cottage design as part of the permitting process if you have more than 22% window to wall ratio. The histrionics on this topic are interesting as electricity has always been seen as the more “green” option when compared to a fuel like natural gas, so that with energy modeling software, electrical systems will have a “better” EnerGuide performance score than other fuels that don’t rate as 100% efficient even though the electrical generation plant, transmission and its grid distribution systems are far from 100% efficient.

Are you Dissing Ground Source Heat Pumps?

It’s not that GSHPs are bad, it’s just that unlike a furnace which has a factory set efficiency, a GSHP is a unique piece of machinery with pumps that need to work with the fluctuating conditions outside and is designed by one person – who many not be an expert in GSHP design – yet is assembled by another technician who may beg to differ with the designer. Adding insult to injury, part of the system has to be installed in the great outdoors.

With part of the system buried underground, troubleshooting the bore field turns into a mind field. Compare that to a furnace pulled out of a box that’s just plugged into the gas line, fed electricity, connected to ductwork and barring some major design oversight, the system functions at the plate efficiency. Not so for GSHPs. It isn’t uncommon for new cottage owners to either put up with cold winters or be saddled with incredibly huge electricity bills during winter months and what if electricity prices go up?

Solution: Computer Energy Simulation for Optimised Building Shell

So is there a better way? Yes, invest in energy modeling early in the design phase. Often the designer, architect or builder will have to go through this process anyhow to pull a permit if you have more than 22% window to wall ratio and if you hire a company like BlueGreen Group which specialises in building shell optimization for efficiency, we can help you out of this trap often with imperceptibly small tweaks to the design.We can help lower the heating demand to the point where a GSHP can be either significantly reduced in size (less expensive bore field drilling!) or where alternative heating systems become more practical.

If you get the heating load low enough through good envelope design and attentive assembly, you may be able us use an Air Source Heat Pump (ASHP) which, much like a furnace, is pulled out of a box and its installed efficiency is close to its plate efficiency. In the last number of years the Asian manufacturers have made huge leaps in efficiency gains to the point where an ASHP runs more efficiently than a GSHP and is only 30% the installed cost of a GSHP.

As for the fireplace, Rumford style fireplaces should be avoided especially on outside walls because the massive masonry chimney can’t be insulated and getting a draft gong on a cold day is difficult. Best to situated it in the house where the chimney is kept warm, but to also consider installing an air tight stove or masonry heater which have all of the plus sides of a traditional fireplace and very few downsides. Besides who wants to spend time splitting and schlepping wood, we just want heat and fire!

Other tips include, buying land that sits to the north of the lake so you can have your cake  – large south facing windows for maximum view and winter solar heat gain – and eat it too. Next, consider installing Photo Voltaic electrical generating panels on your roof, that way if you opt for a the smaller ASHP, you can use the electricity generated on your roof. You can also use the roof top power generated to heat your water with a new air source heat pump water tank too.