Heating and Heat Distribution

While they still have their place in the market, mid-efficient furnaces are generally not installed in R-2000 Homes. Because they vent their combustion products up a B vent chimney, they are subject to backdrafting under negative house pressures. Negative pressures are more regularly encountered in airtight R-2000 Homes when any exhaust device such as a kitchen range hood or clothes dryer is operated.

High-efficiency condensing furnaces are an excellent choice for a new R-2000 or conventional house. Their higher combustion efficiency saves money and the sealed combustion process protects you and your family from potential backdrafting of combustion products in to the house, even under large internal negative air pressures.

High-efficiency condensing furnaces with two stage burners and energy efficient blower motors are more costly but are worth serious consideration. The two stage burners offer a comfort advantage, as the furnace runs longer and promotes more even temperatures. The HRV system in an R-2000 Home is interconnected with the furnace fan to distribute the fresh air to all areas of the house. A furnace fan run on continuous low speed consumes much more electrical energy. The significant dollar savings offered by the low energy use blower motor can easily cover off the upcharge cost. In addition, these motors have the ability to be operated at much lower, more desirable airflow speeds than standard furnace blower motors.

What size of furnace: The more energy efficient the home, the smaller the heating system should be. A HOT2000 computer heat loss calculation will identify the correct size of furnace for your home.

Install a furnace that is too big for the house and it will tend to come on with a big block of heat for a short time period and shut off for a longer period before coming on again. This will lead to temperature swings in the house and a loss of efficiency. A correctly sized furnace, which matches the heat loss of the building envelope, will run longer at a lower heat and improve comfort and energy efficiency.

Duct distribution design

You can select the best furnace on the market and size it appropriately, but if you can't get the proper amount of heat from that furnace to the far upstairs bedroom, no one is going to be happy!

Ductwork sizing and layout design needs to be done by an industry professional who has taken the appropriate HRAI training. For the last 20 - 30 years, houses have tended to follow a more standardized, simple design. As the industry built thousands of similar 1,200 - 1,500 sq. ft. bungalows, duct design evolved to more "rules of thumb" of what worked. Very little, if any, actual design calculation was really needed, or was done. Over the last 10 years, house designs have gotten more complex with larger windows, higher ceilings, more exposed floors and bigger spaces that simply will not work based on the same rules of thumb.

Heating and ductwork distribution system design is currently not done on many new homes in Manitoba as most homeowners do not realize the value or are not willing to pay for it.

A trained professional should be paid to do a room by room heat loss calculation and full ductwork design on new homes of any non-standard design complexity. A couple of hundred dollars in design fees will more than pay off in an end product that meets or exceeds all homeowner expectations. The correct sized ducts will be chosen based on the volumes of air required. A proper return air system will be designed to allow air to return from each room of the house. Ducts will be laid out as smooth as possible with elbows and transitions minimized - all forming the necessary foundation of a proper heat distribution system.