1900 sq ft home in canada

[helloprick]

Hi,
Can someone answer my question. I live in Toronto and have a 1900 sq ft home with a walk out basemend and east/west exposure. My builder say my load calc is 2.1 with a walkout.
Do I purchase a 2 ton or a 2.5 ton * Or does it matter.

Thanks,

HP.

[nomadpeo]

maybe get an independent contractor to do a manual j and compare results.

[helloprick]

that's a great idea.
i've had 5 different contractors come in and none have even mentioned a manual j. They just pull out their table and say "a house this size needs 2.0 ton or 2.5 ton".

is there much of a difference between the 2 *

Thanks,

[nomadpeo]

6000 btu's (lol)

actually, square footage is only one of the factors. the manual j will take into consideration heat gain due to leaks, insulation, construction materials, windows, etc. in some cases, it's possible to use experience and rules of thumb to determine tonnage, but if there is a question, it should be calculated by someone who has the proper tools and expertise. also, the seer rating and system configuration proposed will have some bearing on the tonnage selection. for example, a 2 stage compressor with variable speed blower and humidity control will be more efficient. if it's efficiency you are concerned about, seal the house well and add extra insulation, then spend money up front on equipment for long term savings.