1. In newer subdivisions, dates can be obtained from manhole covers, sidewalks, and curbs.
2. Double-glazed windows usually have the manufacturer's name, a CMHC number, and the date of manufacture.
3. On houses built within the last 20-25 years, you will often find a sticker on the outside of the electrical panel, indicating the possession date of the house. The Ontario New Home Warranty Program (in its earlier days, known as HUDAC) placed these stickers on the elctrical panel so that the warranty period could be established easily.
4. From the 70's and 80's , a sticker can be found on the plumbing stack, indicating the date of the final plumbing inspection.
5. If you can be sure that teh furnace or the water heater is original, the gas inspection sticker on either of these applilances is a good indication of the age of the house. Typically, a green sticker ranges from the late 1950's to 1970's. Blue is 1980's and black is used thereafter. Also, you can identify the age of the furnace by removing the blower door compartment to locate the date stamp on the fan unit.
6. Porcelain plumbing fixtures usually have a manufacture date stamped into them. If you remove the lid from the toilet tank, the date will often be stamped on both the underside of the lid and inside the tank.
7. Houses with copper plumbing stacks were built between 1959 and 1968.
8. Aluminum wiring was used residentally between 1969 and 1976.
9. Knob-and-tube wiring, galvanized steel plumbing and lead incoming lines are pre 1940's.
10. The simplest method...Ask your Realtor and your lawyer who can check with municipal offices and government agencies to ascertain this information.