Many different expenses should be taken into account when determining how large a house you can afford to purchase. A number of ongoing expenses are related to the amount of square footage, including heating/cooling, maintenance, electricity, and taxes. Some of these costs are relatively minor, while others can be difficult to afford.

Heating and cooling expenses rise as the square footage of a house is larger. You should determine what the cost of heating fuel and/or electricity is in your area and make an attempt at determining how much this would cost, perhaps using the amount of square feet and heating/cooling expenses of your current residence to help calculate this. This expense will also vary depending upon the amount of insulation, height of the ceiling, and number of windows. Depending upon the plumbing, type of cooling/heating systems, and layout of the house, it may be possible to only cool or heat some rooms during the summer and winter, temporarily not using the others. It is more difficult to do this in a house which has a small amount of large rooms rather than many smaller rooms.

Large homes usually have a greater monetary value; this is used in determining the amount of property taxes and some insurance rates, causing them to be harder to afford. The expense of maintenance, such as painting or roofing, is also increased by the larger size of a house. Owning a large home can indirectly increase costs in some ways as well; it is easier to make more purchases (furniture, appliances, electronics, etc) if there is much extra space to put them in. The cost of cleaning a larger house (electricity, vacuum bags, glass cleaner, etc) is more expensive as well. Installing new systems in a large home will also be more costly, including new security, heating, central vacuum, or fire alarm systems. The same applies to upgrading or replacing systems which have failed or become antiquated. An expansive house is likely to come with larger appliances (refrigerator, freezer, oven) which consume a greater amount of electricity when operating.

Determining how much it will cost to live in a house and making sure it is less than your income (preferably allowing you to afford a temporary loss or reduction in income) is an important step which should always be completed before purchasing a new residence. If a large house is in need of particular types of maintenance or lacks necessary systems, this will also be a major expense you must afford.