Choosing a suitable HVAC unit for your home can be a daunting task considering it’s a big and long-term investment. One of the most important variables to consider when purchasing a new cooling and heating unit is its size. Unfortunately, many people think that the bigger the equipment, the greater the value it offers. When it comes to an HVAC unit, a bigger system isn’t always better, nor does one size fit all. An undersized HVAC will need to work harder and run longer to cool or heat your space. On the other hand, an oversized system will cool and warm your house faster, but you might end up with hot and cold spots in your home. If you are shopping around for a new HVAC unit, the factors below will help you select the ideal size for your home.

1. Square Footage

The first step you need to take when determining the size of the HVAC unit to purchase is calculating the square footage of the area you intend to heat and cool. If your home has rectangular or square-shaped rooms, you can get the square footage by multiplying the width and length. However, if you’ve got a multidimensional house, start by dividing it into different sections and calculate the square footage of every section separately. You can calculate a triangular room’s square footage by multiplying the width by length and dividing the outcome by two. For circular rooms, determine the distance from one end of the space to the center to know the radius. Calculate the area of the room and get the sum of all rooms.

When calculating your home’s square footage, remember to exclude any spaces in the residential property that you don’t intend to cool or heat. Such areas may include corridors and sunrooms. Also, if you’ve got some rooms that cut through to each other, treat them as single rooms. For instance, if you have an open kitchen without a door separating it and the sitting area, treat both areas as a single space. Add the separate square footage to get your home’s square footage.

2. British Thermal Units

Generally, BTU is used as a universal unit of measurement that indicates the cooling capacity of an air conditioning unit. To determine the BTUs needed to cool your residence, multiply the square footage you calculated earlier by 20. You require 20 BTUs to adequately cool one square foot as a general rule of the thumb. For instance, if you have a rectangular room that is 40 feet wide and 30 feet long, its square footage will be 45 x 30 = 1,350. To determine the minimum cooling capacity required, multiply the answer by 20, and in our case, you will get 27,000 BTUs. The cooling capacity of an air conditioner can either be in tons, wattage, or BTUs. One AC ton is equivalent to 3,500 watts of cooling, which is equal to 1,200 BTUs per hour.

3. Insulation Level

The level of insulation plays a vital role when determining the correct HVAC size for your home. A properly insulated home prevents heated or conditioned air from escaping outdoors and needs a less powerful HVAC. However, if there are gaps or openings in the ceiling, doors, attic, or windows, you’ll need an HVAC with a bigger capacity to keep your home comfortably warm in winter and cool during the summer season.

Before purchasing and installing an HVAC unit, consider addressing air leaks in your home. Also, ensure that there’s adequate insulation in the walls and attic. Weatherstripping your doors and windows will hold cooled and heated air inside the house, allowing your cooling and heating unit to operate more efficiently.

Currently, many states have some building codes that indicate the minimum levels of insulation allowed for residential and commercial buildings. That means modern homes have better insulation than their older counterparts. If you live in an old house, you might need an HVAC unit with a bigger capacity to keep your home comfortable all year.

4. Quality and Size of Ductwork

Leaky, damaged, or poorly installed air ducts can allow conditioned air to escape. As a result, your HVAC will need more cooling power to maintain the desired indoor conditions. Therefore, you should contact a professional to check the status of your air ducts before purchasing your cooling and heating equipment. These experts can seal the leaks or recommend a new ductwork installation to help deliver the right air volume in your house at the required temperature. The professional can also help you match the size of the ductwork with a suitable HVAC system.

5. Type of Windows

Many people love big windows because they give stunning views, allow enough lighting, and create an illusion of a bigger space. However, these windows can have a negative effect on your home’s temperature. Generally, windows allow heat entry, increasing the total air volume that an air conditioner needs to cool in your home. If your rooms have more than one big window, you need to add 10% BTUs to the calculated amount for every extra window. However, if your windows are well-insulated and you keep your blinds, shutters, and curtains closed most of the time, they can help keep the summer heat out. This way, you can cut your cooling capacity by approximately 10%.

6. Direction and Orientation of Your Home

You also need to consider the direction your home faces and its orientation. If your home gets a lot of sunlight, you may need more air conditioning to compensate for the heat gain during the summer season. The benefit in this instance is that you are likely to need minimal heating to keep your home cozy and warm in winter.

7. Number of People in Your Household

Generally, every human body dispels some amount of heat. Typical BTU estimates work on the assumption that each room in your home has two people. If you have more than two people occupying a space simultaneously, you need to add 600 BTUs per person per hour. Also, if you’ve got an indoor gym, add approximately 380 BTUs for each person using the gym at a particular time. That’s because the workout activities will increase the amount of heat dissipated in the room.

8. Your Home’s Climatic Region

A home in a mildly hot region will have different cooling needs from one in a hot and humid area. If you live in a region with a hotter climate, your HVAC will need to work harder to attain and maintain the desired indoor conditions. Consider adding 10% to 20% BTUs for each room to keep your home comfortable.

Contact the Cooling and Heating Experts

You need to know the square footage of your living space and the required BTUs to guide you in purchasing the correct HVAC size. A properly sized cooling and heating unit will maintain healthy humidity levels, leaving the house comfortable all year round. It will also run efficiently, reducing operational costs in the long run. If you need help determining the right HVAC size for your residential property, reach out to Environmental Heating & Air Solutions. We specialize in heating and cooling installations, maintenance, and repairs. Our company also offers plumbing and air quality services throughout Roseville, CA and the surrounding area. Call our friendly representatives today to book your appointment.

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