Calendar icon February 6, 2023

Air Filter Sizes & How They Work

What is an undercut? What does nominal mean? All the answers are right here.

 

One of the more needlessly confusing elements of home wellness is air filter sizing. We didn't make it this way, but we are making it is as simple as possible for you right here. Let's get started.

The two types

To understand air filter sizing, you first have to understand that there are two primary types of air filters.

  • 1-inch and 2-inch air filters
  • Whole house air filters

Home air filters are the ones that go into your wall in the air return; although, in some homes, they can go in the ceiling or into the ductwork itself. Your "air return" is aptly named—it's where "air returns" to your HVAC system from inside your home. Most filters for your return are 1" thick. While 2" filters are found in some homes, it's a lot less often.

Whole house filters usually go into an air handler, which is typically situated next to your HVAC system itself. In some homes, these go directly into the ductwork too. It's worth noting that, while you usually only have one, it's possible to need more than one whole house filter for your home. Whole house filters always have a thickness of 4, 5, or 6 inches.

You may have noticed that we did not mention 3-inch filters. While 3" filters technically do exist, they're particularly rare. If you need a 3" filter, you are special.

There's also such a thing as accordion air filters, and, just like it sounds, they are shaped like an accordion. If you have one of these in your home, we sell those too, but...well, that's just weird.

Air Filter Sizes: Length and width

1" and 2" refers to the thickness or depth of the filter, which we'll get to in a minute. First, let's talk about length and width. Length and width are technically interchangeable, but for discussion purposes, a 12x20 is 12 inches long and 20 inches wide. It's a very common size that is easy to find, and it's on a short list of sizes that are common enough for air filter companies like us to keep in stock. Some other common sizes are:

If you have a 1" or 2" air filter that is not on this list, you'll likely need a custom cut, and the hardware store definitely can't help you here. We've got you covered, though. With our custom air filters, there are 66,000 possible different sizes. We know! That's a lot.

To put 66,000 in perspective, that's roughly the population density of Manhattan per sq mi. That's also approximately how many Orangutans are alive today. Take those facts to trivia.

Undercuts and roundings

A 20x20x1 air filter is actually 19-¾" x 19-¾" x ¾". This is what is known as the undercut. All 1" and 2" filters are undercut by a quarter of an inch to provide a little bit of leeway to ensure it fits into the air return without being too big. This includes custom sizes, so a 27-⅜" x 23-⅝" x 2" (which is the weirdest size we could think of) is actually 27-⅛" x 23-⅜" x 1-¾".

At SecondNature.com, you'll see an actual size that shows the undercut when you enter a custom size. You'll want the custom size you pick to be the size of your return measurements, which allows the actual size to be a quarter-inch less.

Undercuts exist on whole house filters as well, but not in the same way they do for 1" and 2" filters. In fact, undercut is a bit of a misnomer when it comes to whole house air filters. These are actually just rounded to whole numbers in a somewhat arbitrary fashion. Allow us to explain.

Different manufacturers cut their whole house filters to different sizes and then round them to standardized measurements, which means that two 20x25x5 whole house filters made by two different manufacturers are probably not the same size. Below are some examples:

  • Honeywell has a 20x25x5 is actually 19-3/4" x 19-7/8" x 4 3/8"
  • Filtrete has a 20x25x5 is actually 19.75" x 24.4375" x 4.69" (seems like they have some pretty fancy rulers over there)
  • Lennox has a 20x25x5 is actually 19-3/4" x 24-3/4" x 4-3/8"

And that all makes total sense...?

Because of this, it's necessary for those of you that need a whole house filter to know the exact filter size you need. If you can't find that on the filter, you can provide Second Nature with the nominal size and the brand that you had previously been using, and we'll be able to find the filter you're looking for.

Nominal vs. Actual size

All filters are sized two different ways. Yep, you read that correctly. All filters have an actual size and then a nominal size. The actual size is the exact dimensions with no rounding; whereas, the nominal size is the rounded dimensions of the filter. This means that on 1" and 2" air filters, the nominal size does not include the undercut, and the actual size does include the undercut. On whole house filters, the nominal size is the rounded size, and the actual size is just the unrounded. Pretty easy stuff here.

Sizes can be reversible

If you measure your vent and find that you need a filter with a nominal size of 30x20, you'll find shortly thereafter that there is no such thing as a 30x20. There is only a 20x30, and that is what you actually need. Whether the pleats on the filter run horizontally or vertically won't impact the effectiveness of your filter, so the number of unique air filter sizes on the market can simply be cut in half by always listing the smaller measurement first instead of having a 20x30 and a 30x20 as two completely different products. If you find that you need a 15x34, grab yourself a 34x15 and just rotate it 90 degrees. It's the same thing.

And that's how air filter sizes work. It's probably a little more complicated than it needed to be, but we try to make it easy. Now you'll never be confused by things like undercuts again.

tl;dr: air filters have weird sizes. Leave the rest to us—we'll make sure the right ones get to you right when you need them.

‍refrigerator water filter reduces.

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10 Best Property Management Websites for Property Managers

One important approach that property managers can take to keep up to date with current industry trends and approaches is to maintain a watchlist of different property management websites. That's because these sites often reflect best design practices and website templates as well as content sharing ideas. Today we'll cover some of the top property management websites, all considered favorites and regularly featured on “Top 10” lists in the industry, with a focus on what makes each one distinctive, whether from a design optic or a content perspective. 1. Second Nature It may seem odd for us to mention ourselves first on this list, but we are genuinely proud of our brand and messaging! After all, we’re in this business for a reason – and that’s why the content of the Second Nature website is so squarely people-focused, with an emphasis on solutions that improve the lives of residents, investors, and property managers alike. There’s a robust business principle underpinning this “Triple Win” philosophy: residents want their needs proactively anticipated, and they're willing to pay (and stay) for that service. This is particularly true for a younger generation that is attuned to the convenience offered by services such as Uber and Amazon. That’s why the language used on the website reflects a humanistic approach that goes beyond transactional basics, preferring “residents” rather than “renters,” for example, or “home” rather than “rental property.” It’s also why Second Nature’s “Resident Benefits Package” is front and center, and designed to give residents, investors, and property management businesses a win. Accordingly, like all successful marketing, Second Nature’s value proposition is not only tangible – it’s personal. Visit www.secondnature.com to learn more. 2. Nest DC The Nest DC website also focuses on the families behind the doors and the people behind the investment portfolios. Although residential real estate management is associated with a certain gravitas, the language as well as the overall branding of the Nest DC website plays off of a certain “avian” riff and is designed for easy readability. Where most sites incorporate an “About Us” page, for instance, Nest DC features an “About the Birds” content piece. It’s all done with serious intent, however, and the website design is sleek, clear, and user-friendly. Visit www.nest-dc.com. 3. Bay Management Group As soon as you hit the homepage of the Bay Management Group website, it’s clear that its primary target audience consists of real estate investors and property owners. That said, the site does host an impressive library of instructional and advisory videos for tenants, property managers, and landlords, as well as investors. With the tagline “property management that’s a cut above the rest,” home page testimonials, and a blue-toned web design of the sort favored by financial institutions to connote trustworthiness, the focus is on differentiation through delivery of high-quality property management services to deliver reliable rental income. Beyond its primary “free property management analysis” feature, other web functionalities include a blog, owner portal, tenant portal, and various program application options. Visit www.baymgmtgroup.com 4. Rentberry Rentberry is a global rental platform describing itself as a “transparent and secure home rental platform that connects tenants and landlords.” With the tagline “Renting done right – finally,” its principal focus is on prospective tenants and landlords. Top-level navigation includes online rent payments/rent collection. It also includes tenant screening functionality as well as options to search listings for vacancies or create a property listing. Among the usual resources (blog, help center, FAQ, contact information), Rentberry also features pricing guides for both tenants and landlords to help streamline the onboarding process. Visit www.rentberry.com 5. Grace Property Management & Real Estate Based in Denver (Colorado), Grace Property Management & Real Estate focuses on both residential and commercial properties in Denver. Although the company was founded in 1978, its online presence boasts astute use of online marketing tools and property management solutions, to say nothing of search engine optimization, with numerous calculators and other resources available from the top-level menu. Like many companies with a strictly regional presence, Grace Property follows the tendency of including full social media and phone contact information in the header. Visit www.rentgrace.com. 6. MESA Properties MESA Properties gives its geographical focus the hero image treatment, with the tagline “Servicing the Inland Empire, Eastern San Gabriel Valley and High Desert.” Below the header, it also bills itself as “an owner-centered property management company.” Accordingly, much of the functionality on offer from the top-level navigation is focused on professional property manager services and resources for owners, but it does include resources for tenants, including maintenance request options, and portal login. Visit https://www.mesaproperties.net/ 7. Golden State Property Management The Golden State Property Management website presents with the tagline “Total property management of the most comfortable homes in the South Bay,” as well as two prominent feature buttons aimed at residents (“Pay Rent”) and potential residents (“Search Vacancies”). With straightforward top-level menu options, mobile-friendly design, and high-contrast navigation elements, this site is exemplary in its simplicity. Visit www.goldenstatepropertymanagement.com 8. Sleep Sound Property Management Sleep Sound Property Management takes aim at the stress of managing the rental process, and as such takes on an advisory persona in its content. With the word “guarantee” appearing over 10 times on the homepage alone, the message is clear: this is a company devoted to providing great property management services in support of maximizing investment returns. Its “Why Choose Us” page also highlights its investments in cloud-based property management software, also designed to ease the stress of managing property investments. Visit www.propertymanagementportlandor.com 9. Good Life Property Management The website of this San Diego-based property management company is one of the only companies in the industry to highlight customizable user elements (color and font size) in the header of every page of its website. From the marketing perspective, this sends an important signal that the company is serious about finding ways to partner effectively with its community of investors and tenants. Visit www.goodlifemgmt.com 10. Luxury Property Care Luxury Property Care bills itself as “Florida’s only full-service property management and investment concierge for residential and commercial properties.” Its focus on offering high-end services is reflected in its mission statement: “Treat yourself to the luxury you deserve and let us handle every aspect of investing in off-market real estate and building a first-class rental empire with ease.” It’s also reflected in the website design scheme, with black and gold color elements being a popular way for brands to convey notions of elegance and prestige. Visit www.luxurypropertycare.com Follow the Second Nature Website to Keep Tabs on the Property Management Industry At SecondNature.com, you’ll find an abundance of resources designed to keep you up to date on events, analysis, and expert perspectives in the field – all geared toward helping property managers create a “Triple Win” that benefits residents, investors, and property managers alike: Triple Win Property Management Blog Triple Win Property Management Podcast Triple Win Property Management Events Learn more about Second Nature’s Resident Benefits Package, which is designed to generate revenue and establish Triple Win conditions for your residents, investors, and business.

Calendar icon February 26, 2024

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10 Best Property Management Blogs to Read and Learn From

As a property manager, one of the best ways to stay attuned to the latest trends, technologies, and strategies in the field is to read industry blogs across a range of property management websites. That's because the content of these blogs often consists of shared best practices and practical tips from peers and other experts. They also help you keep abreast of any regulatory changes and compliance requirements that may inform your business decisions and strategies. Today we'll cover some of the top property management blogs, with a focus on what each site brings to the table. 1. Second Nature The SecondNature blog provides insights on a wide range of topics related to property management, including market trends, technology, resident retention, and more. Its focus is primarily on a “Triple Win” philosophy, which expresses the idea that residents, property managers, and investors can go beyond transactional basics to create new, mutually winning experiences. In that vein, sample blog post titles include “How to Start a Resident-focused Property Management Company in 13 Steps,” “9 Ways to Improve Your Resident Experience,” and “How to Craft a Lease Renewal Letter that Wows Your Residents.” With top categories ranging from “Operational Efficiency” to “Resident Experience” and “Homeowner Insights,” the SecondNature blog is a valuable, highly readable resource for property owners and managers alike. Visit the SecondNature blog 2. Bay Management Group Blog The Bay Management Group manages over 6,000 units throughout Pennsylvania, Maryland, Northern Virginia and Washington, D.C. Its blog reflects this partially regional focus, with categories including “Owning a rental property in Maryland,” “Owning a rental property in Pennsylvania,” and the like. However, much of the content is broadly relevant to the property management business, with articles including “7 Ways to Ensure Your Potential Tenant’s References are Real,” “Tips for Successful Real Estate Partnerships” and “What is the Renter’s Bill of Rights and How Does It Protect Tenants?” This is a great blog that hosts archives going back to July 2012, making it one of the more venerable sites in this list. Visit the Bay Management Group Blog 3. Nest DC Blog Nest is a Washington management firm that focuses on homes and residents in and around Maryland, with expertise in single family homes, condos, multifamily housing, and mixed-use property in high-density, urban environments. Its clean, stripped-down design dispenses with the standard trappings of blogs such as tags and categories, and features both job listings and articles, with sample titles including “Important Factors for Real Estate Investing,” “Best Practices for Tenant Screening,” and “A Guide to the Eviction Process in Washington DC.” Visit the Nest DC Blog 4. Buildium Blog The property management software company Buildium publishes blog posts and other resources on a wide range of property management topics, from accounting & taxes to legal considerations, to marketing tips and the latest news from Buildium. Clearly, the content is aimed at a broad segment of the property management community, including rental property owners, property maintenance professionals, and real estate investors. Sample blog post titles include “The ins and outs of HOA reserve fund accounting,” “The best rent payment app in 2024: Comparing 8 online rent payment systems,” and “The 5 best multifamily property management software solutions in 2024.” Visit the Buildium Blog 5. Appfolio Blog Another software company, Santa Barbara (California)-based AppFolio focuses on SaaS for the real estate market. You do not need to be a user of the Appfolio software to find its blog relevant – in fact, much of the content focuses on issues of broad interest to property management and property investment groups, with sample blog article titles including “Three Leasing KPIs Every Property Manager Should Track to Optimize Their Business,” “4 Ways to Strengthen Vendor Relationships,” and “Your Ultimate Guide to Leasing Season: How to Maximize Occupancy and Efficiency.” Visit the Appfolio Blog 6. BiggerPockets BiggerPockets is positioned as a complete resource for anyone looking to succeed in real estate investing. Thus, its blog is squarely focused on matters relating to property investment and rental income, with titles that reflect that focus (e.g., “12 Ways To Make Passive Income From Real Estate Investing,” “High Credit Borrowers Get Punished and New Landlord Laws Put Tenants First,” and “2024 Rental Market Outlook: Is a Shift Coming Next Year?”) However, it also provides a number of articles with potentially broader interest to property management services (e.g., “Put THIS in Your Lease Agreement (So Tenants Don’t Break It!)” “9 Ways Your Property Management Tool Can Improve Your Business,” and “The Rise and Fall of the American Shopping Mall”). Visit the BiggerPockets blog 7. Rentometer Blog Rentometer provides a number of offerings around its collection and analysis of approximately 10 million rental records annually. The Rentometer blog is an extension of this capability, and aims to provide marketing insights to help manage real estate businesses. Its blog publications date back to 2018, and provide perspectives on remote property management, tools for growing real estate businesses, and more. Sample titles include “6 Tips for Communicating Rent Increases,” and “How to Use Rent Comps When Setting Your Rent Price.” Visit the Rentometer Blog 8. Propertyware Blog Like Buildium, Propertyware is an acquisition of the RealPage corporation but it continues to maintain a blog featuring news, trends and tips on single-family rental properties. Sample titles include “10 Tips For Maintaining Electrical Safety At Your Rental Homes,” “What’s Hot: Tankless Water Heaters for Rental Housing,” and “How Rental Property Software Helps in Processing Security Deposits.” The blog has also compiled different article series under various themes and topics, making it easier to navigate the wealth of information on offer. Visit the Propertyware blog 9. Rent Manager Blog The Rent Manager blog is largely focused on news about this property management software developed by London Computer Systems (LCS), and features tips and best practices for users, as well as news on feature enhancements. However, the blog also includes a dedicated category for property management trends, with articles such as “The Benefits of AI for Residential Property Management,” “Why Lowering Renewal Rents is a Smart Move for Multifamily in 2024,” and “Resident Screening: The Lost Art of the Reference Check.” Visit the Rent Manager blog 10. All Property Management Blog The All Property Management Blog reflects its identity as a marketplace of property management services, with articles aimed at real estate investors as well as property managers. Blog categories include property management tips and advice, product reviews, and content related to property taxes and finances. Sample titles include “How to Rent Out an Apartment: The Go-To Guide for New Landlords,” “Top 10 Rental Listing Syndication Websites and Time-Saving Tips,” and “5 Successful Rental Property Management Strategies.” Visit the All Property Management Blog Follow the Second Nature Blog, Podcast, and Events to Keep Tabs on the Property Management Industry At SecondNature.com, you’ll find an abundance of resources designed to keep you up to date on events, analysis, and expert perspectives in the field – all geared toward helping property managers create a “Triple Win” that benefits residents, investors, and property managers alike: Triple Win Property Management Blog Triple Win Property Management Podcast Triple Win Property Management Events Learn more about SecondNature’s Resident Benefits Package, which is designed to generate revenue and establish Triple Win conditions for your residents, investors, and business.

Calendar icon February 21, 2024

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