Posted on January 15, 2021
The HVAC duct sizing rule of thumb will help ensure the home’s HVAC system keeps up with weather demands. The size of the HVAC unit alone doesn’t tell you how efficiently it will work, as several other factors play a role.
One important aspect is the size of the ductwork. If you are trying to determine which size is best, don’t worry - we’ve compiled some information to help.
HVAC stands for heating, ventilation, and air conditioning. The air ducts are the part of the system that channels air through a structure.
Essentially, the HVAC unit fills the supply plenum with air that’s either heated or cooled, as specified by the thermostat. A plenum is an air-distribution box attached directly to the supply outlet of the HVAC equipment. When the fresh air enters a room, it pushes the stale air that’s already present into another set of ducts. The stale air travels through the ducts until it reaches the return plenum.
The ducts have to be the correct size for the AC unit to work correctly. When ducts are too small, the HVAC unit must work harder to keep the home at the predetermined temperature. Alternatively, if the ducts are too large, it compromises the velocity of the air. This means you won’t have proper air flowing through the vents.
To calculate the duct size, you first need to know the size of the HVAC unit you need or have. You likely don’t know that off the top of your head. So, this is where the rule of thumb comes into play.
The rule of thumb is: you need one-ton of capacity for every 500 square feet of floor space. So, if you have a 2,000 square foot house, you need or likely have a 4-ton unit.
Unfortunately, the HVAC duct sizing rule of thumb ends there. At this point, you need to use a rather complicated equation to calculate duct size.
There are a few other things you need to know to calculate the formula effectively. Here are all components:
1. Determine the home’s square footage.
2. What size AC unit is it? (calculated using HVAC duct sizing rule of thumb)
3. Determine airflow velocity.
4. Account for friction loss.
5. The static pressure of the AC unit.
After you’ve collected this information, here’s what you do:
1. Check the unit to determine how many BTUs are produced. You can usually find this information on the unit plate. Divide the number of BTUs by 10,000.
2. Multiply the number from step #1 by the Cubic Feet per Minute airflow of the unit. Ordinarily, natural draft units produce 100 CFM, an induced unit produces 130 CFM, and condensing units produce 150 CFM.
3. Divide the number from step #2 by 10. This answer will provide you with the airflow permitted by the home’s HVAC unit.
4. Now you’ll want to calculate the duct size. Do so by multiplying the length and the width. For example, if the home’s vents measure 4 by 8 inches, the total CFM is 4x8=32.
5. Take the CFM per vent and divide it by the total amount of CFM for the unit.
6. Next, calculate the square footage of each room in the home. This number is found by multiplying the room’s length by the width.
7. The last step is to divide the number of vents by each room’s total square footage.
This calculation can be confusing if you’ve never manually calculated it before. If you’re unsure, you can find duct sizing calculators online that will figure the formula for you, as long as you have all the required information.Or, of course, there are also professional tools and calculators to give a proper estimate.
MacArthur Co offers a wide array of HVAC products, including sheet and coil stock, ductliner, and all the necessary accessories for making HVAC ductwork. We partner with industry-leading manufacturers to bring you the best products on the market.
Posted on December 8, 2020
As an HVAC contractor, it’s crucial to stay up to date with any new regulations or guidelines being put out by agencies like the EPA. Because new information is continually being researched and analyzed, updated regulations are to be expected on a somewhat regular basis. Therefore, to make sure that your business stays compliant, you need to be checking for updates regularly. In 2020 the EPA provided new guidelines that affects anyone servicing HVAC systems.
While there has been a slow progression of phasing out HCFCs (hydrochlorofluorocarbons) since 2010, as of January 1, 2020 production and import of R22 refrigerant (also known by its brand name, Freon) is considered illegal in the United States. This is because it is considered an ozone-depleting substance (ODS). Research has shown Ozone depleting substances are responsible for destroying the ozone layer and creating an “ozone hole” over the South Pole. For more specific information, you can check EPA’s brochure on Phasing out HCFC Refrigerants to Protect the Ozone Layer.
HVAC units that were produced after 2010 shouldn’t be using R22 due to the limitations placed on production. These newer units likely use a more environmentally friendly refrigerant called R410A. However, any units that were made before 2010 will most likely use Freon. While it’s illegal to produce R22, it’s still legal to use units that use it and it’s likely that many of the units that you service still use Freon. But how does this directly affect your business?
Because of this ban on the production and import of R22, if you are servicing a system that relies on it, the only availability will be from recycled or stockpiled quantities. Due to supply and demand, it’s likely that R22 will continue to go up in price until it can no longer be found. Unfortunately, no one likes having to spend more than expected and you will have to explain this to clients when you are servicing older units that use R22.
The only other alternative will be to opt to invest in installing a new system which will likely cost them even more. The good side to this is that a newer system will likely be more efficient, and they will never have to have an R22 unit serviced again which may save them money in the long run as R22 supplies will continue to be more limited. This is a choice you’ll want to discuss with clients as their units that need R22 need service.
Summary of what you need to know:
● Production or import of R22 is now illegal in the United States
● The only way to source R22 will be through recovered, recycled, or reclaimed supplies
● Use and service of units that use R22 is still legal
● The price of R22 supplies will likely continue to rise due as it becomes more limited
● The phase out of R22 units should be mentioned to clients so they’re prepared to make informed decisions when it comes time to fix or replace a unit
Posted on October 23, 2020
As we watch the leaves change color and begin to drop to the ground, we are reminded that the winter months are ahead of us. In the same way we bundle ourselves up, our homes and businesses must also be properly bundled up with water and ice protection.
Let’s take this opportunity to look at just a few reasons roofing underlayment are an integral part of a roofing system.
Roofing underlayment are materials installed onto your roof’s deck that form a waterproof barrier. The underlayment acts as a base layer to your roof, as it’s placed under all other roofing materials. Its greatest benefit is that it provides protection from harsh weather for your home or business.
There are three main types of roofing underlayment:
● Rubberized asphalt
● Felt that’s saturated with asphalt
Roofing underlayment features a split release film that creates a watertight seal around penetrations caused by nails when the shingles are laid.
Even the smallest leak or buildup of moisture can cause significant damage. Moisture can cause mold and mildew, especially in attics where the temperature often fluctuates. Moisture can also affect the structural integrity of a building, with warping, rusting, rotting, and more. Suffice to say, blocking moisture is essential to not only the occupants’ health, but the health of the structure.
Water and ice protection is very important to protect your home from wind-driven rains. This is especially important for homes located in areas prone to hurricanes, tropical storms, or severe thunderstorms. The wind generated by such strong storms can cause rain to land under the shingles. When water and ice protective membranes are installed, it reduces the risk of this type of rain leaving you with a leaking roof.
It’s important to note that many national insurance programs don’t cover wind-driven rain when it comes to repairs. So, even though you have homeowner’s insurance, you may still be responsible for damages occurring from this type of water damage.
While hurricanes are a problem in the southern United States, ice dams are an equal concern in the northern regions that experience cold winters. Ice dams form following continuous freezing and melting of snow. This can be caused by the heat escaping your home or from gutters backing up once they’re full of frozen slush.
Essentially, the melted water flows beneath the snow and eventually freezes after it settles around unheated areas, such as eaves and soffits. This process causes damage because water is forced under the shingles and makes way into the attic. Thus, causing interior damages.
Shingles and other roofing provide some protection for your home’s interior, mainly deflecting the sun, blocking wind, and protecting against falling branches and such. While shingles help redirect water and certainly limit exposure to water, they can’t keep water and moisture entirely out.
As your roof ages, the shingles can become brittle after exposure to the sun and other weather patterns. So, when your shingles begin to fail, your underlayment is the last barrier that can prevent damages until you get a new roof installed.
In the end, water and ice barriers resist cracking, drying, and rotting, which provides long-term waterproofing performance. Hence, it has a low lifecycle cost. So, next time you are having a new roof installed, be sure to opt-in for quality roofing underlayment to give you the water and ice protection your home or building needs!
Posted on July 28, 2020
Wood has always been the go-to decking material, but composite decking is now giving wood a run for its money. Wood decks require a lot of maintenance, and some types of popular wood decking are not widely available. Composite decking, on the other hand, requires minimal maintenance and fits a range of budgets. Just as wood decking, there are pros and cons of composite decking, which we will explore in this article.
Unlike wood, composite decking does not need to be treated, painted, or stained. You’ll quickly find that if you don’t properly care for wood decking, it will fade, crack, weather, and split after it dries out over time.
As you can see, if you don’t put forth the effort to care for a wood deck, it will not look its best and even become a safety hazard. Alternatively, composite decks maintain a beautiful and consistent appearance for years to come. The only thing you need to do is occasional mild cleaning.
Composite decking is available in many colors and textures. You can even combine different colors to create multi-colored decks. If you like dramatic looks, consider combining dark and light tones. You will find most come in various shades of Earth tones such as gray, tan, and brown.
The other great thing is that if you live in a climate where you get a lot of rain or snow, composite decking can come with a non-slip texture. This is also perfect for those installing it near swimming pools or even in humid locations.
The manufacturing process used to make this decking helps the boards become impermeable to water. This feature also helps the material fight off mildew and mold better than real wood. Of course, there are still rules you should follow when installing it, but it’s easy to clean when mildew or mold does appear.
Wooden decks are put together using screws or nails that can create places of weaknesses on the boards. Not only will they require repairs at some point, but they can also be an eyesore if they’re not spaced properly. When you choose composite decking, it can be installed using hidden fasteners. It not only reduces the risk of weak places, but it also makes for a cleaner look.
Most people consider price the biggest con when it comes to composite decking. It can cost as much as 50% to 100% more than treated lumber. However, this number will vary depending on your location and what kind of wood you’re comparing it to. It’s also worth factoring in cost savings from not having to do regular, extensive maintenance.
If you live in a warmer climate, you may notice that the boards get hot. While you can choose a lighter color to help with this a little, it will still absorb at least some heat.
Composite decking features permanent colors to reduce maintenance. It is not designed to be painted or stained. It is possible to stain or paint a composite deck, but it requires a careful, labor intensive process.
If you decide composite decking is right for you, here are a few of the best brands you can buy:
In the end, composite decking is a great alternative to pressure-treated lumber. Not only is it aesthetically appealing, but it will last for many years to come! Best of all, it requires minimal maintenance so you can sit back and enjoy the outdoors.
Macarthur Co. is an employee-owned company that values quality products and services. For more construction tips and news, visit MacArthurco.com.
Posted on July 10, 2020
Each year in the US, hail causes significant damage and accounts for billions of dollars of insurance claims. When hail strikes, it not only damages your car and other personal property, but it takes a toll on your home as well - specifically your roof. Though these types of storms can be destructive, the amounts of damage vary greatly.
The following information will help you distinguish between hail damage and storm damage, discuss the signs of hail damage to your roof, and when you should call a contractor for repairs.
Storm damage can come in many forms but is most commonly caused by wind and hail. When you have wind damage, you are likely to notice that shingles on your roof are missing or torn.
On the other hand, hail can leave behind damage that’s harder to see with an untrained eye. This is especially true when smaller sized pieces cause the roof damage and there are no visible leaks. Yet, as with anything else, there are tell-tell signs to look for.
The roof damage you incur after a hailstorm will depend on what type of shingles you have. This is because hail damage will look different on composition and asphalt shingles than it looks on wood shingles. So, it’s important to know the differences in damages to each shingle type so you can properly tell if you actually have hail damage on your roof.
Here’s a breakdown of these damages:
● Damage that’s random and has no noticeable pattern
● Black marks from where the hail hit (known as a ‘scar’)
● The loss of granules which may expose the shingle mat portion of the shingle
● Mat and/or asphalt that seems shiny
● Places where hail hit that are soft to touch, such as a bruise on an apple
● Damage that’s random and has no noticeable pattern
● Splits in shingles that have an orange/brown appearance
● Splits in shingles that have sharp edges or corners
● Splits in shingles that have little or no deterioration near the edges
● Dents or other impact marks along the splits
● Gutters - Check for dents and dings on both downspouts and gutters. Another sign to watch for is gutters that are overflowing or clogged.
● Siding and Decks - Hail will also cause damage to other areas of your home. So, if you’re wary about checking your own roof you can check siding and decks for damage.
After a storm strikes, the first thing you should do is inspect your home. If you find any of the damages we discussed above, it’s a great idea to call a local licensed contractor. The truth is, hail damage gets worse over time. So, while the signs may not be obvious right away, the damage to your roof will continue to worsen, and eventually, it will begin to leak.
Always remember it’s better to make hail damage repairs as soon as possible. The longer you wait, the more money it will cost you in the long run!
MacArthur Co. is an employee-owned company that offers more construction tips and news on our news page.
Posted on June 19, 2020
Severe weather poses a risk to employee safety, as well as potentially disrupting or destroying construction progress. Although we cannot control the weather or predict it correctly every time, we can have a contingency plan in place. If a jobsite location is prone to severe weather, you must evaluate the site-specific risks and create an action plan accordingly.
Many forms of severe weather can affect the project and even be dangerous for the workers on the jobsite. Machinery on the jobsite can be damaged when snow or ice gets inside the heavy equipment and block the air flow, which leads to the freezing of the components. Freezing weather also affects diesel engines as the oil moves slower due to cold, and this increases the load on the machine. Winterizing the equipment is necessary to continue the work in the extreme cold.
Flooding, hurricanes and high winds are other forms of severe weather which can hit unexpectedly and can topple walls and equipment. You need to be prepared to relocate your heavy equipment quickly. Although extremely hot weather might not have much impact on the machinery or the different structures, it can pose a serious risk to workers. Heat illness and decreased productivity are common among those working in extreme heat, especially if they are also working with heavy equipment that puts off its own heat.
· Emergency supplies like braces, tie-downs, bottled water, flashlights, and first aid kits need to be fully stocked on the jobsite. Having a pump and other water/debris removal equipment at the site can be handy in case of floods. An emergency power generator system is also essential to avoid major delays in projects.
· Have an action plan in place, and review it with your employees at the beginning of every project. You should also revisit the plan at the beginning of every season to cover the main risks they might face in the coming months.
· Consider taking pictures of your jobsite at the end of each day, especially if bad weather is in the forecast. These photos can be used as proof of work completion to submit in an insurance investigation in case of damage.
· Store project documents in a safe or sealed container that cannot be easily damaged by fire, water, or extreme conditions.
· Prepare for quick relocation of expensive heavy equipment in areas prone to frequent hurricanes and severe weather.
· Designate a “safe house” or “safe area” on the jobsite for the workers in case of lightning storms, hurricanes, etc. As soon as workers hear thunder or notice heavy winds, they should stop all activities, remove all metal objects that are on them, and seek shelter in this area.
· After the storm, make sure designated employees assess damages, clean up the site, and determines if it is safe to resume the construction.
A storm preparedness plan can go a long way in mitigating the risks to employees and the project. Knowing what to do ahead of time can mean the difference between destruction and minor damage. Employees need to know what to do before they are under pressure to act. Preparing your jobsite for severe weather should be taken seriously.
MacArthur Co. provides quality building products to contractors, suppliers, and more. Established in 1913, we are an employee-owned company that prides ourselves on quality service that matches our quality products. With over 50 locations across the U.S., find a branch near you.
Posted on April 8, 2020
Distracted driving is dangerous under any circumstance. But distracted drivers in the construction industry pose an even greater risk because they are usually driving trucks, towing trailers, and hauling heavy loads. Construction businesses are trying to do their part to keep roadways safe by implementing distracted driving policies.
In this article, we will discuss the driving safety practices that the construction industry is working to enforce on an individual employee basis.
What Counts as Distracted Driving?
Many mistakenly think distracted driving is using a cell phone while driving, but that is not the case. Using a cell phone is a distraction, but only one of many. Drivers need to understand there are visual, manual, and cognitive distractions.
· Visual Distractions cause you to take your eyes off the road.
· Manual Distractions cause you to take your hands off the wheel.
· Cognitive Distractions cause you to take your mind off driving.
The most common visual, manual, and cognitive driving distractions are:
· Talking on a cell phone, even while using a hands-free device
· Using cell phone features, such as inputting GPS coordinates, checking email, etc.
· Adjusting dashboard controls, such as audio and climate controls
· Adjusting vehicle components, such as mirrors, seats, lighting, etc.
· Eating, drinking, and smoking
· Reaching for an item inside the vehicle
· Daydreaming or emotional distress
Texting is a triple threat, as it requires you to take your eyes, hands, and mind off the road. Talking on a cell phone is almost as dangerous as texting, even if using a hands-free device. According to NHTSA Traffic Safety Facts, texting and talking on the phone while driving accounts for 14% of all distracted driving fatalities.
How to Prevent Distracted Driving Disasters
The National Safety Council originally deemed April as Distracted Driving Awareness Month to promote the national #JustDrive campaign. In light of the coronavirus epidemic, NSC is postponing Distracted Driving Awareness Month to a to-be-announced date later in the year. However, the following safety tips should be practiced every day.
11 Safety tips to prevent distracted driving:
1. Remember your safety and the safety of others is most important. Remind yourself that It Can Wait until you are parked.
2. Activate your phone’s “Do Not Disturb While Driving” setting before you start driving.
3. Adjust your seat, the radio, and other components before you start driving.
4. Input GPS coordinates and review the route before you start driving.
5. Refrain from eating, drinking, or smoking while driving.
6. If stressed or upset, pull over to compose yourself before getting back on the road.
7. Never listen to music through headphones or earbuds while driving. Keep audio volume to a minimum.
8. Stay aware of your tools, trailer, and load at all times. Wrap a piece of tape around your steering wheel, or place another subtle reminder to check your load.
9. Never text or talk on the phone while driving. Remember, they are the most dangerous driving distractions even with hands-free devices.
10. Ask passengers to comply with your rules and company’s distracted driving policy. Ask them to buckle up, not distract you, and help you do any tasks that would otherwise distract you, such as navigating and adjusting dashboard controls.
11. Take the Just Drive Pledge.
From our work family to yours, MacArthur Co. wishes you safe travels!
Posted on March 20, 2020
Running a business is tricky on its own, and now we're all facing new challenges as we try to navigate through the pandemic. NRCA has provided a wealth of resources to help you through these uncharted waters. You can find them at https://www.nrca.net/covid-19-resources-for-roofing-contractors.
Posted on March 16, 2020
Thank you to SocietyInsurance.com for putting together this list - 6 Construction Job Site Safety Tips.
Visit their website for the full article.
Posted on March 11, 2020
Worker safety on the job site is always a priority, but sometimes it is hard to know what that looks like. The National Safety Council has compiled a list of 7 common workplace safety hazards they encounter when conducting safety audits. What kind of hazards do they see? Working at heights, chemicals, housekeeping, electrical, forklifts, lockout/tagout, and confined spaces. Because safety is everyone’s job, here are a few questions to ask yourself:
Go to the site below for the full article.
Posted on February 5, 2020
When working outside, Mother Nature can wreak havoc on our bodies. This week is Burn Awareness Week, so please take a moment and review these tips: Look closely at local forecasts; put on several layers of loose clothing; wear hats that completely cover the ears, warm boots, & mittens; drink plenty of warm fluids but avoid alcohol and caffeine; take frequent breaks indoors from the cold, especially when the temp nears or dips below -5. Click the link below for more tips and info.
Posted on August 6, 2019
From our Partners at Carlisle Construction Materials
Importance of Metal Roof Edges and their design, testing, and performance
· Metal Edging not only provides a sleek look but is critical to protecting the entire roof system
· Roof edge failure possibilities: Fasteners are uneven, the metal thickness is too light, and inside corners have no miters.
· The cost of perimeter edge metal is typically only 1% of the total building cost
· It carries the most risk for roof failure
· Solutions: ES-1 test standard developed by Single Ply Roofing Industry (SPRI) and ANSI
· Consideration of design are building height, location, local wind speed data, building occupancy factor, and special terrain characteristics,
· Several wind calculators can be found online at sites such as spri.org
· ANSI/SPRI ES-1 standard will help protect the complete roofing system
Posted on July 29, 2019
Recycled or reused material is being more of a standard in the world today. Johns Manville is following that and is finding new ways to use recycled material in their insulation. To learn more about how they are using recycled material follow this link (https://news.jm.com/blog/hvac-insulation/understanding-recycled-content-insulation-materials ). If you are interested in getting Johns Manville for your job, contact your local MacArthur Co. branch.
Posted on June 11, 2019
Your home is your number one asset. Why wouldn’t you want to upgrade the two most important aspects of it, your roofing and siding? Look at this article from DaVinci Roofscapes to see how upgrading your exterior will not only add curb appeal but can also save you money down the road. Check out the MacArthur Co. products page to find your upgrade.
#siding #exterior #roofing #DaVinciRoofscapes
Posted on June 6, 2019
Are you installing a new roof on your home? Check out this article from Atlas Roofing to avoid some of the most common installation mistakes: https://www.atlasroofing.com/news/article/shingle-installation-mistakes-that-cause-major-problems
Posted on March 7, 2019
Looking for ways to save time? Check out this new tool from CertainTeed Roofing, which helps contractors save money and improve efficiency. We've had numerous contractors utilize this tool and they say they can't imagine business without it anymore.