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free hvac tips advice size matters bay area


An efficient heating system needs to be appropriately sized. Unfortunately, most residential contractors don’t take the time to do a Manual J Heat Loss Calculation or a Manual D Duct Design Calculation to make sure that the system is designed correctly. Improperly-sized systems will mean years of discomfort and inefficient energy utilization. It is good to ask questions. Ask your contractor, or their heating subcontractor, to provide you with copies of their calculations, then find an outside heating contractor to evaluate and verify the data given.

free hvac tips advice size matters bay area


Bigger is not better when it comes to the sizing an air conditioner. A properly-sized air conditioner will operate more efficiently and will not subject occupants to extreme temperature changes between too cold and too warm. It is so easy to be sold an air conditioner with a larger capacity than is necessary, as we tend to equate “big” with “better”. In reality, a properly-sized air conditioner running over a more extended period will operate more efficiently, and will off more comfortable temperatures than one that turns on and off all the time. If you have an air conditioner that does this type of “short cycling”, then chances are it is oversized relative to your space.

free hvac tips advice size matters bay area


Your heating system is more than just your furnace. It includes the furnace, filtration, duct system, and the envelope of the house. No matter how efficient a furnace is, if the ducts in your home leaks, you are wasting energy.

free hvac tips advice size matters bay area


In older homes, air ducts were sealed with duct tape. Like most tapes, after a few years the adhesive wears out, and you no longer have a sealed duct system. To make matters worse, in some homes nothing but tape was used to seal the duct system. The ducts are the delivery system for conditioned air throughout your home. When we test duct systems, we typically find 30-50% leakage, meaning that only a portion of the heated or cooled air the homeowner pays for is being delivered to the home, and the rest is leaking out into the attic, walls, or crawlspace. Your ducts should be sealed professionally and then pressure tested to confirm that duct leakage is 6% or less than total system airflow. Many heating contractors do not have the training or experience to check and seal ducts; however, the leaders in the field do.

free hvac tips advice size matters bay area


Duct leakage is more than wasteful – it can also create pressure imbalances in your home. Leaky ductwork can draw pollutants into your home and can cause back drafting of indoor combustion appliances. To avoid these issues, your ducts need to be tested and sealed by a professional.

free hvac tips advice size matters bay area


During the construction process, a vast array of contaminants and objects were found in brand new ductwork in new homes, such as sawdust, soda cans, food bags, water, and other construction debris. To prevent further contamination, once the ducting is installed, it should be sealed to avoid the entry of all the things homeowners don’t want to be breathing for the next 30 years.

free hvac tips advice size matters bay area


Most filters were designed to protect the furnace from debris; they were not designed to protect our lungs from fine particulates. When looking at your filter, if you can see your hand through it, it was designed to protect your furnace, not to filter particulates to protect your lungs. Have your HVAC contractor install an easy-to-access, disposable, 4-6 inch, MERV 13 or better filter. Cutting edge, expensive, UV filtration equipment is not necessary in many cases. Ask questions – don’t just accept the default.

free hvac tips advice size matters bay area


Many homeowners experience excessive noise with some of their large appliances. Believe it or not, kitchen range hoods do not have to be noisy. You can now purchase remotely-located fans that can go in the attic and will be very quiet. As with many alternatives, if you don’t ask, you won’t be offered this option. For bathroom fans, Panasonic has a terrific line of quiet bathroom fans called “Whisper Quiet”.

free hvac tips advice size matters bay area


Pollutants, humidity, odors, and chemical compounds will accumulate in a home that isn't properly ventilated. Houses used to be so leaky that getting enough ventilation air was never a problem. Though you may hear contractors say a home can be “too tight", a better approach is to “seal it tight, then ventilate right". Rather than leaving ventilation to chance penetrations in a structure, all penetrations should be sealed tightly and the home should be pressure tested with a device called a blower door to confirm that proper ventilation rates are achieved.

free hvac tips advice size matters bay area


Insulation, done well, is perhaps the single most important, and least expensive upgrade we can make to make a home energy efficient. Unfortunately, often insulation is not done well. There is a myriad of choices and approaches, including fibreglass batts, dense-pack or loose-fill cellulose, and closed-cell foam insulation. Closed-cell foam insulation is expensive but ideal because it provides both a thermal barrier and an air barrier. Insulation is both an art and a science. The difference in price between a quality insulator and a low-ball firm is minimal when you consider the impact a poorly done insulation job will have on the long-term energy utilization of a home. Start researching insulation solutions early in your remodelling or construction project. It may even help to have an independent third party come in and verify that the insulation was installed correctly. Also, before insulation, the home should be pressure tested, air leaks in the building envelope should be identified, and efforts should be made to seal all gaps around plumbing and electrical penetrations between the attic, garage, crawlspace, and the home.

free hvac tips advice size matters bay area


Improving the insulation in an attic is only part of the story. It is essential to seal up air leaks between the attic and living space before adding insulation.

free hvac tips advice size matters bay area


This is a popular feature that also poses a considerable air leakage pathway between the home and the attic. Air sealed canister light fixtures that are IC (Insulation Contract) rated should be used, but unfortunately, many contractors don’t consider using them because they are more expensive or are unaware of them.

free hvac tips advice size matters bay area


Kitchen range hoods, indoor clothes dryers, and bathroom exhaust fans all contain powerful fans that can cause a tightly sealed home to become slightly depressurized. This can create a safety issue when the negative pressure in the home overpowers the natural drafting of indoor combustion appliances, such as furnaces or fireplaces, and can lead to the accumulation of toxic carbon monoxide, a byproduct of combustion, in the living areas of the home. If your home has indoor combustion appliances, then a worst-case depressurization evaluation of the house is advised.

free hvac tips advice size matters bay area


Out of sight is out of mind, yet these overlooked areas of the home have a massive impact on the quality of air in a home. Due to some fundamental physics and a phenomenon called “the stack effect”, hot air rising through the structure draws fresh air into the house from the crawlspace. It is estimated that 30% of a home’s indoor air comes from the dusty, and frequently odiferous, crawlspace. If your home has a crawlspace, it should be designed for easy access for inspection and maintenance. For new construction, there is no excuse for a crawlspace not to be well lit, dry, clean, and free of debris and dirt. It should be covered with a wall-to-wall, sealed vapor barrier. If you have a finished basement, then exterior waterproofing, insulation, and drainage systems are essential to be designed and implemented well.

free hvac tips advice size matters bay area


Humans are extremely adaptable. Due to this, we can get used to virtually anything, and we sometimes get used to problems in our home that could easily be changed to make our homes more comfortable.

Take the following test to evaluate your home:

Do you know your furnace is running because you can hear it?

Do you turn up the sound on your television because your air conditioner is on?

Do you notice a musty smell when your furnace turns on?

Do you sneeze at home?

Have you ever noticed a blast of cold air coming from your ducts before you furnace starts?

Do you feel better in your home or outside?

Does your furnace or air conditioner turn on and off because it heats or cools your house too quickly?

At Sandium, we design heating and cooling systems that will make your home comfortable, and you may not even notice the system is running. This is the way it should be!


How do you feel in your home? Does your home have unwanted odors? Do you wake up feeling refreshed? If you answer no to these questions, then you may be suffering from air quality problems or poor ventilation. Sandium has developed an AirScan test to identify what is going on in the air in your home.

When you choose Sandium to have your home’s air quality checked and evaluated, we will address exposure to carbon monoxide, air leaks that may be allowing unfiltered contaminants into your home. Whether or not there is sufficient ventilation to bedrooms to provide healthy air quality, stuffy air due to elevated carbon dioxide levels, how well your filter is working and if sub-micron particulates are finding a way around your filter, and many other aspects of home air quality.


We get calls all the time regarding duct cleaning and find that many homeowners believe that they need to clean their ducts regularly as a way to keep their system clean. However, this is not the case.

Your ducts should not be getting dirty!

If they are dirty, then the solution is not cleaning, but an evaluation of the ductwork to find the source of contamination. Sandium offers a complete diagnostic analysis of duct systems. After testing, we provide a duct-sealing service that will stop the source of dirty ducts, and will also make your system more energy-efficient.


free hvac tips advice allergens in your home bay

Living with allergies is often a lifelong challenge. Too often, we focus on addressing the symptoms of our allergy problems without considering conditions in our homes that are making us react.

  • Your indoor air should be healthier than the air outside.
  • Most of us spend at least one-third of our lives in our bedrooms, so it pays to think about how to keep your bedroom air healthy.
  • Are your bedrooms cluttered? This is one of the most important aspects of a healthy home. A clean bedroom, free of clutter, is easy to keep clean and dust-free. A restful eight hours of sleep in a clean bedroom will give your lungs, immune system, and entire respiratory tract time to build up resistance and recover from allergens and environmental stressors. Keep your bedroom clean and simple.
  • Are some rooms damp or musty? Dampness can lead to rampant mold growth and indoor air problems.
  • Some houseplants have been known to improve indoor air quality. But be careful with your plant choices – some plants grown in moist soils that can become a breeding ground for indoor mold growth and large, leafy plants tend to get quite dusty.
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  • Be careful to maintain your fish tanks! We have tested homes and found that poorly maintained fish tanks are an indoor reservoir of mold growth.


What does it mean when I have condensation on my windows?

Condensation on windows is a telltale sign of elevated humidity and poor ventilation in the home. Excess humidity in the air in your home is looking for a cold surface, and windows, especially metal-framed, single-pane windows, are typically the coldest locations in your home, and therefore one of the first places water condenses.

What is the cure?

Our home consultants will typically recommend that you add insulation to walls and ceiling areas. (Think of insulation as a warm down jacket for your home.) If you see mold growth on the exterior walls of your home, especially down lower on the wall or behind furniture, this could be a sign that your indoor humidity is too high and your walls are uninsulated. We encourage our customers to call us anytime for a free evaluation. We have licensed insulation contractors and can provide you with insulation recommendations that will make your home warm and cozy, while reducing your energy bills, along with reducing the chance for water to condense on your walls.

You can improve the ventilation in your bathrooms by installing a quiet and energy-efficient bathroom fan. We also suggest adding a delay timer to the fan, and then running the fan after bathing for at least 30 minutes to remove excess humidity before it has the chance to increase your home’s humidity level.

Unvented, or poorly vented, combustion appliances are not only a real danger because of toxic carbon monoxide, but these appliances also create water vapor that can add to the humidity load of the home. We can test these appliances and make recommendations for simple upgrades that will make a real difference for your home.

Install and use a kitchen exhaust fan. Cooking is one of the major contributors to excess indoor humidity. Removing this excess moisture with a properly-sized and properly-installed kitchen fan will reduce indoor humidity levels.

Older homes were built a bit like Swiss cheese. There are lots of holes in older homes that are the result of plumbing and electrical openings. These holes not only make homes drafty and less energy efficient, but they also allow water vapor from moist crawlspaces to migrate into your home. Crawlspace vapors contain moisture, mold spores, dust, and odors that are best kept in the crawlspace. Our crawlspace remediation teams will recommend sealing gaps and penetrations, and other cost-effective measures to improve crawlspace conditions to make your home healthier.


High energy bills are a sure sign of home performance problems. Although many homeowners are quick to blame the furnace or the windows, after investigating hundreds of homes, we found that often some small changes can have a significant impact on reducing home energy costs.

To improve the energy efficiency of your home, and to reduce your energy bills, we recommend having a comfort specialist do a top-to-bottom evaluation of your home. After we examine your ducts, insulation levels, ventilation rates, thermostat, furnace condition, and air conditioner, we will provide you with cost-effective suggestions that will make your home feel better, and cost much less to run. We offer a free walk-through audit when we visit your home for the evaluation of a new heating and cooling system. For a reasonable fee, we also provide diagnostic testing to calculate duct leakage rates and air leakage coming into your home – so you know precisely, and scientifically, what is going on in your home.


High humidity can be the result of many problems in a home. Most of the excess moisture in a home comes from breathing, bathing, cooking, and crawlspaces. Breathing? Yes, each time we exhale, we are exhausting some water vapor. Small rooms with a few people breathing all night long can create undesirable humidity levels that can cause lots of problems with allergenic mold and dust mites, and condensation on walls and windows. In most cases, the solution to elevated indoor humidity is to improve exhaust ventilation and improve moisture conditions under the home. In some cases, we can design a heating and cooling system that can also serve to dehumidify your home.


Not all contractors are the same. Here are some questions to consider asking when you interview potential contractors.

  • Do you have a permanent place of business, and what is the address?
  • Is your company licensed in California to do heating and air conditioning work? What is your contractor’s license number? Are you licensed to do residential heating and air conditioning work?
  • Does your company carry both general liability and workers compensation insurance, and can you produce current certificates?
  • How long have you been in business?
  • Are your technicians certified by the EPA to handle Freon refrigerant gas?
  • Is your company a member of a national trade association, such as the Air Conditioning Contractors of America or the National Association of Plumbing, Heating, and Cooling Contractors?
  • Do your service technicians have safety testing equipment to detect gas leakage and carbon monoxide spillage?
  • Does your company use an air flow capture hood to assure the proper delivery of air through your duct system?
  • Does your company own a duct pressurization system (called a “duct blaster”) to verify the quality of the ducts against leaks? (The quality of your ducts is as vital as the quality of your furnace and air conditioner. It does not pay to install energy-efficient heating and cooling equipment if your ducts are leaky. Only by duct pressurization testing can the quality of the ducts be confirmed.)
  • How do you calculate the proper size furnace and air conditioner for my home? Can you perform a computerized equipment sizing and selection calculation?
  • Do you take a whole-house systems approach to size equipment? Are there cost-effective ways to improve the energy efficient heating and cooling load on my home while making my home have better air quality and be more comfortable?
  • Can you provide names of satisfied customers in my neighbourhood?
  • Can your company arrange to finance? (Even if you don’t desire to finance, contractors who offer to finance tend to be trusted by lenders and are more established.)
  • What is your guarantee on service repairs – how long is it and does it cover both parts and labor?
  • Do you have a refund policy if I am not satisfied? What is it?
  • Do you have any unresolved complaints with the Better Business Bureau?
  • Are your technicians NATE certified?

free hvac tips advice worried about moldWORRIED ABOUT MOLD

Mold is a symptom of poor moisture control, and you can prevent mold contamination by eliminating excessive moisture. The following conditions often lead to mold problems:


  • If you notice condensation or moisture on windows, walls, or pipes, dry the wet surface immediately and eliminate the moisture source if possible. Condensation can be reduced by carefully managing your heating, ventilation, and air conditioning systems. Increasing air temperature, for example, can help minimize surface condensation. Contact us for more specific advice.
  • When water leaks or spills occur, act quickly! In most cases, mold will not grow if water or dampness is dried within 24-48 hours after a leak or spill. A qualified water exposure restoration expert should be called to dry any affected materials. Contact us for recommendations.
  • After mold has been removed, it is crucial to eliminate the underlying moisture source to prevent re-contamination.
  • Increase ventilation by opening doors and windows when practical and use fans as needed.
  • Cover cold surfaces, such as cold water pipes, with insulation. Cold surfaces cause condensation.
  • Use exhaust fans or open windows whenever cooking, washing dishes, running the dishwasher, etc.


  • Keep indoor humidity below 60 percent, if possible. Between 30 and 50 percent relative humidity is ideal.
  • Install double-pane glass windows to reduce condensation. Condensation runoff from windows can lead to increased humidity and encourage mold growth.
  • Vent moisture-producing appliances, such as clothes dryers and stoves, to the outside where possible. Combustion appliances, such as stoves, produce water vapor and will increase indoor humidity unless vented to the outside. Never allow a contractor to vent anything into your crawlspace or attic. Call us if you have any questions about this.
  • Do not install carpeting in moisture-prone areas (e.g., concrete floors in garages, bathrooms, etc.). In general, wallpaper and carpeting absorb the humidity of the home.
  • Storage materials, furniture, cardboard boxes, and books all contain organic materials that can retain humidity, decrease air circulation, and lead to mold growth. Removing these items will help reduce moisture.


  • The ground should slope away from the building foundation to prevent water from entering and collecting around the foundation. Configure downspouts to drain water away from the foundation.
  • Clean and repair roof gutters regularly.
  • Avoid landscaping requiring excessive irrigation near the house. It can cause elevated moisture levels.
  • Paint protects your home from the elements. Cracks and peeling paint often indicate potential moisture problems. Maintain your home’s exterior to prevent moisture from entering.


  • Keep crawlspaces clean, dry, and free of debris and stored materials. Your crawlspace may be out of sight, but the air that circulates through it is the same air you breathe in your home.
  • Install a sheet of heavy-gauge plastic (called a “vapor barrier”) on the floor of the crawlspace, sealed to the perimeter wall. This will minimize humidity in the crawlspace and your home.
  • Monitor crawlspace humidity with a remote humidity sensor. We can recommend some good sources.
  • Keep air conditioning drip pans clean, and make sure drain lines are unobstructed and flowing properly.
  • Use air conditioners and dehumidifiers if necessary.
  • Change your furnace filter regularly. Make sure the filter is the right size and installed correctly. If the filter doesn’t fit properly, the air will go around it.


  • Keep water and dirt out of your ducts to prevent mold from circulating. If your ducts are dirty, have them repaired and sealed to avoid dust from entering the system. Before buying air cleaners and filters, or cleaning your ducts, eliminate the source of the problem. Contact us for more information.


  • Install and use ventilation fans in all bathrooms. Run the fan or open the window when showering, and leave them running for 30-60 minutes after showering, or until excess humidity is gone.


Out of sight is out of mind, yet these overlooked areas of the home have a significant impact on the quality of air in a home. Due to some basic physics and a phenomenon called “the stack effect”, hot air rising through the structure draws cold air into the house from the crawlspace.

It is estimated that 30% of a home’s indoor air comes from the dusty, and frequently odiferous, crawlspace. If your home has a crawlspace, it should be designed for easy access for inspection and maintenance. For new construction, there is no excuse for a crawlspace not to be well lit, dry, clean, and free of debris and dirt. It should be covered with a wall-to-wall, sealed vapor barrier. If you have a finished basement, then exterior waterproofing, insulation, and drainage systems are essential to be designed and implemented well.

free hvac tips advice too hot too cold bay areaTOO HOT? TOO COLD?


Uneven heating and cooling are one of the most common complaints we hear. This is a particular problem in two-story homes where the second floor is too hot, and the first floor is too cold. Uneven comfort also creates energy waste because homeowners try to compensate by using more energy to heat and cool their problems away, which results in sky-high energy bills.

Our whole-house comfort analysis will pinpoint the reasons why your home is uncomfortable. We are experts at uncovering the cause and providing solutions to uneven heating and cooling problems.

  • Are the registers appropriately sized for the heating and cooling needs of each room?
  • Is the furnace or air conditioner too big or too small?
  • Could simple insulation upgrades be a more cost-effective solution?
  • Is a booster fan required?
  • Is the thermostat in the wrong location?
  • Are the return air ducts sized optimally and located for proper airflow?
  • Is the system designed with sufficient air velocity to provide for proper air mixing?
  • Should dampers be installed or adjusted to provide for better system balancing?

We may recommend zoned heating and cooling solutions so that every room can have its own thermostat. We may also recommend upgrading your equipment to support variable speed motors that can deliver just the right amount of heating and cooling, exactly when you need it.

Sometimes the solution could be ductless heating or cooling system that can provide quiet and energy-efficient heating and cooling, where you need it.

For new systems, Sandium’s installation technicians are experts at designing complete comfort systems that will make every part of your home cozy, comfortable, and energy-efficient.