Friday 24 January 2014

Insulation – it’s more than what meets the eye

Building insulation refers broadly to any object in a building used as insulation for any purpose. Predominantly used for building insulation it adds to the building’s comfort and energy efficiency. Thermal insulation is the second most commonly used insulation wherein materials are used to reduce the rate of heat transfer. Soundproofing, also known as acoustic insulation ensures that the intensity of sound is reduced. Electrical insulation uses material to resist the flow of electric current and magnetism while another means is insulated glass which also saves energy. In recent times fire insulation and impact insulation (e.g. for vibrations caused by industrial applications) also play a vital role. The latest entrant in insulation is Fiberglass insulation, a man-made mineral fiber constructed from a variety of materials, such as sand and recycled glass. More than 90 percent of homes in America are lined with this pink stuff thus emerging as the most popular form of insulation in the United States. As the benefits stand, there are many apprehensions about the damage fiberglass can cause over time. It is known to cause health problems like immediate skin irritation, and some researchers fear inhaling fiberglass particles could cause cancer.

Insulating our buildings is one of the most imperative parts of any construction as insulation has a big effect on the cost of energy. As we have learnt in school heat naturally flows from a warm space to a cool space, and our homes and work places suffer from this transfer. Warm air from the inside will move to the outside and make us cold in winter. In contrast hot air moves from the outside to the inside and makes it uncomfortably warm in summer.

Unless your home and workplaces were specially constructed for energy efficiency, you can possibly reduce your energy bills by adding more insulation. Several older buildings have less insulation than buildings built today, but fret not, adding insulation to a newer building can pay for itself within a few years. To determine whether you require additional insulation, estimate how much insulation you already have in your building and how it is spread out. Invest in a home energy audit or an energy assessment. It will also help identify areas of your home that are in need of air sealing. An insulation check done as a routine part of a whole-house energy assessment done by a certified home energy auditor will also come in handy. One golden rule to remember is that before you insulate, you should make sure that your home is properly air sealed.

Fortunately we have heating and air conditioning systems to fix these problems, but the more opportunities warm air gets to flow out of or into the house, the harder those systems have to work. As those systems work harder, we use more energy and pay much higher utility bills. That is why HVAC insulation services sustain comfortable temperature indoors, with their manifold options. The best suited in terms of the return on investment (ROI) is the HVAC insulation through reflective insulation made by the sandwiched model of aluminium foil and polyethylene bubbled film. Available in two different variants of single bubble insulation and double bubble insulation films, the later one gives you the better protection against the needs of HVAC insulation because of its twin layered of polyethylene bubbles that responds very slow against the unwanted temperature change.

Proper HVAC insulation system is fundamental for homes and industrial constructions for its two prong benefit, it not only saves good amount of money by reducing the energy consumption but it also helps to reduce greenhouse gases released in the atmosphere, which is the need of the hour.

Thursday 9 January 2014

Ventilation

Ventilation (the V in HVAC) is the process of "changing" or replacing air in any space to provide high indoor air quality (i.e. to control temperature, replenish oxygen, or remove moisture, odors, smoke, heat, dust, airborne bacteria, and carbon dioxide). While heating and air-conditioning are relatively straightforward operations, the more complex processes involved in ventilation are the most important in determining the quality of our indoor air.

It is one of the most significant engineering controls available to the industrial hygienist for improving or maintaining the quality of the air in the occupational work environment. It is a means of controlling the environment with air flow. Ventilation also assists in removing unpleasant smells and excessive moisture, introduce outside air, to keep interior building air circulating and to prevent stagnation of the interior air. Ventilation is addressed in specific standards for houses, offices, general industry, shipyard employment, long shoring, and the construction industry. Currently a number of well-identified illnesses, such as Legionnaire’s disease, asthma, tuberculosis, the common cold, influenza, meningitis, hypersensitivity pneumonitis and humidifier fever, have been directly traced to specific building ventilation problems. These are called building-related illnesses and are increasingly predominant in common buildings and workplaces today. Most of these diseases are treatable but some pose grave health risks and may require prolonged recovery times, most often long after the person has left the building.

There are many types of ventilation options –

Single - Sided Ventilation: limited to zones close to the openings

Cross - Ventilation: two or more openings on opposite walls - covers a larger zone than the single-sided openings

Stack Ventilation: Buoyancy - driven gives larger flows

Windcacthers: Wind and buoyancy driven-effective in warm and temperate climates

Solar - induced Ventilation: using the sun to heat building elements to increase buoyancy – more effective in warm climates

Mechanical or forced ventilation: through an air handling unit or direct injection to a space by a fan. A local exhaust fan can enhance infiltration or natural ventilation, thus increasing the ventilation air flow rate.

Natural ventilation: the airflow is due to wind and buoyancy through cracks in the building envelope or purposely installed openings.

Mixed Mode Ventilation or Hybrid ventilation: uses both mechanical and natural ventilation processes. The mechanical and natural components may be used in conjunction with each other or separately at different times of day.

Mechanical exhausts control odors and humidity in kitchens and bathrooms. Ceiling, table, floor fans circulate air within a room for the purpose of reducing the perceived temperature because of evaporation of perspiration on the skin of the occupants. When creating an energy-efficient, airtight home/ workplace through air sealing, it's very important to consider ventilation. Unless properly ventilated, an airtight home can seal in indoor air pollutants. Opening doors, windows, and using ceiling fans are all ways to maximize natural ventilation and reduce the risk of airborne contagion. Natural ventilation requires little maintenance and is inexpensive. Ventilation also helps control moisture, which is another important consideration for a healthy, energy-efficient home.

Good ventilation is matter of great criticality, ISO 16813:2006 is one of the ISO building environment standards, applicable to new constructions and the retrofit of existing buildings.  “It considers the need to provide a healthy indoor environment for the occupants as well as the need to protect the environment for future generations and promote collaboration among the various parties involved in building environmental design for sustainability.”

If you or others at your home/office are experiencing health or comfort problems that you suspect may be caused by indoor air pollution, you can talk to other family members or colleagues to see if similar problems are being experienced by others and contact a HVAC specialist immediately.