- Residential >
- Commercial >
- Electrical Services
- water heaters
- HVAC Parts
- Residential >
- Commercial >
- Electrical Services
ATTIC, BATHROOM AND WHOLE HOUSE FANS
Valley can furnish and install three types of fans for your home:
- Attic Fans – Solar and Electric
- Whole House Fans – Increase the efficiency of your air conditioning unit
- Bathroom Fans
WHY CHOOSE VALLEY HEATING, COOLING, Electrical?
Why should you consider an attic fan?
You may not spend much time thinking about attic ventilation, but if you own your own home, you owe it to yourself to give the subject serious thought. Here is what an attic fan can do for you:
Suppress Heat Build Up
A hot attic acts like a giant radiator, transferring heat into your living spaces, sending both utility bills and temperatures soaring. In colder climates, heat build-up in an attic causes snow to melt and run down where it freezes at the eaves, causing destructive ice damming.
- Reduces heat build up.
- Reduces air conditioning costs.
- Prevents ice damming
- Battle Moisture
Many of today’s houses have insufficient ventilation and air exchange. This causes high humidity levels from everyday activities. This moisture migrates through the ceiling towards the roof where it comes in contact with the cold structure. Here, ice and frost form, causing damage to your roof structure. Additionally, moisture can saturate insulation, promote fungal decay and plywood delamination.
- Reduces damaging condensation.
- Protects insulation from moisture saturation.
- Fights mold and fungal decay.
- Reduces heating costs.
Attic fans are thermostatically controlled so they run only when they’re needed. When you consider that attics can reach 150 degrees Farenheit and that attic heat accounts for 20 percent of the average cooling bill, these fans are a good investment. The cost of installing and wiring an attic fan ranges from $300 to $800. Attic-ventilation fans are also available with humidistats as well as thermostats. A humidistat-equipped fan is a good choice for controlling excess attic humidity during the colder months.
Common signs of an overly hot attic are asphalt shingles with corners curled up, or bulges in the felt and shingles directly over the seams in the sheathing. On cold winter days, look for frost inside the attic. This frost is trapped moisture, which, if not allowed to escape, can rot the entire roof.
Choosing Your Fan
There are two basic attic fan designs: those made for roof installations and those intended to be mounted in a gable wall. Roof installations can be electric or solar.
Solar Star’s Roof Mount Attic Fan is the ideal ventilation solution. Solar Star, the leader in solar powered attic ventilation, brings you the most technologically-advanced, environmentally-friendly, ventilation solution today. Best of all, Solar Star brings you the solutions that cost nothing to operate. Imagine the savings.
By placing the unit on the highest point on the roof where it is most effective, it can properly circulate air and ventilate your attic space, transforming your home into a comfortable living environment. Powered by Solar Star’s proprietary 10-watt solar panel, this breakthrough product has been designed to last season after season. Optional Thermal Switch available for all models.
Roof mounted fans are mounted on plastic or sheetmetal bases that serve as flashing. To install your new fan, we will cut an opening in the roof, typically near the peak, and install the fan over the opening.
Gable-wall fans are slightly easier to install because no shingles are disturbed. In fact, we can simply install your fan in place of an existing gable vent. We may need to enlarge the opening a little to accommodate a slightly larger, automatic shutter, but it is still a fairly simple job, requiring no structural alterations. If your existing vent is large enough, you may not need to replace it. We can just mount the fan directly behind it. With these fans, the wiring is the most expensive part of the job. Solar fans are a little more expensive upfront, but there is no cost to operate.
DUCT CLEANING WITH TRUCK MOUNTED POWER VACUUM
At Valley we furnish and install many makes and models of bathroom fans. Once we evaluate your project, we will recommend the best fan fit for your needs.
How to Size a Bathroom Ventilation Fan?
As the trend to larger spa-like bathrooms continues to gain in popularity, the need for proper ventilation becomes more important. While many people are tired of their noisy and ineffective bath fan – not many people know how to properly size a fan to their needs.
There are a few different ways to calculate the number of cubic feet per minute (CFM) of air movement needed to properly ventilate a bathroom. Make sure you check out the end of the article and read about static pressure. A long duct run from the fan to the outside can skew your calculations.
This method works on the assumption that the goal for bathroom ventilation is 8 complete air changes per hour. Take your square footage x ceiling height to get the total cubic feet to be ventilated. Example: Bathroom measures 10 feet wide and 12 feet long. It has 8 foot ceilings. So 10 x 12 x 8 = 960 cubic feet.
We take the cubic feet and divide by 60 - which is the number of minutes in an hour. We take the result and multiply by 8 (remember, our target is 8 complete air changes each hour). The complete equation is as follows:
10 ft X 12 ft X 8 ft = 960 cubic feet.
960 divided by 60 = 16.
16 x 8 = 128
So – we need 128 CFM of air movement to properly ventilate this bathroom. Assuming there is not and excessively long or twisting duct run to the outside – we would select a fan that moves somewhere around 130 CFM or higher.
This method is a simple one for bathrooms under 100 square feet. According to guidelines of HVI (Home Ventilating Institute), baths 100 square feet or smaller require one CFM per square foot of bathroom – with a minimum of 50 CFM.
So – if you have a 7 foot by 9 foot bath – you need 63 CFM. It doesn’t get any simpler than this. Most conventional ceiling insert fans, however, are rated either 50 or 80 CFM – so you will have to round up or down (rounding up preferred).
This method of calculation is designed for bathrooms over 100 square feet and factors in the number of fixtures in the bath (toilets, showers, tubs). The rules are:
Allow 50 CFM for each standard toilet, shower or tub
Whirlpool and jetted tubs need 100 CFM
So – if you have 1 toilet (50 CFM), 1 shower (50 CFM) and 1 whirlpool tub (100 CFM) – you will need a 200 CFM Fan.
Static Pressure and Duct Run:
A ventilating fan must overcome resistance when pushing air from the inlet, through the duct, to the outside of the building. This resistance is known as static pressure. The amount of static pressure depends on the duct length, type of duct, elbows and the roof jack or wall cap. Essentially, the more elbows, turns, duct length, etc. that you have – the more static pressure will be present and less effective CFM you will get out of your fan.
Panasonic provides some tools to calcuate the model needed to ventilate properly after factoring in duct length, duct type, elbow, type of exterior vents, etc. As you might suspect – the end result of the calculations only leads you to select their fans. While it is possible to use air duct calculators and other tools to precisely determine effective CFMs you will get out of a fan – it is probably OK to simply round up to a larger fan if you know you don’t have a straight duct run to the outside.
Why Use An Inline Fan for Bathroom Ventilation?
There are many options when replacing an old, noisy, ineffective bathroom fan. It’s possible to replace a traditional ceiling-mount bathroom fan with a new fan just like it, or you can replace the old fan with an inline fan system.
An inline fan does not rest directly on the ceiling of the bathroom. Rather – the fan installs in the attic space above or slightly away from the bathroom. An inline fan has several advantages over a traditional bathroom fan:
- POWER - because the fan can be mounted anywhere in the attic – the power of the fan is not limited by the space where it is installed
- SOUND - because the fan can be mounted many feet away from exhaust point on the ceiling – fan vibration and noise is kept to a minimum. The insulated ductwork used in an attic will protect from condensation and provides an excellent sound dampener
- MULTIPLE EXHAUST POINTS - in a larger bathroom, it is possible to create multiple exhaust points in the ceiling and only install one fan. This is done with a WYE connector, some flexible ductwork and multiple grilles. Grilles are available in many shapes and sizes and can also be purchased with lights.
Why Do I Need Ventilation?
With new technology, homes today are designed to be airtight and more energy efficient than ever before. While this results in fewer drafts and lower heating and cooling bills, the airtight design does not allow for proper ventilation of harmful pollutants that can accumulate in a home. Over time, stale air contaminated daily by a collection of pollutants, has proven to be harmful for the people and animals living in the home.
Sources of pollution extend far past the obvious chemicals like paint fumes, asbestos and pesticides. Cleaning fluids, building materials and preservatives used in furniture and carpets can all contribute to poor indoor air quality. Also, everyday items like hairspray, oven cleaner and bug spray can add to this toxic mixture of trapped pollutants.
To some degree, biological pollutants such as mold, mildew, pollen and dust are found in all homes. These biological pollutants thrive in moist, humid environments. These minor hazards, when in large quantities, not only create poor air quality, but can also reduce the structural integrity of a home. Proper ventilation can nearly eliminate these threats and create cleaner, safer air conditions.
MORE ABOUT HOME VENTILATION
Continuous and intermittent mechanical ventilation are two types of approaches commonly used for combating poor air quality. Each kind of ventilation has a specific purpose depending on whether you are ventilating a specific room or the whole house.
Intermittent ventilation, sometimes called spot, local or secondary ventilation, is used to capture and remove moisture or odors quickly at the source. The purpose is to exhaust pollutants before they can spread to other parts of the home. Areas that might require this type of ventilation include the bathroom, kitchen, utility room, exercise room, workshop and home office.
Continuous ventilation, also referred to as general, central, whole-house or primary ventilation, removes stale air and may provide fresh air to all rooms on a slow continuous basis. A well-designed airtight home should include a mechanical continuous ventilation system.
© 2018 All Rights Reserved. Developed by ConsultPR.
Serving South Bay Area and Surrounding areas, including San Jose, Cupertino, Mountain View, Los Altos, Sunnyvale, Los Altos Hills, Milpitas, Los Gatos, Saratoga, Palo Alto, Morgan Hill, San Martin, Gilroy, Santa Clara, Redwood City, Atherton, San Carlos, Monte Sereno, Stanford, Foster City, Belmont.