INTD 59 mechanical applications

1. INTD 59 mechanical applications

2. ventilation • the effort to decrease energy consumption correlates with the need to manage indoor air quality (IAQ) • careful selection of finish materials • proper use of mechanical ventilation • during a bath/shower humidity level in bathroom can be as high as a rain forest: • uncomfortable, hot, damaging • breeding ground for mold, mildew & microorganisms

3. ventilation • the correct air movement capacity is an important consideration in any bath • typically measured in cubic feet per minute (cfm) • ventilation rates based upon eight air changes per hour are generally suggested • rule of thumb: 1 cfm per sf of bathroom area • bathrooms • 50 cfm (intermittent use) • 20 cfm (continuous use) • CODE: minimum ventilation for the bathroom is to be a window of at least 3 sf of which 50% is operable, or a mechanical ventilation system of at least 50 cubic feet per minute ducted to the outside

4. ventilation • other considerations for ventilation: • an enclosed toilet should have own exhaust fan • fans approved for installation in wet areas should be located over (near) the shower or tub whenever possible • bathroom doors should have at least ¾-inch clearance to the floor to allow for proper entry of makeup air • bathrooms with ceilings higher than 8 feet may require additional ventilation

5. heating location of heat/AC registers, as well as air returns, in a kitchen or bath design plan radiant heated floors—finish floor material? transition of heated floor to adjacent floor? radiant heat lamps—provides warmth to body while drying off convection ceiling heaters—air is moving so it can cause slight cooling effect on wet body radiant wall heaters—not best solution to heating space baseboard heaters—provide general heating of space toe-kick heaters—often used when heat/AC register is in ceiling CODE: all bathrooms should have an appropriate heat source to maintain a minimum room temp of 68 F

6. water heating • accounts for approximately 15% of home’s energy use • high efficiency use 10-15% less than standard—actual savings depend on family size, heater location, size & location of water pipes • storage (tank)—20-80 gallons, “standby losses” • demand (tankless)—circulates water through large coil/limited amount of fixtures that can run simultaneously • heat-pump— transfer energy from surrounding air to water in storage tank/more efficient & most effective in warm climates with long cooling seasons • solar— high initial cost/reduces operating costs up to 90%/requires conventional water heater as back-up

7. sound • noise level is a consideration when selecting bathroom ventilation and fixtures • sound emissions are measured in sones & decibels • sone: a unit of loudness; perceived sound • decibel (dB):measurement of the power or intensity of sound • sounds move within the home either directly or indirectly • shiny, smooth, hard surfaces reflect sound waves • matte, uneven, porous, softer surfaces absorb them

8. sound • fan sound levels measured in sones—1.0 sones or less • (4.0 tv; 3.0 office noise; 1.0 fridge; 0.5 rustling leaves) • since bathrooms typically have majority of hard surfaces, minimizing transmission of sound must always be planned • wall, ceiling & floor insulation • noise stops or sound boards on common walls • sound-absorbing underlayment in floors • insulate water & drain pipes • enclose toilet in separate room • plan ventilation system to operate at 1.0 sones or less • insulate ducts with wrap

9. sound • properly sized ducts • properly sized valves & ducts • a variety of finish materials, with a balance of soft & hard • ample space for towels • radiant heated floor • foaming or sound wrap around outlets & switch boxes