Insulation and Ventilation

Baffles are commonly used to provide how many inches of space?

1 inch

Sheathing and veneer require how much air space?

1 inch

What is the minimum clearance for insulation to sheathing (near vents)?

1 inch

What is the minimum dimension opening for roof ventilation with mesh screening?

1/16

What size sheathing do many builders use and what is the R-value?

1/2 sheathing 0.6 R Value

Underfloor openings that are screened and grated required how much of an opening?

1/4 inch

What is the minimum access of a crawlspace at the perimeter wall?

16 x 24

What is the minimum size for an underfloor crawlspace opening?

18 x 24

Crawlspace ventilation is a minimum of 1 square foot per ______ square feet.

1:150

1 square foot of net vent opening with vapor retarder =

1:300

An attic with an area of 600 square feet with ridge and soffit vents should have a total of how many square feet?

2 square feet

What is the minimum access to an attic opening and what is the minimum requirement of headroom above the hatch?

22 x 30 30 inches of headroom

What is the distance required when a crawlspace has 1 vent opening?

3 feet of each corner

To figure out fiberglass insulation's R-Value, what do you multiply the thickness by?

3.2

In an attic, what is the service area required in front of mechanical equipment?

30 x 30

How many cups of water can enter through a 1/2 inch round hole via air transportation in a year?

50

What is the minimum R-Value of insulation required for ductwork?

6

How many inches should joints of a vapor retarder overlap?

6 inches

What type of barrier would cover a wall filled with insulation?

6 mil poly

What provides the most effective ventilation?

A combination of ridge vents along the peak of the roof and continuous soffit vents at the eaves

Is it more important for the air barrier or the vapor barrier to be continuous?

Air barrier

What controls the movement of air through a building assembly, such as a wall?

Air barrier

What type of leakage can go through building assemblies and move large quantities of water vapor and is a major factor in many vapor related moisture problems?

Air leakage

What prevents water vapor in the air from entering the wall assembly?

Air sealing

If the crawlspace isn't ventilated, where might you have insulation installed.

At the perimeter wall (joist rim band)

Where is the best place to find air leaks and seal them up?

Attic

What can be used to prevent loose-fill insulation from blocking the attic vents.

Baffles or Rafter vents

What type of insulation is used for Cathedral ceilings?

Baffles or batten insulation

Where can blankets, batts and rolls be inserted?

Between studs and floor joists

If there isn't any insulation in the attic space, then where should insulation be installed?

Between the joists

If there isn't any insulation in the attic space, where should insulation be installed?

Between the joists

Stachybotrys fungus is known as what kind of mold?

Black mold

What promotes the most air restriction?

Caulking

Heat is always trying to escape to _______.

Cold

What is the best term that describes the transfer of heat from one molecule to another?

Conduction

The term used describe how heat rises and moves with air is described as ________.

Convection

What is the purpose of a high and low vent?

Encourage air movement through the attic

What system provides a controlled way of ventilating a home while minimizing energy loss?

Energy recovery ventilation

In a typical residential air conditioning system, what absorbs the heat energy from the air passing through it?

Evaporator

What is mold a sign of?

Excessive moisture

What increases heat loss, promotes condensation and can cause excessive depressurization, leading to air leakage from the house to the attic?

Excessive ventilation

Where does moisture tend to go in hot humid climate?

Exterior to interior

What is placed along the back of the wall below grade for the purpose of frost control?

Extruded foam insulation

Which material has the highest R-value?

Fiberglass insulation

Why should kraft paper or standard foil vapor diffusion retarder facing on the blanket insulation be covered with gypsum or interior paneling?

Fire Hazard

If the crawlspace elevation is below the exterior finish grade, what should be provided in a fashion similar to that required for basements?

Foundation drainage and foundation wall damp-proofing (ground vapor barrier)

What is the best way to check for loose flashing and trim?

Grab it and pull it away

What type of insulation is used to spray and inject wall cavities?

High density and low density polyurethane

What is the primary cause of many vapor related moisture problems in homes?

High indoor humidity

What results would an inspector anticipate seeing if insulation was added improperly to an attic?

Increased cooling efficiency

What is a good practice when there is insulation installed and it's near the top of the joists?

Install new batts perpendicular to the existing ones to cover the top joists and reduce thermal bridging

What is required if ducts pass through an unconditioned, unheated space, such as an attic?

Insulation

What should be a concern of an inspector who notices a skylight on a roof?

Insulation

What should be located at the entrance of a pull down attic hatch or door?

Insulation

In basements, why should low permeability and continuous vapor retarders on the interior side of basement finishes be avoided?

It can trap moisture vapor moving through the foundation

What is the benefit of adding more insulation where you already see insulation, such as in the unfinished attic floor area?

It will likely reduce energy bills

What is the best way to minimize ice damming?

Keep the attic as cold as possible with good soffit venting

When installed incorrectly, what can vapor retarders trap?

Moisture

On a flat roof, where will you most often see vents?

Opposing fascias

What kind of duct system would have a large rectangular duct that comes out of the heating system and runs in a straight line down the center of the basement?

Plenum Duct System

What do soffit vent baffles do?

Prevent insulation from covering vents

What type of air mixes with gas before going to the burners?

Primary

What is the total R-Value for loose fiberglass when you see about inches of thick insulation at the floor of unfinished attic?

R-15

10 inches of fiberglass insulation provide a thermal resistance (R-Value) of how much?

R-30

What is the required R-Value of insulation for duct in attics?

R-8

What is the R-Value of 12 inches of loose fiberglass insulation?

R30

What is the term used to describe the transfer of heat energy by electromagnetic wave motion?

Radiation

What refers to the amount of moisture contained in a quantity of air compared to the maximum amount of moisture the air could hold at the same temperature?

Relative Humidity

What is the most effective venting system?

Ridge and soffit vents

Where is a good place to insulate in the basement?

Rim/band joists

What controls the concentration of pollutants in the room they were emitted into and minimize the spread of pollutants into other parts?

Spot ventilation

What type of material can both air seal and insulate?

Spray foam insulation

How should insulation be handled around metal vents?

The metal vents should be contained in a box and kept away from insulation

What can be stopped by installing insulation in the attics and covering the tops of the attics floor joists?

Thermal bridging

What term best describes moisture in a vapor state moving from a warm part of an assembly to the cold part of the assembly?

Thermal diffusion Heat diffusion

Why shouldn't power vents operate in the winter?

They can depressurize the attic increasing heat loss

What is a building code requirement regarding joints in duct systems?

They must be substantially airtight

How to vapor diffusion retarders work?

They only retard moisture via diffusion

What material impedes the flow of moisture vapor through the vapor material?

Vapor barrier

What old term refers to controlling moisture?

Vapor barrier

What is required below any slab intended as a floor for habitable space?

Vapor barrier/retarder

What is another word for vapor barrier?

Vapor retarder

What is defined as having <1 perm based on a scale of permeance levels?

Vapor retarder

What is intended to control the entry of water vapor into a building assembly by vapor diffusion?

Vapor retarder

What is required for Cathedral roof venting?

Vent baffles installed between the insulation and the roof decking to ensure proper ventilation

What may not be sufficient enough to prevent moisture and condensation in the attic?

Ventilation

What type of vents are required for a pitched roof?

Vents along the eaves or Passive vents

Should the vapor barrier be on the warm side or the cold side of the wall assembly?

Warm side

What moisture prevention is recommended as best practice for basements that are intended to be used for storage or living space?

Waterproofing

When is an unvented conditioned attic permitted?

Where there is no vapor retarder applied to the floor of the attic, but insulation is applied to the underside of the roof deck.

What is the problem with insulation that is compressed?

Will not produce its full R-value

What type of insulation is hazardous around knob and tube wiring?

any insulation that is not in a metal box

In a heating only climate, what would an uninsulated heating duct running through a garage deliver to the room at the end of the duct?

cool air

What does damage from ice dams typically indicate?

insufficient attic insulation

In most cold climates, where should the vapor diffusion retarder be placed?

on the warm side

Which way should a vapor diffusion retarder face on insulated ductwork?

outside

Describe a few possible ways to get a look at insulation in a flat roof?

remove ceiling light fixture, exhaust fan covers or popping fascias off and looking through holes