Sealing High-Temperature Devices

Detail ID
3.0102.2
Topic
General Pressure Boundary
SubTopic
Specific Air Sealing
Desired Outcome

Fully adhered, airtight, fire safe, and durable seal that prevents air movement @ 50 Pascals of pressure

SF Single Family Site-Built Housing
MH Manufactured Housing
MF Multifamily Housing

Specifications

  • SF
  • MH
  • MF
Specification Objective

Select sealants that:

are compatible with their intended surfaces,

allow for differential expansion and contraction between dissimilar materials,

meet the requirements of the applicable fire safety code (e.g. thermal or ignition barriers) and are rated for the operating temperature of the device they are in contact with, and

for use inside the pressure boundary select low volatile organic compound (VOC) sealants that meet independent testing and verification protocols

Select safe and effective sealants

  • SF
  • MH
  • MF
Specification Objective

Select materials that:

adequately support applied load and are permanent air barriers,

meet the requirements of the applicable fire safety code (e.g. thermal or ignition barriers) and are rated for the operating temperature of the device they are in contact with, and

for use inside the pressure boundary select low volatile organic compound (VOC) materials that meet independent testing and verification protocols

Select safe and effective materials

  • SF
  • MH
  • MF
Specification Objective

Maintain a minimum clearance of 3" between combustible materials or sealants and any portion of the high-temperature device (e.g. chimney, vent, flue)

Install a rigid, fixed dam higher than the insulation while that maintains a minimum 3" clearance between high-temperature devices and combustible materials

Do not allow combustible insulation between a high-temperature device and a dam unless insulation material is rated for contact with the device

Prevent fire hazards

  • SF
  • MH
  • MF
Specification Objective

Install non-combustible backing or infill in any gap or crack greater than 1/4"

Install rigid non-combustible backing or infill for gaps or cracks greater than 1" using mechanical fasteners

Once installed, backing or infill will not bend, sag, or move

Prevent excessive sealant movement

  • SF
  • MH
  • MF
Specification Objective

Remove any material from the sealing area that will prevent full adhesion of the selected sealant

Surface is clean and ready to accept sealant

  • SF
  • MH
  • MF
Specification Objective

Apply a continuous seal at all seams, cracks, joints, edges, and penetrations of the sealing area while applying sufficient pressure to push sealant into any gaps or cracks and contact any backing or infill material required

Fully adhered sealant