Breathing Sheathing Board Jargon Buster

GBE > Encyclopaedia > Code > Jargon Buster > Entries > B > G#17097

About:

GBE Jargon Buster

Breathing Sheathing Board Jargon Buster

A board which is vapour permeable enough to allow it to be used externally in timber frame construction.
(GreenSpec AEP ’09)

Used in Breathing wall and breathing roof construction outside of the structural frame, outside of the thermal insulation layer and inside the weather protection.
(NGS BRM ‘10 – GBE BRM ’18)

Breathing:

Can replace the breather membrane and the wind tightness layer in a vapour-open hygro-thermal moisture movement designed system
Some boards have weather tolerant outer faces, (limited time only)
- Most do not and need to be protected
Some materials have hygroscopicity and will manage moisture vapour, reduce risk of condensation and lower the humidity of the air in the construction
Can be the substrate for a moisture permeable external render system
Can be the substrate for counter-battened and battened tiled, slated, shingled or shaked pitched roofing
Can be the substrate for counter-battened and battened weatherboarding and rain-screen boarding
Could also be the substrate for a moisture permeable internal plaster system

Sheathing:

Some boards offer racking strength to stiffen up light timber frame or light metal frame construction
Some boards do not

Insulating:

Can provide some or all of the thermal insulation needed above or outside of the structural framing
Some materials offer thermal conductivity against winter heat loss
Some materials offer decrement delay against summer radiant heat gains
Some materials offer thermal breaks outside of thermal bridge framing
Some materials offer acoustic insulation too

Rigid Board

Not to be confused with plastic insulation ‘rigid boards’
Can be secured to the outside of moisture permeable masonry
Cab be secured to the outside of Cross Laminated Timber Panels CLTP walls and pitched roofs
Can be secured to and span between framing systems
Can be the substrate for a moisture permeable external render system
Can be the substrate for counter-battened and battened tiled, slated, shingled or shaked pitched roofing
Can be the substrate for counter-battened and battened weatherboarding and rain-screen boarding
Could also be the substrate for a moisture permeable internal plaster system
Usually Tongue & Groove Jointed to improve airtightness and minimise thermal bypass
Can be multi layer and staggered to minimise thermal bypass

(GBE BRM ’18)

GBE Jargon Buster Theme

Timber Frame Wall Insulation
CLTP Cross laminated Timber Panel Insulation
Solid Masonry Construction Insulation

GBE Jargon Buster Initial, Abbreviations & Acronyms

BSB Breathing Sheathing Board
BSIB Breathing Sheathing Insulating Board
BSIRB Breathing Sheathing Insulating Rigid Board

GBE Materials:

Dense Wood Fibre
Not Bitumen Impregnated Fibre Board (BIFB)

GBE Classification

CAWS 1987
- K11 Rigid Sheet Flooring/Sheathing/Decking/Sarking/Lining/Casing
CAWS 2012
- 25-80-72 Render and roughcast coating systems
- 25-80-76 Rigid sheet cladding systems
- 25-80-95 Weatherboarding systems
- 25-85-60 Plaster coating systems
- 25-90-50 Metal lathing and anchored mesh reinforcement systems
- 25-90-90 Wall sheathing systems
Uniclass I
- JK11 Rigid Sheet Flooring/Sheathing/Decking/Sarking/Lining/Casing