Module: BTAP::BridgingData

Included in:
Bridging
Defined in:
lib/openstudio-standards/btap/bridging.rb

Overview

—- —- —- —- —- —- —- —- —- —- —- —- —- —- —- #

Constant Summary collapse

MASS2 =

— —- —- —- —- —- —- —- —- —- —- —- —- —- — # BTAP costing data (both original BTAP envelope entries and EVOKE add-ons) hold sub-variants based on cladding/veneer, e.g.:

- "BTAP-ExteriorWall-WoodFramed-5" ... brick veneer
- "BTAP-ExteriorWall-WoodFramed-1" ... wood siding

Not all of these sub-variants are currently used within BTAP, e.g. “BTAP-ExteriorWall-WoodFramed-1” is unused. BTAP/TBD data is limited to the following wall assemblies (paired LP & HP variants), which eventually should be located in a shared file (e.g. CSV, JSON).

-----   Low Performance (LP) assemblies
ID    : layers
-----   ------------------------------------------
STEL1 : cladding | board   | wool | frame | gypsum
WOOD5 : brick    | board   | wool | frame | gypsum
MASS2 : brick    | xps     |      | cmu   |
MASS4 : precast  | xps     | wool | frame | gypsum

-----   High Performance (HP) variants
ID    : layers
-----   ------------------------------------------
STEL2 : cladding | board   | wool | frame | gypsum ... switch from STEL1
WOOD7 : brick    | mineral | wool | frame | gypsum ... switch from WOOD5
MASSB : brick    | mineral | cmu  | foam  | gypsum ... switch from MASS2
MASS8 : precast  | xps     | wool | frame | gypsum ... switch from MASS4

Paired LPs & HPs vall variants are critical for ‘uprating’ cases, e.g. NECB2017/2020. See below, and end of this document for additional NOTES.

"BTAP-ExteriorWall-Mass-2"
MASS2_BAD =

LP wall

"BTAP-ExteriorWall-Mass-2 bad"
MASS2_GOOD =

LP “bad” PSI factors

"BTAP-ExteriorWall-Mass-2 good"
MASSB =

LP “good” PSI factors

"BTAP-ExteriorWall-Mass-2b"
MASSB_BAD =

HP, from @Uo < 0.183

"BTAP-ExteriorWall-Mass-2b bad"
MASSB_GOOD =

HP “bad” PSI factors

"BTAP-ExteriorWall-Mass-2b good"
MASS4 =

HP “good” PSI factors

"BTAP-ExteriorWall-Mass-4"
MASS4_BAD = 
"BTAP-ExteriorWall-Mass-4 bad"
MASS4_GOOD = 
"BTAP-ExteriorWall-Mass-4 good"
MASS8 =

HP, from @Uo < 0.183

"BTAP-ExteriorWall-Mass-8c"
MASS8_BAD = 
"BTAP-ExteriorWall-Mass-8c bad"
MASS8_GOOD = 
"BTAP-ExteriorWall-Mass-8c good"
WOOD5 = 
"BTAP-ExteriorWall-WoodFramed-5"
WOOD5_BAD = 
"BTAP-ExteriorWall-WoodFramed-5 bad"
WOOD5_GOOD = 
"BTAP-ExteriorWall-WoodFramed-5 good"
WOOD7 =

HP, from @Uo < 0.183

"BTAP-ExteriorWall-WoodFramed-7"
WOOD7_BAD = 
"BTAP-ExteriorWall-WoodFramed-7 bad"
WOOD7_GOOD = 
"BTAP-ExteriorWall-WoodFramed-7 good"
STEL1 = 
"BTAP-ExteriorWall-SteelFramed-1"
STEL1_BAD = 
"BTAP-ExteriorWall-SteelFramed-1 bad"
STEL1_GOOD = 
"BTAP-ExteriorWall-SteelFramed-1 good"
STEL2 =

HP from @Uo < 0.278

"BTAP-ExteriorWall-SteelFramed-2"
STEL2_BAD = 
"BTAP-ExteriorWall-SteelFramed-2 bad"
STEL2_GOOD = 
"BTAP-ExteriorWall-SteelFramed-2 good"
ROOF = 
"BTAP-ExteriorRoof-IEAD-4"
FLOOR = 
"BTAP-ExteriorFloor-SteelFramed-1"
@@data =

— —- —- —- —- —- —- —- —- —- —- —- —- —- — # Preset BTAP/TBD wall assembly parameters.

{}

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.extended(base) ⇒ Object 



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# File 'lib/openstudio-standards/btap/bridging.rb', line 540

def self.extended(base)
  base.send(:include, self)
end

Instance Method Details

#costed_assembly(structure = nil, stype = :walls, perform = :lp) ⇒ String

Retrieves BTAP-costed assembly.

Parameters:

  • structure (BTAP::Structure) (defaults to: nil) —

    BTAP Structure object

  • stype (:walls, :floors or :roofs) (defaults to: :walls) —

    surface type

  • perform (:hp or :lp) (defaults to: :lp) —

    high- or low-performance variant

Returns:

  • (String) —

    BTAP assembly identifier for costing



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# File 'lib/openstudio-standards/btap/bridging.rb', line 415

def costed_assembly(structure = nil, stype = :walls, perform = :lp)
  stype   = :walls unless [:roofs, :floors].include?(stype)
  perform = :lp    unless perform == :hp
  return STEL1 unless structure.is_a?(BTAP::Structure)

  # Select BTAP-costed assembly, matching:

  #   - BTAP::Structure generated construction parameters

  #   - requested high (HP) vs low-performance (LP) PSI-factor level

  #

  # Ideally, chosen PSI factor sets and matching OpenStudio constructions

  # shouldn't strictly be based on selected BTAP assemblies (e.g.

  # wood-framed vs steel-framed, cladding choice), but also on selected

  # building 'structure', e.g.:

  #

  #   - "wood-framed" MURB

  #   - "steel post/beam" office building

  #   - "reinforced concrete post/beam" public library

  #   - "metal(-building)" warehouse

  #   - "mass-timber (CLT)" university pavilion

  #

  # Major thermal bridges often consist of anchors or supports that transmit

  # structural loads (and by the same token, 'heat') to a building's main

  # structure. Examples include balconies, parapets and shelf angles.

  # Highly conductive building structures (e.g. steel, aluminium) exacerbate

  # thermal bridging effects - so building structural selection matters.

  #

  # The BTAP::Structure module generates such attributes, yet BTAP's costed

  # thermal bridging database doesn't yet distinguish between building

  # structures - @todo. For the moment, BTAP PSI set selection is strictly

  # based on BTAP::Structure's :framing, :cladding and :finish attributes,

  # which must be set prior to initiating BTAP's TBD's thermal bridging

  # solution:


  # Light gauge steel framing by default. Override if wood, cmu or precast.

  case stype
  when :roofs  then return ROOF
  when :floors then return FLOOR
  else
    case structure.framing
    when :wood
      c1 = WOOD5
      c2 = WOOD7
    when :cmu
      c1 = MASS2
      c2 = MASSB
    else
      if structure.cladding == :heavy && structure.finish == :heavy
        c1 = MASS4
        c2 = MASS8
      else
        c1 = STEL1
        c2 = STEL2
      end
    end
  end

  perform == :lp ? c1 : c2
end

#costed_uo(assembly = "", uo = nil) ⇒ Double

Retrieves nearest assembly Uo factor.

Parameters:

  • assembly (String) (defaults to: "") —

    BTAP assembly identifier

  • uo (Double) (defaults to: nil) —

    target Uo in W/m2.K

Returns:

  • (Double) —

    costed BTAP assembly Uo factor (nil if fail)



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# File 'lib/openstudio-standards/btap/bridging.rb', line 481

def costed_uo(assembly = "", uo = nil)
  return nil unless @@data.key?(assembly)
  return nil unless uo.is_a?(Numeric)

  uo = uo.clamp(TBD::UMIN, TBD::UMAX)

  @@data[assembly][:uos].each { |u| return u if u.round(3) <= uo.round(3) }

  nil
end

#data ⇒ Hash

Return BTAP/TBD data.

Returns:

  • (Hash) —

    preset BTAP/TBD data



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# File 'lib/openstudio-standards/btap/bridging.rb', line 536

def data
  @@data
end

#lowest_uo(assembly = "") ⇒ Double

Retrieves lowest costed assembly Uo factor.

Parameters:

  • assembly (String) (defaults to: "") —

    BTAP assembly identifier

Returns:

  • (Double) —

    lowest costed BTAP assembly Uo factor (nil if fail)



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# File 'lib/openstudio-standards/btap/bridging.rb', line 498

def lowest_uo(assembly = "")
  return nil unless @@data.key?(assembly)

  @@data[assembly][:uos].min
end

#set(assembly = STEL2, quality = :good) ⇒ Hash

Retrieves assembly-specific PSI factor set.

Parameters:

  • assembly (String) (defaults to: STEL2) —

    BTAP/TBD wall construction identifier

  • quality (Symbol) (defaults to: :good) —

    BTAP/TBD PSI quality (:bad or :good)

Returns:

  • (Hash) —

    BTAP/TBD PSI factor set (defaults to STEL2, :good)



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# File 'lib/openstudio-standards/btap/bridging.rb', line 511

def set(assembly = STEL2, quality = :good)
  assembly = STEL2 unless @@data.key?(assembly)
  quality  = :good unless @@data[assembly].key?(quality)

  chx = @@data[assembly][quality]
  psi = {}

  psi[:id          ] = chx[:id          ]
  psi[:rimjoist    ] = chx[:rimjoist    ][:psi]
  psi[:parapet     ] = chx[:parapet     ][:psi]
  psi[:fenestration] = chx[:fenestration][:psi]
  psi[:door        ] = chx[:door        ][:psi]
  psi[:corner      ] = chx[:corner      ][:psi]
  psi[:balcony     ] = chx[:balcony     ][:psi]
  psi[:party       ] = chx[:party       ][:psi]
  psi[:grade       ] = chx[:grade       ][:psi]
  psi[:joint       ] = chx[:joint       ][:psi]

  psi
end