Introduction Retrofit interior insulation of masonry buildings Exterior insulation ideal solution Interstitial condensation, freeze thaw issues

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Science Corporation Masonry Wall Interior Insulation Retrofit Embedded Beam

joists embedded in masonry structure Reduced heat flow Higher localized relative

Insulation Retrofit Embedded Beams 2 Literature Review (DuMont et al.

Capillarity from foundation? Rainwater absorption through face of masonry?

1 Introduction Retrofit interior insulation of masonry buildings Exterior insulation ideal solution Interstitial condensation, freeze thaw issues Kohta Ueno, Building Science Corporation Masonry Wall Interior Insulation Retrofit Embedded Beam Simulations BEST3 Conference April 2-4, 2012 Moisture sensitive (wood) beams and joists embedded in masonry structure Reduced heat flow Higher localized relative humidity Reduced drying (with low permeance insulations) Masonry Wall Interior Insulation Retrofit Embedded Beams 2 Literature Review (DuMont et al. 2005) In SK (Zone 7B), joists stayed dry (10-15% MC) In ON (Zone 6A), at times 20%+ MC Capillarity from foundation? Rainwater absorption through face of masonry? Masonry Wall Interior Insulation Retrofit Embedded Beams 3 Masonry Wall Interior Insulation Retrofit Embedded Beams 4 Ueno buildingscience.com 1 of 7

Literature Review (Con t) HEAT 3D Three-dimensional simulations Scheffler (2009) DELPHIN 2D hygrothermal simulations, steady state Interior-sourced air and

Historic & modern methods to address beam end MCs Morelli (2010) Gap in insulation above and below beam area (12 above and below 30 left exposed) 60% heat flow

Retrofit Embedded Beams 5 Masonry Wall Interior Insulation Retrofit Embedded Beams 6 Beam Case Simulation Geometries Firecut Beams 78 x 78 (2 m x 2 m) wall /

2 Literature Review (Con t) HEAT 3D Three-dimensional simulations Scheffler (2009) DELPHIN 2D hygrothermal simulations, steady state Interior-sourced air and vapor flow risks Transient simulations; beam end MCs increase w. insul. Historic & modern methods to address beam end MCs Morelli (2010) Gap in insulation above and below beam area (12 above and below 30 left exposed) 60% heat flow reduction from full insulation 45% reduction with gapped insulation Gapped insulation has less wetting than full insulation Masonry Wall Interior Insulation Retrofit Embedded Beams 5 Masonry Wall Interior Insulation Retrofit Embedded Beams 6 Beam Case Simulation Geometries Firecut Beams 78 x 78 (2 m x 2 m) wall / 18 (0.45 m) thick / 12 x 8 (0.3 m x 0.2 m) beam Insulated cases add 2 (50 mm) of closed-cell spray foam Masonry Wall Interior Insulation Retrofit Embedded Beams 7 Masonry Wall Interior Insulation Retrofit Embedded Beams 8 Ueno buildingscience.com 2 of 7

3D Heat Flow Simulations (Beam) Uninsulated Case Insulated Case 3D Heat Flow

Air space and no air space Thinned foam ~16 around beam in all directions 3

Embedded Beams 9 Masonry Wall Interior Insulation Retrofit Embedded Beams 10

Uninsulated Insulated 3 mm plates 78 x 78 (2 m x 2 m) wall / 18 (0.

3 3D Heat Flow Simulations (Beam) Uninsulated Case Insulated Case 3D Heat Flow Simulations (Beam) Thin (1 ) Foam Case 3 mm aluminum plates Interior 68 F (20 C) Exterior 7 F (-14 C) (Boston 99.6% design T) Steady state (no thermal mass). Air space and no air space Thinned foam ~16 around beam in all directions 3 mm aluminum plates, sides of beam, 2x beam pocket interior depth Air leakage and condensation risks? F (6-8 C) 70 F, 35-40% RH) Masonry Wall Interior Insulation Retrofit Embedded Beams 9 Masonry Wall Interior Insulation Retrofit Embedded Beams 10 3D Heat Flow Simulations (Beam) Horizontal Sections (Mid-height) Joist Cases Uninsulated Insulated 3 mm plates 78 x 78 (2 m x 2 m) wall / 18 (0.45 m) thick 2 x12 (0.5 m x 0.3 m) wood members at 16 (0.4 m) o.c. spacing Masonry Wall Interior Insulation Retrofit Embedded Beams 11 Masonry Wall Interior Insulation Retrofit Embedded Beams 12 Ueno buildingscience.com 3 of 7

3D Heat Flow Simulations (Joist) Horizontal Sections (Mid-height) 3D Heat Flow Simulations (Joist) Horizontal Sections (Mid-height) Uninsulated Insulated 3 mm plates Thinned

300 250 200 150 100 50 321 Joist Cases: Heat Flux 57 9% of savings eaten by plates associated with 3 joists (6 plates) 20% of savings eaten by uninsulated band (16% of wall) 81

4 Equivalent IP R-value (h ft 2 F/Btu) Hygrothermal (1D) Simulations One dimensional section same in uninsulated and insulated cases Modify wood material thermal conductivity,

4 3D Heat Flow Simulations (Joist) Horizontal Sections (Mid-height) 3D Heat Flow Simulations (Joist) Horizontal Sections (Mid-height) Uninsulated Insulated 3 mm plates Thinned Foam Omit band insulation Masonry Wall Interior Insulation Retrofit Embedded Beams 13 Masonry Wall Interior Insulation Retrofit Embedded Beams 14 W flux (4 square meters) Joist Cases: Heat Flux 57 9% of savings eaten by plates associated with 3 joists (6 plates) 20% of savings eaten by uninsulated band (16% of wall) Equivalent IP R-value (h ft 2 F/Btu) Hygrothermal (1D) Simulations One dimensional section same in uninsulated and insulated cases Modify wood material thermal conductivity, to result in correct beam end temperatures Needed to develop a temperature index at end of beam pocket from HEAT3 simulations 0 Uninsulated Insulated Al Plates Uninsul Band Masonry Wall Interior Insulation Retrofit Embedded Beams 15 Masonry Wall Interior Insulation Retrofit Embedded Beams 16 Ueno buildingscience.com 4 of 7

Beam End Temperature Index Hygrothermal (1D) Simulations Uninsulated ~60% T inboard of pocket Insulated ~90% T inboard of pocket Air leakage (source) from interior Beam end element plotted wood MC

Boston (cold year) Interior T: 68 F/20 C Interior RH: 30% winter to 60% summer Northeast orientation Less T across masonry Less inward vapor drive Lower summertime MCs Air leakage into now-colder

5 Beam End Temperature Index Hygrothermal (1D) Simulations Uninsulated ~60% T inboard of pocket Insulated ~90% T inboard of pocket Air leakage (source) from interior Beam end element plotted wood MC (outermost 1 /25mm) Masonry Wall Interior Insulation Retrofit Embedded Beams 17 Masonry Wall Interior Insulation Retrofit Embedded Beams 18 Uninsulated Beam Results Insulated Beam Results Exterior: Boston (cold year) Interior T: 68 F/20 C Interior RH: 30% winter to 60% summer Northeast orientation Less T across masonry Less inward vapor drive Lower summertime MCs Air leakage into now-colder beam pocket (would be worse at higher wintertime RHs) Air change plays role in drying of beams in existing buildings? Masonry Wall Interior Insulation Retrofit Embedded Beams ACH = m/s air velocity (1/3 in & 1/3 out) Masonry Wall Interior Insulation Retrofit Embedded Beams 20 Ueno buildingscience.com 5 of 7

Alternate Masonry Assemblies Alternate Masonry Assemblies Results Air leakage (source) from interior Masonry Wall Interior Insulation Retrofit Embedded Beams 21 Masonry Wall Interior Insulation

6 Alternate Masonry Assemblies Alternate Masonry Assemblies Results Air leakage (source) from interior Masonry Wall Interior Insulation Retrofit Embedded Beams 21 Masonry Wall Interior Insulation Retrofit Embedded Beams 22 Conclusions: Thermal simulations (2D) Addition of insulation makes ends of embedded wood members colder in winter Metal plates add heat at beams; risks of condensation and air leakage Thinned insulation shows little effect on beam end temperatures Elimination of rim joist insulation results in higher beam end temperatures, but with an energy performance penalty Conclusions: Hygrothermal simulations Air leakage has a strong effect on beam end moisture contents likely occurring in reality Airflow lowers moisture content in some cases, but can raise MC in wintertime (insulated case vs. uninsulated with airflow) Alternate material assemblies can have strong effect on results Substantial uncertainty in actual behavior simulations here were a workaround Use of 2-dimensional hygrothermal simulations? Field monitoring of actual behavior (wood MCs) New structure inside? Use of hygric diode material? Masonry Wall Interior Insulation Retrofit Embedded Beams 23 Masonry Wall Interior Insulation Retrofit Embedded Beams 24 Ueno buildingscience.com 6 of 7

7 Future Work (Beam MC Monitoring) Beam damage w/o insulation Masonry Wall Interior Insulation Retrofit Embedded Beams 25 Masonry Wall Interior Insulation Retrofit Embedded Beams 26 Questions? Kohta Ueno This presentation will be available at BSC s website: Masonry Wall Interior Insulation Retrofit Embedded Beams 27 Ueno buildingscience.com 7 of 7

Background. Embedded Wood Members Monitoring Research (Canada) In SK, joists stayed dry (10-15% MC) In ON, sometimes up to 20% MC

Background. Embedded Wood Members Monitoring Research (Canada) In SK, joists stayed dry (10-15% MC) In ON, sometimes up to 20% MC Hygrothermal Analysis Expert Session Simulations and Reality November 19, 14 Kohta Ueno Embedded Wood Joists in Insulated Masonry Walls-Simulations & Reality November 19, 14 Background 2 Embedded Wood