Retrotec USACE - Manual (Page 401)

L1
Appendix L
Some Energy Conservation and Process
Improvement Measures/Opportunities (ECM/ECO)
1 Building Envelope
1.1 Walls
1.1.1 Insulate walls. Retrofi t insulation can be external and internal.
1.1.1a External post insulation makes large savings possible, as this type of insulation contrib-
utes not only to a reduction of the heat loss through large wall surfaces, but also elimi-
nates the traditional thermal bridges where fl oor and internal wall are anchored in the
exterior wall.
1.1.1b Internal insulation is typically done when external insulation is not allowed (e.g., for
historical buildings). Internal post-insulation is usually done by mounting lathes on the
inside of an existing construction. Insulation material is placed between the lathes and
gypsum boards, wood, or other fi nishes. Internal post insulation may involve a risk of
defects in the construction caused by moisture, as the resulting moisture resistance
of the vapor barrier is required to be signifi cantly higher than that of the original con-
struction. Additionally, the insulted space cannot be used as long as the work is in prog-
ress and the inner room measurements are reduced.
1.1.2 Insulate walls using spray-on insulation.
1.1.3 Convert courtyard into an atrium to reduce external wall surface.
1.2 Roofs
1.2.1 Use “cool roof” (high-refl ectance roofi ng material) with reroofi ng projects.
1.2.2 Caulk and weather-strip doors and windows.
1.2.3 Determine roof insulation values and recommend roof insulation as appropriate.
1.2.4 Insulate ceilings and roofs using spray-on insulation.
1.2.5 Exhaust hot air from attics.
1.3 Floors
1.3.1 Insulate fl oors.
1.3.2 Insulate fl oors using spray-on insulation.
1.3.3 Insulate basement wall with a slab over unheated basement.
1.3.4 Create a thermal break around the slab perimeter to decouple slab from wall.