Durisol: Insulated Concrete Form (ICF) Wall Forming System Bruce Coldham, Coldham Architects, LLC www.coldhamarchitects.com Affordable Comfort. - Westford, MA October, 2003
An explanation of the material and assemble of the wall system A discussion of the properties of the wall system Four project case examples 2
Insulated Concrete Form (ICF) Material Shredded (recycled) mineralized wood material Combined in a cementitious slurry and pressed into a wallform block Mineral wool insulation plugs inserted into the core 3
Below grade foundation walls Above grade walls 4
First Course is set out precisely on footing...by masons or carpenters? It is formwork, not a bearing CMU wall. Use string line 5
Wood biscuits to align the interior face. Wallform blocks are dry-stacked 6
Door and window openings 7
Cutting wallforms 8
Steel reinforcing Steel reinforcing bars horizontally and vertically 9
Wall Form Shoring Prevent corner blowouts Prevent uplift and leaking of horizontal joints but this material is much heavier than EPS blocks Align and stabilize the top course 10
Fill core with concrete Pump placement 3,000 psi and pea stone. We laid the wall forms to their full height and poured the core in three lifts (circuits) in a single pumping operation. 11
Wall finishes. and air barrier 12
Exterior wall finishes The wall form material accepts mechanical fastening of wood and other furring materials using screw fasteners. 13
Waterproofing.. 14
Supporting intermediate floors 15
Supporting intermediate floors Ledgers bolted to the concrete core through 5 diameter shear connectors 16
Lintels.. Header beams over rough openings Wallform create reinforced concrete lintels. Wrapped engineered lumber beam ends in wallformed beam pockets. 17
Accommodating electrical circuitry 18
Material properties: 19
Material properties: A reliably well insulated masonry wall Insulation value R 8 to 20 Theoretical insulation value is achievable without requiring heroic oversight 20
Material properties: A non-combustible wall assembly Surface Burning (ASTM-E84) Smoke Developed: 11 Flame Spread Index: 0 UL/ULC (S101) 44 hour rating 21
Material properties: Air and vapor permeable affording a vapor storage potential Vapor Permeability 20.5 (dry) - 26.5 (100%RH) ng / (Pa s m) 14 (dry) - 18 (100%RH) perm - inch Vapor Permeance 1.75 imperial perm for 8 8 block 400-800 ng/(pa s m 2 ) per 50 mm The breathability of the wall system, particularly with a lime-based plaster applied to the interior walls, which maintains the wall s moisture permeability. The exterior wall acts as something of a humidity reservoir with excess humidity taken up by the exterior walls and released back to the interior as interior RH levels diminish. 22
Material properties: No capacity to "lift" moisture through capillary action in the wallform material meaning that the wallform material is a free draining medium No propensity to freeze-thaw damage 23
Material properties: Completely non-biodegradable wall system 24
Material properties: Unable to support the growth of molds and mildew The cementitious matrix is too alkaline Not attractive to termites, but wallform interstices appear to allow passage for termites. 25
Material properties: Sound absorbent Noise reduction coefficient 0.70 to 0.95 sound attenuation properties especially useful in large interior multi-use space. (Leave Durisol material unfinished above 7 ) 26
Material properties: Regionally appropriate material? The wall form seems appropriate use of the mixed hardwood forest produce of the US northeast, which otherwise has limited use in building. 27
Small, Timber Framed House Francestown, NH Completed: 2002 Building Area: 1,500 s.f. Wall system cost: $11/ s.f. Design requirements: Robust, durable support complement for a timber frame 28
Concentrate the frame investment overhead let a less expensive (and more suitable) material be the wall 29
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In this instance, the wallforms were laid up on a conventional concrete foundation wall 31
Great Barrington House Gt. Barrington, MA Completed: 2001 Building Area: 3,500 s.f. Wall system cost: $12/ s.f. Design requirements: Interior floor flows continuous to the exterior. Durable substrate for vegetated walls 32
Great Barrington House Gt. Barrington, MA METAL ROOF VENT SELECT PINE TRUSS RAFTER 1 X 6 WHITE CEDAR T&G BOARDS 5/4" X 2" WHITE CEDAR 2'-0" OVERHANG 5/4" X 14" WOOD FRIEZE BOARD 3/4" PLYWOOD Durisol I.C.F. ROOFING FELT 3/4" C.D.X OR OSB ROOF SHEATHING WOOD ROOF TRUSSES @ 24" o.c. R-40 (12") BLOWN-IN CELLULOSE INSULATION 1 X 3 FURRING @ 16" o.c. 5/8" GYPSUM BOARD OVER POLY. AIR / VAPOR MEMBRANE SEAL AIR / VAPOR MEMBRANE TO WALL PLATE 2 X 10 WALL PLATES 1/2" DIA. ANCHOR BOLT @ 48" o.c. WINDOW BLOCK HARDWOOD WINDOW SILL 1 X 3 WOOD SILL APRON Wall system design options: Conventional stud frame on conc. foundation wall S.I. P. on conc. foundation wall ELEV. MALE - 105'-3" FEMALE - 107'-8" T.R. - 107'-11" EXTERIOR STUCCO DURISOL BLOCK - 300 mm THICK MINERAL WOOL INSULATION INSERT - 80mm CONCRETE INFILL 5/8" GYPSUM WALLBOARD 1 X 4 WOOD BASEBOARD 2" CONCRETE TOPPING SLAB (FINISH FLOOR) 3/4" SUB-FLOOR 9 1/2" TJI JOISTS 1/2" DIA. ANCHOR BOLT @ 16" o.c. 2X6 WALL PLATES WOOD SHINGLES OVER BUILDING WRAP MEMBRANE WOOD FRAMEWALL - 2X6 @ 24" O.C. W/ 1/2" OSB SHEATHING 7" CELLULOSE INSULATION 5/8" GYPSUM WALLBOARD 2 X 3 STRAPPING 1 X 4 WOOD BASEBOARD 1 1/2" RIGID INSULATION THERMAL BREAK 2X6 WALL PLATES WOOD SHINGLES OVER BUILDING WRAP MEMBRANE S.I.P. - 5 1/2" RIGID INSULATION (EPS) W/ 1/2" STRESSED SKIN OSB, BOTH SIDES 5/8" GYPSUM WALLBOARD 1 X 4 WOOD BASEBOARD 1 1/2" RIGID INSULATION THERMAL BREAK 2" CONCRETE TOPPING SLAB (FINISH FLOOR) 3/4" SUB-FLOOR 9 1/2" TJI JOISTS 2" CONCRETE TOPPING SLAB (FINISH FLOOR) 3/4" SUB-FLOOR 9 1/2" TJI JOISTS ELEV. MALE - 96'-8" FEMALE - 99'-1" T.R. - 99'-4" #4 BAR HORIZONTAL REINFORCING #4 BAR VERTICAL REINFORCING WATERPROOFING (BELOW GRADE) 6" FOOTING DRAIN 4" CONCRETE SLAB 1" RIGID INSULATION DAMP-PROOF MEMBRANE 1/2" DIA. ANCHOR BOLT @ 16" O.C. WATERPROOFING (BELOW GRADE) 6" FOOTING DRAIN VERTICAL REINFORCING HORIZONTAL REINFORCING 4" CONCRETE SLAB 1" RIGID INSULATION DAMP-PROOF MEMBRANE 1/2" DIA. ANCHOR BOLT @ 16" O.C. WATERPROOFING (BELOW GRADE) 6" FOOTING DRAIN VERTICAL REINFORCING HORIZONTAL REINFORCING 4" CONCRETE SLAB 1" RIGID INSULATION DAMP-PROOF MEMBRANE 9" X 20" CONCRETE STRIP FOOTING #4 DOWEL BAR #4 HORIZONTAL FOOTING REINFORCEMENT CONCRETE STRIP FOOTING DOWEL BAR HORIZONTAL FOOTING REINFORCEMENT CONCRETE STRIP FOOTING DOWEL BAR HORIZONTAL FOOTING REINFORCEMENT 33
Wholefood farm store Ghent, NY Completed: 2003 Building Area: 9,000 s.f. Wall system cost: $16/ s.f. Design requirements: Rodent exclusion Sound absorption 34
Wholefood farm store Ghent, NY 35
Wholefood farm store Ghent, NY 36
Wholefood farm store Ghent, NY 37
Wholefood farm store Ghent, NY Cement substitution Gran Cement 38
Vipassana Meditation Center Shelburne, MA Completed: Project abandoned Building Area: 30,000 s.f. Design requirements: Durability a building that would last 100 s of years Non-combustibility a large building in an isolated setting Multiple accessibility many on-grade exits and entries Conform to a sloping site 39
Vipassana Meditation Center Shelburne, MA Design opportunity: Use the insulated mass of the structural enclosure to carry the building whilst the heating system is entirely serving the DHW need. The space heating and the DHW loads were similar in magnitude. Therefore a 50% reduction in heating system capacity was possible. 40
The Durisol Corporation www.durisol.com bruce@coldhamarchitects.com www.coldhamarchitects.com 41
Material Properties Modulus of Elasticity (ASTM C513) E=1500 MPa compression Modulus of Rupture (ASTM C293) 1.0 to 3.0 MPa Ultimate Compression Strength (ASTM C513) 1.5 to 3.0 MPa Shear Strength: > 0.2 MPa Durisol to Concrete Bond: > 0.6 MPa 42
Great Barrington House Gt. Barrington, MA 43