Sustainability

Nearly 40% of global carbon emissions stem from the building sector.

More details to come soon, but we estimate that by using hemp-lime as insulation, along with other sustainably-minded decisions like an increased percentage of fly ash in the concrete, we were able to cut the embodied carbon of the Cape Cod Hemp House by nearly half when compared to a conventional home.

Below are just some of the decisions and substitutions made when considering the sustainability of this incredible house.

Check back soon for a more streamlined experience.

Item
Division
Specification
Replacing
Implemented
Notes
Environmental or Health Concern Mitigated
Budget impact
Trash
General
C&D Waste diversion program
C&D Waste to landfill
Yes
Landfill burden, waste of materials and invested energy
Minimal
Drain piping
Sitework
HDPE or ABS pipe
PVC
Partial
Partially implemented, PVC is the industry norm
PVC is carcinogenic. Manufacturing and disposal issues
Minimal
Demolition
Sitework
Salvage Program
Yes
Local salvage organization "Green Goat" performed
Landfill burden, waste of materials and invested energy
Possible cost savings
Cement mix (Piers & Slabs)
Concrete
Set max. allowance for portland cement, substituted with fly ash and/or slag
Portland cement
Manufacturing portland cement accounts for approximately 5% of the anthropogenic CO 2 emissions worldwide
?
Slab base
Concrete
Foamed glass aggregate
Crushed rock, Rigid foam insulation
Yes
For use at insulated slabs, replaces crushed rock and eliminates foam insulation
Eliminates global warming impact of foam insulation. Reuse of waste product (glass).
Grout mix
Masonry
Set max. allowance for portland cement, substituted with fly ash and/or slag
Portland cement
Yes
"
?
Masonry block (CMU)
Masonry
Jandris reduced portland cement CMU
Portland cement
No
Product unavailable at time of construction. "CarbonX" carbon sequestering blocks also unavailable
"
?
Structural steel
Metals
Low emission manufacturing plant sought out
No
Unavailable
High embodied energy of fabrication
n/a
Structural steel
Metals
Recycled content
-
Yes
Steel incorporates high amount of recycled content by default
High embodied energy of steel, iron mining and production
None
Rot resistant lumber - interior
Wood
ACQ (Alkaline Copper Quarternary)
CCA
Yes
CCA is mostly phased out, use is regulated
CCA (chromated copper arsenate) contains arsenic, known carcinogen
None
Decking, pavers
Wood
Black Locust
Tropical Hardwood
Yes
Appalachain material, does not have potential rainforest deforestation of tropical hardwoods
Rot resistant lumber - exterior
Wood
Red cedar, Black locust, Redwood
ACQ (Alkaline Copper Quarternary)
Yes
ACQ on the exterior can leach into surface waters, marshes or coastal areas and is toxic to aquatic life.
?
Triforce joists
Wood
Open web joists reduce material and OSB
TJI's
OSB offgas VOC's
Minimal to none
Subfloor
Wood
T&G plywood instead of OSB
OSB offgas VOC's
Minimal to none
Cladding
Wood
Eastern White Cedar shingles
Varies
Yes
Local, renewable material does not require painting
Cabinets
Wood
PureBond core: Formaldehyde free, made in US, soy based adhesives
Sub slab insulation
Thermal & Moisture
Foamed glass aggregate
Crushed rock, Rigid foam insulation
Yes
For use at insulated slabs, replaces crushed rock and eliminates foam insulation
Eliminates petroleum based foam insulation. Reuse of waste product (glass)
Insulation- flat roofs
Thermal & Moisture
Vacupor vacuum panels
Rigid foam insulation
Yes
R20+ per inch
Alternative to foam insulation
Metal roofing
Thermal & Moisture
Zinc
Aluminum, asphalt shingles
Yes
Lower embodied energy than aluminum. Durable and recyclable material.
Air and weather barrier
Thermal & Moisture
Lime render air and water barrier
Building wrap, spray foams
Yes
No on site spray foam (offgassing, installer exposure to chemicals) or use of petroleum based products. Material is fully continuous when applied and does not rely on adhesives that may fail
Rigid insulation
Thermal & Moisture
Recycled foam insulation
New material
Yes
Limited use of foam where substitutes could not be applied
Reused material - no new foam manufactured. No onsite spray foam
Minimal
Insulation- walls and roof
Thermal & Moisture
Hemplime
Spray foam insulation
Yes
Yes, some use of reclaimed rigid foam and mineral wool at basement walls
Replaces petroleum based foams, many of which use ozone deplete blowing agents and are hazardous to install, with a zero carbon material. Can improve indoor quality - mold & pest resistant.
Acoustic insulation
Thermal & Moisture
Hempwool
Fiberglass batts
Yes
Carbon sequestering and non toxic.
Vapor barrier
Thermal & Moisture
15mil. taped seams and perimeter
5mil
Yes
Heavy duty, taped barrier maximizes effectiveness to maintain good indoor air quality
Joint sealers
Thermal & Moisture
Tremco and AFM Safecoat
Varies
Low / Zero VOC reduces chemical offgassing
Glazing
Doors and Windows
Triple glazed with warm spacer, Low E
Double glazed Low E
Yes
Improved thermal performance
Windows and doors
Doors and Windows
Duratherm
Varies
Yes
Domestic manufacturer, unit longevity
Hardware
Doors and Windows
Merit Metal
Varies
Yes
Domestic manufacturer
Windows and doors
Doors and Windows
FSC Mahagony exterior, Red Oak interior
Varies
Partial
FSC mahagony exterior and interior due to availability
Sustainably sourced materials, Local material for interior
Painting
Finishes
Integral color or Lime paint finish
Varies
VOC free finish
Plaster
Finishes
Lime plaster
Gypsum board
Yes
Naturally mold resistant due to alkalinity, durable, doesn't require paint finish
Stains and sealers (floors, stone, etc)
Finishes
Low or VOC free
Varies
Low / Zero VOC reduces chemical offgassing
Trellis fabric shades
Specialties
Exterior shading solution to prevent solar heat gain in the house during summertime
Glass wall system
Specialties
Tubelite Recycled Aluminum frame
Storefront
Recycled aluminum frame lowers embodied energy
Acoustic rubber tile
Specialties
Smash tile by Ecore
Yes
Recycled rubber
Fireplace
Specialties
Sparatherm Vario
Varies
Among lowest emission unit on the market
Resilient clips
Specialties
Hushframe
Reslient metal channels
Yes
Wood and silicone as opposed to metal (lower embodied energy)
Cooktop
Equipment
Induction
Gas
No combustion in house improves air quality. Induction reduces waste heat and size of ventilation required
Shade fabric
Furnishings
Lutron fabrics PVC free
PVC blends
Yes
PVC is carcinogenic. Manufacturing and disposal issues
Ventilation
Mechanical and Plumbing
Zehnder ducted ERV
Central ERV
Yes
Distributed system for fresh air throughout the house
Piping
Mechanical and Plumbing
Cast iron and copper
Pex and PVC
PVC is carcinogenic. Manufacturing and disposal issues
Fixtures
Mechanical and Plumbing
Watermark
Varies
Domestic manufacturer
Heating and Cooling
Mechanical and Plumbing
Air Source Cold Climate Heat Pumps
Gas boiler/furnace
No
All electric, highly efficient cooling and heating
Generator and Battery
Electrical
Generac
Varies
Awaiting DC generator that can charge batteries along with PV
Reduced reliance on natural gas generator, and on grid, through addition of battery system
Solar PV system
Electrical
LG Panels
Varies
PV is key strategy towards Net Zero energy goal. Reduces demand/reliance on grid supplied power
Wiring
Electrical
Romex - Could not find LBC complaint alt
PVC sheath. PVC on red list