Architects and homeowners increasingly turn to passive house design for warm climates as a way to reduce energy consumption while maintaining comfort. One project that exemplifies how sustainable principles can merge with accessible design is the PATCH House in Guayllabamba, Ecuador, designed by ESEcolectivo Arquitectos. Built in 2016, this 230 m² residence sits on a single level and uses rammed earth walls, recycled windows, and reclaimed doors to create a home that wastes almost nothing. The project began with a simple instruction from the client: find solutions for the house on one single level. This request came from the need to provide comfortable access for herself and her mother, who lived in an adjacent house. The design team responded by clearing earth from the building footprint and using that same soil to construct the primary structural walls.
Single-Level Floor Plan Strategies for Accessible Living
A single-level layout eliminates stairs and step changes that create barriers for aging residents or those with mobility challenges. The PATCH House demonstrates how this decision shapes the entire building form. The architect arranged a 230 m² floor plan as a single horizontal sweep, with private spaces on both wings and a central common area. This configuration mirrors principles found in the modern barnhouse vision where open circulation and ground-level accessibility drive the spatial organization.
Zoning the Single-Story Home
Dividing a single-level house into public and private zones requires careful placement of walls and circulation paths. The PATCH House uses a simple C-shaped layout to create distinct areas without long corridors.
- Private wing A houses the quilting studio, main bedroom, and laundry room
- Private wing B contains three guest rooms arranged as compact sleeping spaces
- Central zone functions as an open living and dining area
- A private garden connects visually to the private wing through recycled windows
Accessible Path Widths and Door Clearances
Doorways in accessible single-level homes should measure at least 900 mm wide to accommodate wheelchairs and walkers. Hallways need a minimum clear width of 1200 mm. The recycled doors used in the PATCH House were restored and hung from concrete beams, preserving their original dimensions while meeting functional clearance requirements.
Rammed Earth Construction Techniques for Structural Walls
Rammed earth construction compresses moist soil inside formwork to create dense, load-bearing wall panels. The technique dates back thousands of years but remains relevant for modern sustainable building. The PATCH House used earth excavated from the building site to construct three-meter-tall mud walls arranged in a C-shaped configuration. This shape provides the structural rigidity that rammed earth requires, since unsupported straight earth walls lack lateral stability.
Soil Composition Requirements
Not every soil type works for rammed earth construction. The ideal mix contains approximately 70% sand and gravel, 30% silt and clay, with no more than 5% organic matter. Too much clay causes cracking during drying. Too little clay leaves the wall with insufficient binder to hold particles together.
| Soil Component | Ideal Percentage | Effect on Wall Quality |
|---|---|---|
| Sand and gravel | 60-75% | Provides compressive strength and reduces shrinkage cracking |
| Silt | 15-25% | Fills gaps between larger particles for denser packing |
| Clay | 5-15% | Acts as natural binder that holds the wall together |
| Organic matter | Below 5% | Decomposes over time, creating voids that weaken the wall |
Formwork and Compaction Methods
Rammed earth walls require sturdy formwork that can withstand the force of mechanical tamping. Forms are typically made from plywood or steel, braced every 600 mm to prevent bulging. Soil is placed in 100 mm to 150 mm lifts and compacted with pneumatic tampers until the layer reaches about half its original thickness. A well-compacted lift produces a density of 1800 to 2200 kg/m³, giving rammed earth walls a compressive strength of 2 to 4 MPa – adequate for single-story residential structures.
Thermal performance is another advantage. A 400 mm thick rammed earth wall provides a thermal delay of 10 to 12 hours, meaning heat from the sun takes that long to reach the interior. In warm climates like Guayllabamba, this shifts peak cooling loads away from daytime hours and reduces the need for mechanical air conditioning.
Recycled Windows and Doors in Building Envelopes
The client for the PATCH House followed a personal philosophy of recycling everything possible, a principle that extended directly into construction. Almost all windows, doors, and cabinets came from her previous home. The design team adapted these salvaged components into new openings within the rammed earth walls and concrete beam structure. This approach required creative problem-solving since salvaged units rarely match standard rough openings. The window selection for the farmhouse projects shows how matching window styles to structural openings affects both aesthetics and performance.
Joining and Adapting Found Windows
Recycled windows rarely come in matching sizes. The PATCH House team joined multiple salvaged window units together and adapted them to fit between wooden columns and the mud walls. This patchwork approach created a collage effect on the garden-facing elevation, where the private wing opens outward through a composition of mismatched but functional window assemblies.
Restoring Doors for New Structural Contexts
Doors salvaged from the previous home required restoration before installation. The team removed old paint, repaired rot damage, replaced broken hardware, and rehung each door from concrete beams rather than traditional wooden headers. Old gates and fences were repurposed to enclose the new garden, further extending the recycled material strategy.
How Showcase Homes Inspire Real-World Design Choices
Residential projects like the PATCH House demonstrate that sustainable construction does not require exotic materials or specialized supply chains. The design team used locally available soil, on-site labor, and materials the client already owned. This approach aligns with broader trends in residential architecture where showcase homes inspire real-world design by proving that thoughtful material choices can replace expensive finishes.
- On-site earth excavation provided all material for structural walls
- Recycled window assemblies created a unique garden elevation at no additional material cost
- Restored doors eliminated the need for new millwork purchases
- Reused gates and fences defined garden boundaries without new lumber
- Salvaged cabinets were rebuilt and adapted to new room dimensions
Cost Implications of Salvage-Based Construction
Construction cost data from projects that use significant salvaged materials shows savings of 15% to 30% on finish carpentry, doors, windows, and cabinetry. Labor costs may increase by 5% to 10% because of the additional time needed to sort, clean, repair, and adapt salvaged components. The net result typically reduces the total project budget by 8% to 15% compared to using all-new materials of equivalent quality.
When to Demolish Versus When to Salvage an Existing Structure
Not every old building deserves preservation. Structural damage from termites, dry rot, foundation settlement, or seismic events can make demolition the safer and more economical choice. The PATCH House client did not demolish her previous home – she relocated its usable components into a new structure built on vacant land. This strategy is different from renovation, where the original building remains standing. Builders should evaluate existing structures against clear criteria before deciding which path to follow. Sometimes it is better to demolish an old house than to attempt repairs on a compromised structure.
| Condition | Salvage Recommended | Demolition Recommended |
|---|---|---|
| Foundation cracks | Minor surface cracks under 3 mm | Horizontal cracks or displacement over 10 mm |
| Wall framing | Localized dry rot affecting single studs | Widespread termite damage across multiple walls |
| Windows and doors | Functioning units with cosmetic wear only | Frames with active rot or failed sealants |
| Roof structure | Localized leaks with sound rafters | Sagging ridge line or multiple failed trusses |
| Plumbing | Galvanized pipes with pinhole leaks | Cast iron drain lines with collapsed sections |
When demolition is necessary, contractors should still salvage reusable materials before the wrecking crew arrives. Doors, windows, cabinets, light fixtures, hardwood flooring, and dimensional lumber can be removed and stored for future projects. Many communities have architectural salvage yards that purchase these materials, offsetting demolition costs by 10% to 20%.
Thermal Mass and Climate Response in Earth-Constructed Homes
Rammed earth walls provide significant thermal mass that moderates indoor temperature swings. In Guayllabamba, where daytime temperatures reach 25°C and nighttime lows drop to 10°C, the 400 mm thick walls absorb heat during the day and release it during cool nights. This passive thermal regulation keeps indoor temperatures within a comfortable 18°C to 24°C range without mechanical heating or cooling for much of the year.
Orientation and Shading Strategies
The C-shaped layout of the PATCH House orients the open end of the C toward the garden, allowing northern light to penetrate the central living space while the rammed earth wings provide shade to the outdoor areas. The recycled window collage on the garden elevation maximizes daylight while the solid earth walls on the outer perimeter reduce heat gain from the afternoon sun.
Humidity Control in Earthen Buildings
Rammed earth walls naturally regulate indoor humidity through a process called hygroscopic buffering. The clay component absorbs moisture from the air when humidity rises and releases it when the air becomes dry. This keeps indoor relative humidity between 40% and 60% – the ideal range for human comfort and indoor air quality. In Quito’s subtropical highland climate, where humidity fluctuates seasonally, this passive control reduces the risk of mold growth and condensation on interior surfaces.
Homeowners considering earth construction should also study how passive house design and construction applies thermal mass principles to different building systems. The combination of rammed earth walls, recycled building components, and accessible single-level planning creates a home that is both environmentally responsible and functionally adapted to the occupants’ needs over time.