Insulated shell of a frame house

Frame House, 90 m² — Krasny Bor, Leningrad Region

Stage: Closed thermal envelope · Duration: 35 calendar days · Area: 90 m² (8.1 × 12.5 m) · Floors: 1

About the Project

A single-story frame house designed for year-round living, built to the closed thermal envelope stage — a fully sealed, weather-protected shell that allows interior finishing works to continue in any season, regardless of external conditions.

Within 45 calendar days, the Stroy Invest 24 team completed the project from the first pile installation to a finished roof structure: foundation, structural frame, roof system, metal roofing, and exterior wall sheathing with weather protection.

The client received a completed structural shell (“box”), ready for gradual interior completion, allowing flexible budgeting and the opportunity to experience the layout at full scale.

Structural System

Foundation — Reinforced concrete piles
Provide a ventilated crawl space, prevent capillary moisture from the ground, and ensure stability on frost-susceptible soils typical of the Leningrad region without the need for a heavy strip or slab foundation.

Structural frame — Kiln-dried, planed timber
Maintains stable geometry without warping after drying; ensures straight walls ready for finishing. Diagonal bracing provides resistance to wind loads.

Roof structure — Gable roof with a standard pitch
Designed for a snow load of 180 kg/m² and wind load of 30 kg/m² (Climate Zone II, SP 131.13330.2012).

Roofing — Dark graphite metal roofing over Ondutiss Smart waterproof membrane
Protects against condensation from the insulation side and external leaks.

Wall sheathing — OSB / cement-bonded particle boards (CBPB) with vapor-permeable weather barrier
The structure remains breathable while protected from wind and driving rain.

Completed Work Stages

• Site layout and pile foundation installation

• Perimeter beam and structural wall frame assembly

• Roof framing and batten installation

• Installation of waterproof membrane and metal roofing

• Exterior wall sheathing with OSB / CBPB panels

• Installation of wind and moisture protection membrane

Why the Closed Thermal Envelope Stage Is Cost-Effective

Flexible budgeting over time
The most critical stages — structure and roof — are completed first. The project can be paused without risk of moisture damage, while interior work continues later at the client’s pace.

Year-round interior construction
Insulation, engineering systems, drywall, and finishing can proceed regardless of weather conditions.

Full-scale layout evaluation
Before finishing, the client can physically walk through the space, adjust partitions, and refine lighting and furniture placement.

Budget control
Major cost components (foundation, frame, roof) are completed under a fixed estimate, allowing predictable planning for subsequent works.

Result

A completed closed thermal envelope of a 90 m² single-story house, ready for engineering systems and interior finishing. The structure is designed for Northwestern climate loads, built from kiln-dried timber, and protected with a modern membrane system — a durable foundation for a home intended to last for decades.