Pitched Roof

A pitched roof is a roof structure where the load-bearing and enclosing functions are performed by an inclined truss system, along with nailed perpendicular roof sheathing or rafters made from timber. The truss system distributes wind loads and the roof's own weight across the entire load-bearing perimeter of the building, while the sheathing serves as the base for installing the roofing material, protecting the entire structure from atmospheric exposure.

Insulation material is typically installed between the rafters to ensure a comfortable indoor climate in the attic space. However, if the attic is not used as a living space, insulation may be omitted, relying instead on insulating only the floor between the living level and the attic.

Common Types of Pitched Roofs

Single-slope roofs are most commonly used on non-residential buildings such as garages, warehouses, and utility sheds. In residential construction, pitched roofs are used where local regulations prohibit snow and rainwater runoff onto roads or sidewalks. The roof slope directly depends on the type of roofing material used. For example, metal roofing requires a minimum slope of 35 degrees, while in regions with heavy precipitation, a slope of at least 45 degrees is recommended.

Single-slope roofs can be ventilated or solid (non-ventilated), with no air gap or airflow within the roof assembly. The solid version is cheaper to build but less effective in terms of thermal performance.

Ventilated pitched roofs include an air cavity between the vapor barrier and insulation layer, created by intake openings near the eaves and exhaust vents at the ridge. The pressure difference caused by height variation between these two points drives airflow through the roof structure.

Gabled roofs are among the most popular choices among private builders. This design features two inclined roof planes supported by the building’s perimeter. Their popularity stems from efficient use of attic space, which can be used for living, storage, or utility purposes. Gabled roofs commonly use semi-rigid and flexible roll or board-type insulation materials.

Attic (mansard) roofs are an enhanced version of standard gabled roofs. Internal walls are supported by struts that transfer rafter loads and lift the roof up by 1–1.5 meters. This design makes the attic more practical for furniture placement and daily use.

Other rare or exotic types include hipped, multi-gabled, four-slope, and domed roofs.

Construction Process for Pitched Roofs

Building a pitched roof can be clearly divided into a sequence of steps, each following the other in a fixed order. Here’s a brief overview.

Truss System

Constructed from timber with cross-sections of 100×150 mm or 100×200 mm. Consists of intersecting beams with notches at connection points to the wall plate and to each other. The top edges of the trusses are connected by a ridge beam. After installation, either solid or spaced roof sheathing is applied, serving as the base for roofing material.

Roof Insulation

Next, the roof must be thermally and hydraulically insulated. A vapor barrier membrane is installed over the rafters, secured with a construction stapler with a minimum 15 cm overlap between sheets. Insulation boards made of glass wool or mineral wool are placed tightly between the rafters beneath the membrane.

Roofing Installation

Roofing materials such as bituminous shingles or metal roofing are installed last, as it is technically easier to install insulation and secure the vapor barrier and counter-battens from above than to work from below in the attic space.