Roof Window Installation Immersed in Structure
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Solution Overview
Problem
Existing roof window installation systems suffer from heat loss due to thermal bridges formed by fixing runners and hinges, which protrude above the roof surface, compromising thermal insulation efficiency.
Innovation Solution
A roof window installation system where the window frame and sash are immersed in the roof structure with hinges positioned above the glazing unit, ensuring at least 90% of the glazing unit's thickness is within the roof structure, and additional thermal insulation is used around the window frame during installation, eliminating thermal bridges and enhancing insulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If fixing runners penetrate the roof structure perpendicularly to fix the window frame, then the window frame can be securely fixed, but thermal bridges are formed causing heat loss from the attic
Solution Approach 1:
The harmful thermal bridge effect is extracted and eliminated by removing the perpendicular penetration of fixing runners through the roof structure. Instead, the runners are positioned parallel to the roof surface, taking out the problematic thermal conduction path while preserving the window fixing function through alternative mounting arrangements.
Solution Approach 2:
An intermediary thermal insulation layer is introduced between the fixing runners and the roof structure to mediate the thermal interaction. This intermediary layer blocks the direct thermal conduction path while allowing the mechanical fixing function to be maintained, thus resolving the contradiction between secure mounting and thermal insulation.
2Ease of operation
If hinges are immersed into the window between side members of frame and sash, then the pivot window can rotate properly, but metal hinges form thermal bridges causing heat loss
Solution Approach 1:
The harmful thermal bridge effect is extracted by removing the traditional immersed hinge configuration. The hinges are repositioned above the glazing unit, taking out the problematic thermal conduction path through the window while maintaining the pivot rotation function through alternative hinge mounting positions that do not penetrate the thermal insulation layers.
Solution Approach 2:
The hinge position is changed from a vertical immersion through the window frame to a horizontal positioning above the glazing unit. This dimensional repositioning moves the thermal bridge away from the critical heat flow path through the window, allowing proper rotation while reducing thermal loss.
3Ease of manufacture
If significant part of window frame protrudes above roof surface, then the window can be easily installed and accessed, but heat escapes from attic through the protruding frame
Solution Approach 1:
The window frame configuration is modified to have different local qualities at different positions. The frame is designed to minimize protrusion above the roof surface while maintaining adequate accessibility for installation and operation. This localized optimization reduces the thermal bridge area while preserving the necessary installation characteristics.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration significantly reduces heat flow from the attic to the outside, as illustrated by lower temperature gradients and heat flux densities, resulting in improved thermal performance and reduced thermal losses by 37.5% compared to traditional systems.
Implementation Method 1
additional thermal insulation is used around the window frame during installation, eliminating thermal bridges and enhancing insulation
Data Source
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AI summary
A system for window installation in the roof is characterised in that when the window is closed, the glazing unit (11) of the window is immersed in the roof structure, so as to at least a half of thickness (G) of the glazing unit (11) is situated in the roof structure deeper than the surface (PP) called "sub-cover surface" of structural elements of the roof, the surface having roofing mounted, for instance surface of battens (41), on which roofing tiles (42) are mounted. In the pivoting hinges (3), connecting the window sash (1) with the window frame (2), centres of mass of the elements (31) of these hinges, which are connected with the sash, are situated above the external surface of the glazing unit (11), when the window is closed.