Dormer Assembly Base Frame Flap Integration for Watertight Roof Transition

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Solution Overview

Problem

The installation of dormer assemblies in pitched roofs often compromises the water tightness and thermal insulation of the roof, and existing methods are not easy to perform effectively.

Innovation Solution

A method involving a base frame with attached flaps from the underroof, insulation material, and a series of trimmers and flashing systems to create a watertight and insulated transition, including the use of insulation frames, waterproof collars, and drainage gutters to manage rainwater and maintain insulation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a hole is made in the roof for installation of a dormer assembly, then the dormer can be installed, but the water tightness of the roof is compromised

Engineering Contradiction:
Improvedormer installationVSAvoidwater tightness
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

Flaps are pre-formed in the underroof material before dormer installation, and these flaps are folded and attached to the base frame members during installation to create integrated waterproofing. This preliminary preparation of flaps allows the waterproofing solution to be built-in during the installation process rather than requiring separate waterproofing steps after the hole is cut.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The flaps act as an intermediary element between the roof opening and the dormer assembly. By folding and attaching these flaps to the base frame members, they create a transitional waterproof barrier that connects the existing roof structure to the new dormer opening, preventing water infiltration at the interface.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Ease of manufacture

If a hole is made in the roof for installation of a dormer assembly, then the dormer can be installed, but the thermal insulating properties of the roof are reduced

Engineering Contradiction:
Improvedormer installationVSAvoidthermal insulation
Core Design Contradiction:
Ease of manufactureVSLoss of energy

Solution Approach 1:

Flaps are pre-formed in the underroof material before dormer installation, and these flaps are folded and attached to the base frame members during installation to create integrated waterproofing. This preliminary preparation of flaps allows the waterproofing solution to be built-in during the installation process rather than requiring separate waterproofing steps after the hole is cut.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The flaps act as an intermediary element between the roof opening and the dormer assembly. By folding and attaching these flaps to the base frame members, they create a transitional waterproof barrier that connects the existing roof structure to the new dormer opening, preventing water infiltration at the interface.

Inventive Principle:
Principle #24Intermediary (Mediator)

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

The method ensures a watertight and insulated installation of dormer assemblies, improving both water tightness and thermal insulation while being relatively easy to perform, by using a combination of base frames, insulation, and flashing systems to manage rainwater effectively.

Implementation Method 1

placing insulation material having a lambda value below 0.1 w/mk, preferably below 0.04 w/mk, below the side members and between the battens for supporting the base frame

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3406818B1Dormer assembly
Publication Date: 2019.06.12 VKR HOLDING AS
  • EP3406818B1 patent drawingFigure 1
  • EP3406818B1 patent drawingFigure 2a
  • EP3406818B1 patent drawingFigure 2b

AI summary

Method of installing a dormer assembly comprising a dormer cheek, an upper section and a lower section, in a pitched roof comprising an underroof, rafters and/or battens, wherein the sections are adapted to adjoin the dormer cheek, the pitched roof and the opposite section. The method comprises the steps of: mounting a base frame, comprising frame members, onto the rafters and/or battens, cutting a hole in the underroof, thereby creating flaps in the underroof extending along the frame members of the base frame, attaching the flaps of the underroof to the base frame members by folding the flaps.