Damp Proofing Plate for Slate Roof Water Ingress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional slate roofing systems are prone to water ingress through the perp joints, leading to capillary action and potential leaks, especially on low-pitched or exposed roofs, which can result in batten and nail rot and roof failure.
Innovation Solution
A roll-formed damp proofing plate is placed between sloping slates to inhibit water ingress, featuring a dividing ridge and V-shaped notches, which increases the gap between slates to over 0.5mm, sealing the perp joint and extending the head lap, and includes deformable outer ridges for a secure seal and drainage channels to prevent capillary action.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If slates are installed with tight perp joins (gap < 0.5mm), then the roof maintains a neat appearance, but capillary action draws water across the slates causing leaks
Solution Approach 1:
A damp proofing plate is introduced as an intermediary element between adjacent slates at the perp join. This plate physically separates the slates to maintain a gap greater than 0.5mm, preventing capillary action while preserving the visual appearance of tight fitting slates. The plate acts as a mediator that solves the contradiction by enabling both aesthetic requirements and water resistance.
2Reliability
If the bond width is increased to prevent water creep, then water resistance improves, but the visible slate margin area decreases
Solution Approach 1:
The damp proofing plate segments the continuous slate surface by introducing a discrete protective element at the perp join. This segmentation allows the bond width to remain narrow (preserving visible margin) while the plate provides the necessary water resistance barrier, separating the functions of aesthetics and protection.
3Reliability
If a waterproofing solution is added to prevent water ingress, then water resistance improves, but the roof structure complexity increases
Solution Approach 1:
The damp proofing plate functions as a thin film or barrier element inserted between slates. This thin-profile solution provides effective waterproofing without adding significant structural complexity, volume, or weight to the roof assembly, maintaining simplicity while solving the water resistance problem.
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 solution effectively prevents water ingress by eliminating capillary action, enhancing weather resistance and allowing installation on complex or low-pitched roofs, while maintaining the aesthetic appearance of a traditional slate roof.
Implementation Method 1
if the gap between the slates is below 0.5mm (Q1), then 'capillary action' will draw the water even further across the slates
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A damp proofing plate installed underneath a first and second sloping slate in a roof, and supported on top of a third sloping slate in the roof. The plate is roll-formed to have a cross-section which comprises a first and second outer ridge and a first and second inner ridge in the direction of the slope of the slates. The first slate from the roof is supported on top of the plate by the first outer ridge and the first inner ridge. The second slate from the roof is supported on top of the plate by the second inner ridge and the second outer ridge. The total height of the plate in its installed state is more than 0.5mm but less than 3mm. The plate inhibits the capillary action between the slates and water ingress in the roof is thereby inhibited.