ABOUT EXPERIMENT PARTNER AND PRODUCT
The wooden prefabricated buildings by RIKO HIŠE combine quality living, economy, and environmental friendliness, following sustainable construction guidelines.
MEASUREMENT & VERIFICATION (PM&VL 9)
The PM&VL9 is built on a deep understanding of the performance of wood-based envelope elements and structures. It focuses on specific issues, properties, and performances of wooden structures, addressing essential requirements—from fire reaction to sustainability, including environmental footprint considerations.
PARTNERS
Scientific partner
ZAG Institute
Industrial Partner
Riko Hiše
Main author:
Barbara Treppo Mekiš,
M. Sc., Civ. Eng.
ZAG Institute
The sustainable prefab wooden external cladding components by RIKO Hiše underwent testing, including exposure to accelerated aging. Visual inspections assessed potential deterioration, particularly moisture-related damage around fasteners.Additionally, tests compared the hail resistance and impact resistance of aged versus unaged elements to evaluate durability under different conditions. Most of the methods used are based on existing standards and procedures described in EOTA TRs and EADs but can be adjusted to specific needs and in most cases adapted and further developed to fit to the purpose of the testing for the specific tested product. These comprehensive analyses ensure the high performance and resilience of the cladding components over time.
Design of Experiments
1- Hygrothermal behaviour acc. EAD 040083-00-0404 Paragraph 2.2.6.
2- Impact resistance acc. EAD 040083-00-0404 Paragraph 2.2.8 on aged and on as delivered samples.
3- Hail resistance acc. FM Approvals 4473 on aged and on as delivered samples.
Tested specimens:
Tongue and Groove Boards (above) and Wooden Slats with Dilatation (below) by RIKO Hiše
Results
Visual inspection after artificial ageing: The wood showed minor colour changes, slight chipping, and raised knots on less than 0.01% of the surface. Traces of water retention were noted at cladding joints, with more moisture observed in the configuration without gaps. No serious wood deterioration was found.
Minor discolorations and chipping after artificial ageing.
Impact resistance: The damage caused by steel ball impacts depends mainly on impact energy, but also on wood quality, and density. Artificial aging has little effect. Edges are most vulnerable, possibly disadvantaging wooden slats with dilatation compared to tongue and groove boards.
Minor dent and discoloration at the point of impact of the steel ball.
Hail resistance: The damage caused by ice ball impacts of varying sizes and masses depends more on the wood’s quality and density at the impact point than on the ice ball’s size or mass. Artificial aging appears to have little effect on the degree of damage. The edges of the wooden claddings are the most vulnerable areas, potentially putting wooden slats with dilatation at a disadvantage compared to tongue and groove boards in terms of hail resistance.
Minor dent and edge chipping at the point of impact of the ice ball.
Conclusion
All tests, simulations, and calculations confirmed the tested product’s suitability for its intended use. The only unexpected finding was that, during impact and hail resistance testing, the extent of damage was influenced more by the wood’s density at the point of impact than by the impact energy.
Open Innovation outcomes
The research activity was conducted exclusively between ZAG and RIKO Hiše. The results will be shared in the RIKO Hiše catalogue and on their website, primarily for marketing purposes, rather than with a focus on an Open Innovation approach.
CONSTRUCTION SEGMENT
TEST CATEGORY
Hygrothermal, Impact and Hail
DATE
06 October, 2025