Alumasc’s Technical Director Mark Gibbs discusses what specifiers should look for in their EWI system for high-rise and the importance of safe installation.
Specification for the multi-storey application of External Wall Insulation is very different to that of low-rise projects, with health and safety procedures being a key consideration in the thermal upgrade of high-rise buildings.
High rise projects for the last 25 years have been refurbished using EWI, as a cost effective method of achieving thermal and aesthetic upgrade of buildings.
EWI solves the issue of condensation, water ingress and poor thermal performance of many of the blocks and provides a U-value to comply with current Building Regulations.
The appropriate type of EWI insulation board is mechanically and adhesively fixed to the substrate to achieve the thermal requirements of the project. A polymer modified reinforcing base coat, incorporating a fibreglass reinforcement mesh, is then applied.
Various finishes are available, ranging from traditional dash or painted renders to more modern through-coloured silicone renders, once it has fully cured.
The insulation boards of high-rise EWI specification must be adhesively and mechanically fixed. To accommodate higher wind loads, calculations must be made and the edge zones, and increased mechanical fixings are required for external corners and openings.
The calculations must always be conducted by Structural Engineering Consultants to ensure structural stability, required performance and system longevity.
For use in high-rise application, specified EWI systems must be officially accredited and approved. The system requires a large scale fire test or reaction to fire test when used above 18m in height.
There are additional detailing considerations compared to low-rise, as well as through-the-wall square metre rates. Including parapet, lightening conductor, CCTV, external lights, robust window cill details, ground floor entrance areas etc.
It is critical that all detailing is robust and installed as per specification .Any repairs are more difficult and costly to address than for low-rise projects once the wall access is removed. Scaffold ties should be fixed in the most practical locations and protected scaffolding is recommended.
Mast climbers are an economical and faster track option for EWI install, however they offer less protection to newly installed work. Programming considerations should always allow for weather conditions.
White House Works,
Phone: 01744 648400
Full-service agency MRA Marketing has been shortlisted for 15 awards across 10 categories in this year’s prestigious Construction Marketing Awards (CMAs).Posted in Articles, Awards, Building Associations & Institutes, Building Industry Events, Building Industry News, news
There are a range of hands-free door opening solutions – available to suit all budgets and needs – that can help minimise the spread of infection, says the ASSA ABLOY Door Hardware Group.Posted in Access Control & Door Entry Systems, Architectural Ironmongery, Articles, Building Industry News, Building Products & Structures, Doors, Health & Safety, news, Security and Fire Protection
Leading life-safety systems manufacturer, C-TEC, has created a new Evacuation Alert Systems video.Posted in Articles, Building Industry News, Building Services, Facility Management & Building Services, Health & Safety, Security and Fire Protection, Video of the Week
As the UK moves towards net-zero carbon emissions by 2050 and an ever-growing demand for housing, Baxi has launched a suite of products and services for heating and hot water systems – Baxi Assure.Posted in Articles, Building Industry News, Building Services, Heating Systems, Controls and Management, Heating, Ventilation and Air Conditioning - HVAC, Innovations & New Products, Posts, Sustainability & Energy Efficiency