StubGuard® – A thermal & fireproofing housing to add to the unique Sapphire balcony anchor system

Whilst the thermal values which need to be achieved apply to the whole building not isolated components, to meet Part L regulations, and the requirements of other standards, all balcony connections must have a thermal break to stop cold bridging occurring at these junctions.

Firstly, consideration must be made of the quantity of anchors which are being used. Quite simply, the more points the facade is penetrated the more potential areas of thermal bridging.

Choosing an anchor which has very good thermal performance, but poor structural performance is likely to not only cost more but not provide the thermal benefit of having a similar performing thermal anchor which enable fewer connections to be used.

The Cassette® balcony system is considerably lighter in weight, (primarily because of its aluminium construction) and the anchors used are considerably stronger than other options available which both mean that the number of anchor connections required can be reduced, saving cost and minimising cold bridging.

An Introduction to StubGuard®

The move toward thinner slabs and minimal floor finishes has increased the incidence of details where there is insufficient form for the linear cavity barrier to pass under or over the interruption in the cavity barrier created by balcony support stubs.

Traditionally ad-hoc details have often been proposed requiring site assembling of fire stopping surrounds, but in many cases, these have not been subjected to testing, nor have adequate quality assurance measures been applied.

The Challenge:

As leading balcony suppliers, we have become aware the ‘post Grenfell’ industry urgently requires a tried and tested solution to this problem and have commissioned several fire tests evaluating the effectiveness of a range of possible solutions.

We have based these on the test regime for linear cavity seals BSEN 1366-4 and ASFP guidance document TGD17. The specimens were subjected to British Standard fire curve furnace temperatures rising to above 1000 0 C over 120 mins and continuously monitored for integrity along with temperature recording above the insulation as shown in the graph below.

The tests have indicated a solution which gives the required level of protection, and this has been selected for additional development, independent testing and certification.

The Solution

Whilst we are still working through the process of independent certification (which is expected to take several months) we are happy offer the Sapphire StubGuard® as an option on your project, subject to the approval of the fire engineer on the project.

Please contact us for further information.

Q – What is the lead time for the Sapphire StubGuard®?
A – Depending on quantity, normal lead times are around 8-10 weeks from point of order which matches our anchor sets. A phased delivery to site can also be accommodated. Please call to discuss if this lead time is a problem.

Q – What is the installation process for the Sapphire StubGuard®?
A – Sapphire would typically free issue these to the fire stopping contractor, who would install them onto the balcony bracket stubs just ahead of the main cavity barriers and fire stopping being installed to the facade. This will enable them to ensure complete continuity in the fire break.

Q – How are they designed?
A – Typically, the design will be produced by your allocated Sapphire contract manager and processed in conjunction with the progression of the arm and anchor design as dimensions vary from job to job and we will need to custom design your StubGuard® to suit your project anchor and stub or arm and connection plate sizes.

Q – Do I need to wait for third party certification before ordering the StubGuard®?
A – if your fire officer/specifier is happy with the results of the testing we have carried out at Exova Warringtonfire he can sign this off for you allowing you to proceed to order. We will be able to provide him with the necessary test results to confirm the suitability of the StubGuard® for use in your project.

Q – We are using a branded fire stopping solution right across our project. Is this compatible?
A – This product has been developed and tested alongside of proprietary cavity barriers from other premium suppliers to the industry with the excellent results shown in this document. However, please note that it needs to be the fire officers’ decision whether to incorporate StubGuard® into your scheme.

Q – How much do they cost?
A – Our sales team will happily give you a price for the project on application – or call us on – 0344 88 00 553. Typically, prices would be around £80-£110 per bracket depending on the cavity thickness, floor build up etc

Why Thermal Break?

Thermal or cold bridges occur where the insulation layer is penetrated by a material with a relatively high thermal conductivity...

Why Thermal Break

Achieving Thermal Efficiency

Firstly it is essential to always remember that thermal performance requirements need holistic consideration, not just individual component...

Achieving Thermal Efficiency on Balconies