Hardware Designs for High Rise Facades

BES Technical Sharing -Issue 9 (July 20) Copyright@BEShttps://www.besconsultants.net

Mumbai News publish from “Mid-day” dt. June 20

Background

Generation demand for High rise buildings andhigh living luxury residentials developments hasdriven huge demand for new breed of buildingdevelopments and New designs often have noprecedents. We focus on residential high risebuildings which face unique challenges of manydifferent types of openings as per user demands.For the last 10 years or so, high rise developmentswith multi-functional requirements have posedgreat challenges. However the solutions foroperable have not been able to tackle the fast facedrequirements. This has resulted in less time tocreate new solutions and often designs usedsomewhere else are adopted.

Unfortunately we have been witnessing failures ofoperable in high rise which poses greater safetyrisks for both occupants and the public.

How is this done - ElsewhereMany parts of Asian countries enjoy comfortableweather for considerable period of the year.Hence large openings, natural ventilations are keyrequirements of building facades. Other regionsface extreme hot or Cold climates where inoperable may not be key design features. Forexample in European region, high riseresidentials generally have sealed envelopes withlimited operable or ventilated facades. Our regionrequires new design solutions, hence importeddesign solutions from other regions may not workunless local challenges are well thought of.

Lead to failure

Failure Analysis

Big difference in hardware strength, ie,.test condition Vs actual site condition.Hence we can’t just check weight capacity alone. Reliability is non linearlyreduced due to workmanship defects as explained in the graph

FailureAnalysis

Size & typeof Opening

Oversized - Not understandinghardware limitations

Hardware not upgraded

Wind effects -ignored

Safety compromiseddue to visual

Ease of operationsignored

Design

In appropriate

Light duty used at Extreme conditions

Mixed solutions -sold by Marketing

Hardware supplier-not aware of application

No secondary checks

No allowance for tolerances

Poor integration

Extrusions not compatiblewith hardware

Rely on packings for fixing

Hardware vendor notverified application

pick and choosefor cost cutting

Workmanship

Lack of skills

Site fixed -with parts missing

Fixings not robust

Mis aligned sashes

Sash fabricationsExceed tolerances

No protection-Site damaged

FailureAnalysis - 18/07/20- Mindjet

Hardware Designs for High Rise Facades

BES Technical Sharing -Issue 9 (July 20) Copyright@BEShttps://www.besconsultants.net

Local requirements, often very different

Requirements vary within regions, for example Singapore highrises(residential / commercial) do not require openings other than FireAccess Panels,. Whereas Indian building code (NBC) recommends10% facades to have operable for smoke and fire evacuation purposes.Hence these provisions on high rise buildings which experience highwind pressures need robust operable hardware solutions. Designingopenings in highrises requires good integration all the way fromdesign to implementation. Often sizes and design requirements arenot the same, hence every building requires skills and experiences tosafely design the operable with the right hardware.

I am using the best Internationalbrand -Why should I bother ?

Hardware is generally restricted to ahandful of international brands whichhave good track records. Howeverpremium brands do not guaranteetheir designs for local challenges. Justrelying on brand value alone may notbe adequate to take care of designsafety. We have witnessed severalfailures which have used premiumbranded hardware.

Unfortunately there is no one- stopsolution for façade integrated operable,for example a brand who makes handleand locks does not necessarily haverobust reliable stay arms. Thereforejust relying on a supplier team, withtheir commercial interest to sell theirown products may not be the bestsolution.

Due to these challenging requirements,pick and choose approach may workbetter with proper integration andassembly which may yield best ofeverything. However these requiredeeper involvement of façadedesigners, good experiences, deepintegration techniques, co-ordinations,etc,.

Comparison of typical Casement application

Typical Use Medium duty Heavy Duty

Std. sash with SGU/DGUglass, for low / medium ht.

Large sash with DGUglass, medium rise

Large sash with DGU glass,high rise

Just adding more light duty hinges in place of heavy duty hinges isNOT a safe solution. Heavy duty hinges have different fixing methodswhich reduces risk for challenging applications., Likewise whole rangeof components, not just a single component is to be given adequateattentions so that overall hardware system becomes reliable and safe.

Image : Sash failure due topoor fixing of stay arms

Typical Defects lead to failures such as hardware not integrated withextrusions, not engaged with Euro grooves, rattling of sashes due topoor fixings. Extrusions are some times not compatible for all types ofhardware, as a quick fix solution hardware is fixed with packing andshims which compromises safety.

Typical Defects

Hardware Designs for High Rise Facades

BES Technical Sharing -Issue 9 (July 20) Copyright@BEShttps://www.besconsultants.net

Prevention

Some key aspects are presented here as good design and implementationapproach.

Resolved design : Design and finalise hardware at thedesign stage, don’t leave it to fabrication stage. Sample of BESdrawing of pre-construction stage shows hardware details.

Skills and dedication are essential to avoid any failures.Wide Knowledge Not Limited to any brand, ratherfamiliar with availabilityDedicate Check in details, not to rely only based onsupplier’s dataTolerances Don’t just check weight capacity, considerimperfections and tolerances.Fabrication Knowledge Familiar with fabricationand fixing methods.Check and Verify Not just rely on drawings, test anddemonstrate at shop floor

Essential Skills

Hardware- Safe use

Type of opening

Choose as per functions

Residential

Commercial

Size of Opening

Mindful of size

Large sizes - cost more + safety risk

High rises - Limit the sizes - samesizes of low rise not essential

Impact of wind

Rattling due to poor fix

Rattling lead to fatigue failure

Smashing -heavywind

Safety

Allow restricted opening - use restrictor

Hinges or stay arms

Use appropriate size and numbers

Be aware of standard Vs Heavy duty type

Lock points engage while shut

Make it child safe

IntegrationWith facades

Extrusions to suit hardware

Avoid rely on packings for fixing

Careful with screws - use Pan Head

Local stiffening needed - min.Frame thickness use 2.5 mm

Capacity -not just weight of sashConsider tolerances

- Safe use - 19/07/20- Mindjet

Web version (with Videos) of thiswrite-up available here

Highrise facades hardware design