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Glass 'Welcoming Pavilions' for Irish Government

The Department of the Taoiseach (Irish Prime Minister) in Dublin, Ireland turned to laminated safety glass for entrance checkpoints for the country's governmental headquarters.

The 40 m² pavilions, with their curved laminated glass walls and soft wood interiors, provide top protection for the police and military personnel guarding the Taoiseach while creating a welcoming, transparent and open atmosphere for government workers and visitors alike. They are positioned at the entrance of a large classical courtyard and feature on TV frequently as a backdrop to the reporting of Irish Governmental affairs.

The left hand security pavilion, which houses a soldier and a police officer, has walls of bullet-proof laminated glass. The right-hand pavilion houses officials that search everyone entering the complex using X-ray equipment.

Laminated glass walls protect police and military personnel while creating a welcoming, transparent and open atmosphere for government workers and visitors.

Merritt Bucholz of Dublin-based architects Bucholz McEvoy told LGN: "Irish Prime Minister Bertie Ahern and his team pass through the checkpoints frequently, as do all foreign dignitaries and states people. The latest security technology is employed as people pass through the pavilions yet the external appearance is very low key and friendly.

"It is critically important that the police and military personnel have excellent, clear degree vision on all three sides (about 270 degrees) in order to spot potential security threats. The laminated glass installations give them much better vision control than the traditional sentry boxes used in typical 'historic' government buildings, where a soldier can merely see straight ahead. For reasons of optical clarity, we wanted to avoid the use of very thick bullet-proof glass because visibility tends to go downhill as the glass construction gets thicker."

Bucholz McEvoy chose four-ply laminated glass (12 mm glass with 2.28 mm PVB interlayers) to achieve a European standard G3 bullet-proof rating for the cockpit where an armed soldier is on guard, with single layer laminated glass for the pavilion just opposite."

The glass was supplied by Roberglass of Calci, Italy, and the structural engineering firm for the project was RFR of Paris. RFR Director Tom Grey told LGN "At one point, polycarbonate was considered for this security application but as well as being a more expensive alternative, the material would not have provided the optical clarity we wanted. Optically-clear, laminated glass meets the specifications for this top security installation excellently."

Merritt Bucholz continued: "Long areas of floor-to-ceiling safety glass meant that it was essential to employ laminated safety glass. The laminated construction also helps to keep out street noise and prevent heat build-up inside the pavilions. For the optimal comfort of people inside the cockpits we also engineered a natural ventilation system involving 'floating roofs' where the welcoming agents can adjust the degree of cool air coming in from the outside via nozzles.

"A major design goal was to establish a harmonious aesthetic relationship with the Dublin Government buildings, which were constructed in the Beaux Arts style of the 1870s. The use of laminated glass enabled us to create a harmonious blend of old and new architecture.

"Finally, this project could not have been achieved without the excellent structural properties of laminated glass. The horizontal load cantilevers vertically and is supported at the top by a laminated glass beam, which consists of five separate pieces of 8 mm glass, each one 2.5 m long, which had to be pressed or bent first, then laminated (2 mm PVB interlayer) then toughened. The beam is secured with structural silicone at mitred corners with point fixings; this transfers the load from the vertical glass to the horizontal beam. The holes were drilled prior to chemical toughening. At the corners of the walls, the glass is curved vertically and horizontally. The achievement of manufacturing the curved glass this way is the optical quality remains excellent."