Case study

Project:	Palmerston Hospital, Darwin, NT
Builder:	Lendlease
Architect:	MKEA Architects + dwp | suters
Application:	Roof System
Products:	Bradford PIR Boards Bradford Sarking

Palmerston Hospital Roof System Application

Project Overview

The $170M Palmerston Hospital project in Darwin is the first public hospital to be built in the Northern Territory for 40 years. The hospital is due to open in May 2018 and will deliver a state‑of-the-art facility accommodating 116 beds with provisions for future expansion.

Palmerston Hospital will employ 340 staff and deliver a range of services including 24/7 emergency department, maternity and child services, specialist support services and pathology.

Application Overview

The Palmerston Hospital roof system is designed for Darwin’s extreme tropical weather and has special engineering provisions to enable future expansion.

The roof system is made up of a metal roof structure that’s built on top of a concrete roof slab and incorporates two high performance insulation and condensation control layers.

The Bradford PIR Boards are installed on top of the concrete roof slab and the Bradford Sarking is installed directly under the metal roof sheets.

When it comes time to expand the hospital, the Bradford PIR Boards and metal roof structure can be easily removed and additional levels constructed on top of the concrete roof slab.

Roof System Performance

The roof system achieves a Total R-Value of R5.0 (heat flow down) and has condensation control layers at both roof and ceiling levels.

The concrete roof slab is insulated from above with Bradford PIR Boards. Each board was pinned and caulked to the slab with all joints taped.

The metal roof structure was insulated directly under the metal roof sheeting with Bradford Sarking. The sarking was rolled out over the safety mesh with joints overlapped, caulked and taped to twice seal the join.

Technical Project Support

The technical support from the Bradford team included thermal calculations, condensation risk evaluations, project specific installation instructions and on site product support.

Installation Methods

1 Bradford PIR Boards |  Xtratherm Xtroliner Duo 75mm

Bradford PIR Boards (Xtratherm Xtroliner Duo 75mm) was installed as a continuous insulation layer over the top of the concrete roof slab.

Each board was pinned and caulked to the slab with all joints and pin fixings taped.

2 Bradford Sarking |  Thermoseal 753 Heavy Duty

Bradford Sarking (Thermoseal 753 Heavy Duty) was installed directly under the metal roof – rolled out over the safety mesh in line with the purlins.

The roll side edge of the sarking was lapped by 150mm at the purlins and the joints were caulked using construction adhesive mastic. Foil tape was then placed on top to twice seal the join.