SMARTPLY ULTIMA OSB/4 key element in Irish commercial construction project

SMARTPLY ULTIMA OSB/4, manufactured by Irish wood panel producer MEDITE SMARTPLY, has been used to form part of a new specialist product specified for a major roofing project in Kilroot, Ireland.

The product, called WARMDEX®OSB, is a specialised insulated decking board for warm roof construction, designed to help conserve heat within the property without the need for ventilation.

It consists of insulated decking board made from Kingspan Kooltherm technology, with 22mm SMARTPLY ULTIMA OSB/4 boarding on the top layer. The core is manufactured with Kingspan’s high-performance CFC (Chlorofluorocarbons)/ HCFC (Hydrochlorofluorocarbons) -free, zero ODP (Ocean Depletion Potential) Resol foam technology, while the bottom layer comprises a low emission composite foil that is highly resistant to water vapour transmission.

Installed by expert zinc roofing contractors D.M. Specialist Roofing, the boards were fitted at the corporate office of a salt mine based in Kilroot, on the northern shore of Belfast Lough.

The installation also comprised a top skin of Rheinzink Blue Grey PRO-ROOF – a titanium zinc roof covering – supplied by ALMHM, a leading stockist and distributor of various hard metals for building facades and roofing, based in Ireland.

“We speak to a lot of architects, engineers and contractors and then we develop a system for a warm wall or warm roof application,” says Thomas Malone, National Roofing Manager for Kingspan Insulation Ltd. “With this product, we’ve eliminated the need for a cavity behind the wood panel. We put aluminium vapour barrier in the walls and roof and mechanically fix the insulation to whatever substrate there is.”

Unlike cold roofs, where insulation is fitted between the rafters, warm roof insulation is fitted on top of the existing surface.

Glen Doyle, General Manager at ALMHM, explains how it is installed: “A vapour control layer goes directly over on top up – usually an aluminium foil faced vapour barrier – then the bonded board is fixed over it and screwed back into the rafter. The board is bonded together using a special water-based PU adhesive, similar to our insulated slabs.

“The beauty of it is, because we have a top skin of OSB for all the fixings for the metal roof itself, the fixings don’t go through the insulation. They don’t have to go all the way to the substructure. The metal roof itself is held on to the board and the board is pinned down to the roof.”

SMARTPLY ULTIMA OSB/4 is suitable for the most demanding structural applications such as roofing in construction and offsite manufacturing. It also has higher moisture resistance and higher vapour resistance compared to OSB/3.

Glen continues: “We use SMARTPLY ULTIMA OSB/4 wood panels because they are manufactured using waterproof glues when the wood strands are bonded together, bringing a much higher level of moisture resistance and therefore greater reliability for the customer.”

This robust panel is manufactured using ContiRoll® technology, which sees wood strands precision orientated and continuously pressed to be able to achieve panels of up to 2.8m wide by 7.5m long, and to a maximum thickness of 40mm.

Finally, SMARTPLY ULTIMA OSB/4 panels are responsibly sourced from sustainably managed forests, which help contribute towards a building’s LEED and BREEAM sustainability credentials.

This project began in July 2019 and was completed in February 2020.