Viking Warm Roof. The most energy efficient roof insulation system

Transcription

1 Viking Warm Roof The most energy efficient roof insulation system

2 In 2007, the Department of Building and Housing introduced H1 the code requirement for building insulation; the aim of which was to decrease the amount of heating energy required by 30%, to achieve healthy indoor temperatures. Despite approximately 300,000 homes still being inadequately insulated, New Zealanders are looking increasingly closer at energy efficiency. There has never been a better time to invest in a warm roof What is a Warm Roof? The most commonly accepted definition of a warm roof (for low slope roofs) is a roof where the insulation is installed on top of the roof structure i.e. insulated from the outside of the building. The Viking Warm Roof includes rigid polyisocyanurate (closed-cell foam) sheets on top of which the waterproofing membrane is adhered. With a correctly designed warm roof: n The dew point is on the outside of the building = no damp or rotten materials inside n No ventilation of the ceiling cavity is required n Thermal bridging is avoided n The roof cavity is clear for wiring (not stuffed with insulation) n The savings in air conditioning and heating costs hugely shorten the amortisation period of the initial warm roof cost n The rigid insulation sheets add further structural integrity to the roof n Significantly higher R-values are achieved (uniformly across the entire roof; not just in parts) n Warm roof insulation systems can easily be retrofitted onto an existing building What components make up a Viking Warm Roof? n Thermal barrier (for cool stores and regions with extreme climatic variances) n Kingspan Polyiso insulation panel (including tapered and different facer types on indent) n Viking Epiclad or Enviroclad wide sheet membranes The Cold Roof Method Warm Roof In contrast to this technique, the mainstream method of insulating roofs in New Zealand is what s commonly referred to as the cold-roof method where the insulation (usually glass wool), is stuffed between rafters/joists in the ceiling cavity i.e. on the inside of the building. But there are a number of shortfalls with this system. With internal moisture levels in modern buildings higher than ever before, excess moisture rises up through gaps such as down-lights into the roof cavity. If the roof cavity is insufficiently vented, the moist air finds its dew point when it meets the underside of the roof substrate (the cold deck ). This condensation can lead to rotting roof substrates, damp ceilings and wet insulation (which eventually renders it ineffective). Even if the roof cavity is sufficiently vented a great deal of heat can be lost in the process. The maximum thickness of the wool insulation is restricted by the depth of the rafters/joists. Waterproofing Membrane 76mm Rigid Insulation Board Polyurethane Foam Adhesive Vapour Barrier Substrate Joists Ceiling Flush Downlight Clear Ceiling Cavity Roof Vent Waterproofing Membrane Substrate Traditional Insulation (eg Glass Wool) Joists Ceiling Cold Roof Flush Downlight

3 Why Viking Warm Roof? n Polyiso board supplied by Kingspan Insulation (World leading rigid insulation manufacturer) n F.A.S.T. adhesive option available to secure panels to substrate (Avoids mechanical fasteners and therefore some thermal bridging) n Wide sheet membrane = less seams Comprehensive Quality Assurance The Viking Warm Roof is backed by a 20 year warranty and is eligible to apply for the Viking Full System Warranty. n Craft paper facer can be torched to for torch-on membrane option** n Thermal performance of the system helps towards achieving green star points for a building n BRANZ appraised to ensure it meets New Zealand building code requirements n Full System Warranty option* = peace of mind n Tapered option = maximum watershed n Highest R-Value = maximum ROI n Rigid insulation sheets = dimensional stability n Highest possible fire performance rating (Group 1-S) = peace of mind n No CFCs in manufacture = environmentally friendly n Perfect as an overlay option = avoids re-roofing * Conditions apply ** Current Branz appraisal 713 applies to single ply membranes only. The intention is to update it to an all encompassing appraisal. The Building Code The Building Code is performance based, meaning the architect has the freedom to use any method of insulating a building provided the minimum R-value performance specified for the building s geographic zone will be met. If the building does not meet the minimum requirements for each of its categories (roof, walls, floor etc), calculation or modelling methods can be used where some well insulated areas can compensate for low insulation in others to achieve an acceptable aggregate R-value for the building. Due to its very high thermal efficiency, a Viking Warm Roof can assist in this way with architectural designs that have a disproportionate amount of glazing (thermally inefficient) to make the most of a view. For more information visit: Insulation Efficiency Comparison 1.25 Polyiso Spanning Capabilities on Metal Roofs Trough opening Min Thickness 76mm 100mm 30mm 176mm 200mm 50mm 276mm 300mm 70mm 1.00 R-Value per 25mm Skellerup Viking Polyiso Extruded Polystyrene Fibreglass Batts Batts Fibre Board Plywood Gypsum Paper Board Board Polyiso Physical Properties Property Compressive Strength 10% compression (BS EN 826) Water Vapour Resistance >300MN s/g-m (BS EN 12086) Fire Performance Rating Group 1-S (ISO9705)

4 The Overlay Option Thermal efficiency aside, a warm roof is a perfect, practical solution for overlaying over an existing lowslope roof with weather-tightness issues (of any substrate including metal). This is especially useful for buildings with inhabitants and/or expensive items and/or critical activities taking place inside, that would normally require re-locating if the existing roof had to be removed and fully replaced eg: supermarkets; schools; hospitals; manufacturing facilities. The Warm Roof option negates the need for relocation of people and contents and avoids the expensive waste disposal of the existing roof and scaffolding/shrink wrap covering required to maintain weather tightness during replacement. In the case of existing low-slope metal roofs, a warm roof overlay can avoid the expensive carpentry involved in re-pitching the roof plane up to the minimum 3 degree slope requirement. What s more, electricity savings from the building s new energy efficiencies can amortise the entire re-roof cost as quickly as 8 years after installation (depending on the thickness used and colour of membrane installed on top Refer to Supermarket Case study). Kingspan Insulation Represented in 70 countries (in 59 of which their insulation manufacturing facilities are located), Kingspan is one of the world s leading suppliers of panel-based insulation systems. With the provision of energy efficient systems as their reason-for-being, they are also leaders in the harnessing of solar and wind energy. More importantly, Kingspan Insulation has a sales office in Auckland, New Zealand, from where their NZ Manager (mostly on a technical capacity) works in partnership alongside Viking Roofspec to assist all project key stakeholders from the architect, builder and roofing contractor, through to the council and end-user in the appropriate specification and use of their worldclass products. For more information on Kingspan visit Kingspan Insulation R-Values Thickness Panel Dimensions R Value 25mm 1.2 x mm 1.2 x mm 1.2 x Tapered options and foil-faced options available on indent approx. 10 weeks lead time.

5 CaseStudy Controlling the Climate for Visitors and Plants - Christchurch Botanical Gardens Challenge The iconic Christchurch Botanical Gardens visitor centre has a complex roof - a 1000m2 saw tooth design with termination points featuring glass. As the self-proclaimed Garden City, it was important to create a comfortable environment for both the plants and the 1.4 million visitors per annum; particularly during the colder months. The new building was designed by award winning Auckland Architect Pattersons with design and installation of the roof taking 4 years from start to finish due to the interruption of earthquakes. Solution In an attempt to meet the comfort requirements Viking Roofspec recommended installation of a Warm Roof due to its ability to insulate the building and work into the design of the saw tooth roof. The Warm Roof system comprised of a white Enviroclad membrane at 1.5mm thick adhered over polyiso insulation panels of 76mm thickness, and a vapour barrier. The Enviroclad seams are always heat welded for the ultimate in waterproofing protection. White Enviroclad was used as it provides 92% solar reflectivity, (which provides numerous energy savings benefits). The R-Value (measure of thermal resistance) of the Warm Roof system is the highest in the construction industry and is pivotal to creating a comfortable internal environment throughout the seasons at the visitors centre. There were a number of challenges that came to Viking s attention during the project: Multiple redesigns from the glass manufacturers required changes to the roof design at the termination points Winter weather Substandard plywood had to be replaced before Viking could install their Warm Roof solution Coordination of contractor and sub-trades to deliver the project on time These were all challenges overcome by the architect, Viking and the Viking Approved Applicator, through a professional and focused approach utilising great teamwork and collaboration across the key stakeholders. It was all about taking care of the detail to ensure a watertight finish. Result With the Viking Warm Roof System installed, the Christchurch Botanical Gardens visitors centre was able to acquire a great looking roof incorporated into the overall aesthetics of the building, and more importantly achieve a watertight roof finish that protects the building and its inhabitants from the elements. Christchurch Botanical Gardens were also able to achieve the ultimate in quality assurance with the acquisition of a Viking Full System Warranty. This allows for greater risk minimisation as the warranty covers both the product and the installation under one process. Auckland Office 80 Alexander Crescent, Otara PO Box , Panmure Auckland 1741, New Zealand Christchurch Office 2 Nazareth Avenue, Middleton PO Box 9117, Tower Junction Christchurch 8149, New Zealand T F info@vikingroofspec.co.nz

6 CaseStudy Innovative Re-roof Solution - Countdown Supermarket, Napier Challenge The Countdown Supermarket in Carlyle Street, Napier, has a steel roof which had been bent and split due to foot traffi c. As a result the roof had been leaking into the supermarket. The building is owned by the Oyster Group, which is a specialist property company, operating throughout New Zealand. Solution In order to protect the building; Countdown s stock; and its customers, a new roof was required. Representatives from Viking Roofspec met with The Oyster Group to discuss three options: 1. Replacement with a heavier gauge steel roof 2. Replacing the roof with ply and membrane 3. Overlaying the steel with a Warm Roof System. Viking recommended the installation of the Viking Warm Roof. This is an overlay system where rigid sheets of polyurethane foam insulation called Polyiso, are installed on top of the steel. Polyiso renders the best R-value (energy-saving capacity per inch) of any insulation in the market. Viking Enviroclad membrane is then adhered on top to provide the waterproofi ng layer. The advantages of the Viking Warm Roof System are: Eliminating damage by foot track creating water ingress Adding structural integrity due to the adhered rigid insulation layer As the warm roof is an overlay system, the old roof didn t need to be removed. Otherwise there would have been costly downtime from evacuating the building during the re-roofi ng process No costs associated with disposing of the current steel roof (both labour and steel disposal costs). No need to uplift the existing air-conditioning and plant units Vital Energy Savings - The Warm Roof offers the benefi t of insulating the building during the changing New Zealand seasons. Extra insulation leads to vital energy savings. Additionally, the white Enviroclad membrane refl ects 92% of the sun s radiation, so during the hot Hawkes Bay summers, the refl ective roof will bring further energy savings The roof will deliver ongoing financial contributions to the building, eventually rendering itself as a free roof to The Oyster Group For peace of mind, Viking only has licenced applicators installing its materials which gives them the confi dence to provide a 20 year product warranty of substance. Result The Oyster Group purchased the Viking Warm Roof System to protect the building and offer security and peace of mind to its customer. It also provides the added benefi t of signifi cant energy savings which will eventually pay for the roof and contribute fi nancially to the building Auckland Office 80 Alexander Crescent, Otara PO Box , Panmure Auckland 1741, New Zealand Christchurch Office 2 Nazareth Avenue, Middleton PO Box 9117, Tower Junction Christchurch 8149, New Zealand T F info@vikingroofspec.co.nz