The Plaza at Longleat Forest in Wiltshire has just completed a 2 and half year Roof Refurbishment
Center Parcs Longleat Forest was originally opened in 1994 and is part of a European group of holiday complexes, founded in the Netherlands in 1968. The dome shaped canopy above the Plaza has been exposed to high levels of humidity over the last 22 years, especially the area above the Subtropical Swimming Paradise. This combined with external weathering and constant use had taken its toll on the structure.
The decision to refurbish the dome was approved by Center Parcs and following intensive planning work began in 2014. Top of the list of considerations with any project such as this is safety. Keeping disruption to a minimum was also a high priority. Up to 4000 guests are resident at Longleat Forest at any given time so keeping the Plaza open for business was very important.
About Longleat Forest
Situated in rolling countryside and woodland on the western edge of the county of Wiltshire, Longleat Forest is the largest and most popular of the 5 sites in the UK. Just a few miles from Frome and Warminster it is built on land adjacent to Longleat Safari Park. Although the site is owned and operated by Center Parcs UK the land, a total of 400 acres, is leased by the Marques of Bath to the holiday village.
The Plaza is the main building on the park which is where the mammoth roof coating took place. The dome shaped structure houses the Subtropical Swimming Paradise along with shops, restaurants and family entertainment facilities.
About the Roof Refurbishment Project
The project was awarded to Delomac Roofing, a Bedford based roofing contractor. They used Sika Sarnafil membrane for the primary work carried out on the Plaza dome. Planning began in 2012 before work commenced in 2014. It was a challenging project to undertake for all involved and required extensive planning and management, even before work started.
Even with regular maintenance and cleaning the dome glass had become stained and suffered from leakage in heavy downpours of rain. Tree sap had permanently left its mark along with extreme differences in temperature, especially during winter months. This had caused water-seal systems to perish over the years and maintenance crews were fighting a loosing battle trying to keep up with the leaks.
The Sika Sarnafil membrane and method of application by Delomac satisfied Center Parcs strict environmental and aesthetic needs. The systems ability to perform for many years into the future without failure and with much less maintenance was also a key requirement.
Maximum Safety with Minimum Disruption
In order to carry out the project with minimum disruption to the operations of the holiday village and with maximum safety for both workers and guests alike, a temporary stepped platform was designed and installed beneath the dome. It was suspended by cables and scaffold units to give workers access to the roof structure out of view of the guests below.
The temporary roof was fully weather proof and water-tight protecting the guests while they enjoyed the pool and restaurants below. The innovative structure shifted round during the course of the project in a balanced wheel effect, spreading weight evenly over 16 sections.
All the old glazing units and roof panels were then safely removed and the new components and membranes where installed. This took place while guests below were blissfully unaware of what was happening above them. The work spanned more than two years and took place during the wettest summers on record.
The Plaza and specifically the Subtropical Swimming Paradise, has a high level of humidity and high volume of chlorine saturated atmosphere. For this reason a robust SFS sealant and Sarnafil metal-lined vapour barrier was applied to the Glulam beams and fascias to prevent any condensation. Sarnafil membrane was then used for all coverings to create a permanent seal and weather proofing. A custom designed thicker membrane was produced by Sika in one single batch to ensure colour consistency and they visited the site 17 times to give advice and support to the teams.
Says Chris Meadows of Sika Sarnafil :
The client needed a durable, long-lasting roof system that would complement the woodland setting. This was complicated by differences between the swimming pool side and dry side, with restaurants and meeting rooms, of the building. We proposed two distinct solutions– a mechanically fastened system using Sarnafil S327-18EL for the dry side and an adhered system using Sarnafil G410-18EL for the more humid area. Both were specified in Patina Green to blend with the natural environment. Sarnafil membranes are cold applied and free from naked flames, the obvious choice for an open site.
Says Brendan McNulty of Delomac Roofing :
Installation methods and curved roof areas required our operatives to work from harness and rope access. We developed an innovative material loading trolley with the builder to deliver materials to the work sections safely, without compromising finishes. Workmanship standards remained exceptionally high, despite the challenging logistics, and met the client requirement of consistent lap and detail arrangement. This was also helped by the quality of the Sarnafil membranes. The finished installation has transformed the internal and external appearance of the building. Rooflights and white soffit finished decking have provided a bright and airy environment, with the external green finish blending subtly with the landscape. Most importantly, safe, unlimited guest access to the pool, restaurants and meeting areas was maintained throughout the entire project; something we’re very proud of.