Laticrete for Capoterra City Hall roof repair

Situated to the south of the city of Cagliari, on the beautiful Italian island of Sardinia, lies the communal town of Capoterra, within view of the stunning waters of the Mediterranean Sea and along the foot of Mount Arcosu. Within the town of Capoterra, the notable public city hall now acts as a municipal archive for historic documents.

Built in the last century, the roof was adapted to hold vehicles for parking, as the location of the building within the crowded town meant that parking around the building was extremely difficult.

Over the years, the 1,200 square-meter roof had become in serious disrepair. The time had come to restore and support the roof, but also to provide a durable coating for the area that would last for years without the need for on-going work. The general contractor, Sardinian based Effe.Esse Costruzioni was asked to find a suitable product that could help protect the roof but be durable enough to cope with vehicle traffic over the coming decades.

As the building owners were the local municipal authority, it was vital that the job was done correctly the first time using the best materials. They also stipulated that the contractor only had a week to complete the work. Effe.Esse Costruzioni had used LATICRETE products on a previous project in Sardinia and knew exactly that LATICRETE Europe would specify the correct material for this difficult project.

The Challenge

The Capoterra City Hall is located within the busy streets of Capoterra. The building is in use six days of the week. To be without a parking area for weeks on end was not an option, but the work was vital to preserve the building’s roof for future generations.

There was also the work required to remove the existing material from the roof that was failing. This could potentially add days to the project schedule, so a solution that could be applied very quickly was required to compensate for days lost in the preparation work.

Once the existing material was removed, the roof would need a full repair of the cracks and joints, sealing, then a vapor barrier and waterproofing before a protective hard-wearing coating was applied to protect the system, and to cope with heavy motor vehicle traffic.

The Laticrete solution

After the first task of removing the existing, inadequate substrate was completed, the team of Effe.Esse Costruzioni under the guidance of LATICRETE Europe began to prepare the substrate for the LATICRETE system. It was important to remember, that although this was the parking area, it was also the roof of the City Hall and they had to protect the building and important documents below in the archives.

First, the cracks on the substrate were opened and any debris removed and cleaned from them. Then the cracks were properly repaired in order to receive the subsequent layers of product. They were sealed using a LATICRETE sealer. The metal structural supports also had to be opened, repaired and sealed during this process. Chosen for its vapor reduction protection and waterproofing qualities, three coats of a LATICRETE moisture vapor barrier together with fiberglass netting was used to protect the structural supports and to stop vapor emission.

A moisture vapor barrier is ideal for controlling moisture vapor emission and for waterproofing where there is an elevated slab involved. This product is also very quick drying and low in volatile organic compound (VOC) emissions. It is also ideal as a waterproofing product and can cope with both negative and positive hydrostatic pressure.

WTP TAPE (WATERPROOFING MEMBRANE) was applied over the metal supports using the two-part epoxy-polyurethane LATALASTIK adhesive, which is designed and perfect for adhesion to metal surfaces. WTP TAPE and LATALASTIK were also applied on and around the metal drains, which were on one side of the roof where the water drained away. 

Finally, to complete the preparation of the substrate, moisture vapor barrier was made perfectly smooth with a 150-grit sandpaper disc. The removal of the old substrate and the preparation of the new substrate took the team 5 days, using 5 applicators.

To complete the system, to protect the roof and provide a durable surface for motor vehicles, LATICRETE Europe recommended the polyaspartic resin coating GUARD PA SB, together with the GUARD PA SB PIGMENT BASE and a tile red POLYASPARTIC PIGMENT. GUARD PA SB is a clear, fast-curing two-part polyaspartic aliphatic polyurea sealer/finish coating used for both decorative and protective applications. Because of the ease of use and fast curing capabilities, it was the ideal choice as the final coating. Most importantly, the durability and strength of the coating would mean that the roof would have many years of protection and wear.

Two coats of the GUARD PA SB resin was used with the GUARD PA SB PIGMENT BASE and POLYASPARTIC PIGMENT, before a single final clear coat of GUARD PA SB was applied to complete the system. The project was completed within a week. A remarkable effort given the condition the roof was in at the start of the project. 

The Capoterra City Hall roof repair was completed within one week in March 2019, and the car parking area re-opened immediately. Effe.Esse Costruzioni together with the help of LATICRETE Europe, were able to preserve the historic building roof for future generations and to keep the roof functioning as a parking area using a quality system, and years of experience in construction solutions.