thermal insulataionThere are a very large number of buildings with reinforced concrete roof slabs which are not thermally insulated.  The top floor units and spaces below these roofs tend to be uncomfortably hot in the warmer months.  The initial developer construction of these buildings seldom includes thermal insulation.  
Richard Cortis can advise on the various means available to insulate many types of roof systems and terraces over habitable units below.

roof membranesThere are many types of flat roof construction.  All flat roofs depend upon some form of waterproofing system to exclude rainwater.  Some roofs use a sheet membrane system.  Others use a liquid applied membrane system.  Some concrete roofs (new construction) use concrete additives to attain waterproof integrity.  
Richard Cortis can advise on the various approaches to waterproofing in the many flat roof systems.

The majority of leakage into buildings is related to flashings and perimeter details.  In many cases, roof membranes, roof sheeting or roof tiles are replaced without rectifying the flashings at the perimeter of the roof which may be the major contributor to the rain water penetration into the building.  
Richard Cortis can investigate the cause of the rain water penetration and advise on the necessary extent of remedial work.

A skilled tradesman is required to effect neat and functional flashings in difficult locations.
Richard Cortis can assist in the design of difficult waterproofing details.


Many buildings constructed in the 1960's and 1970's were built with insufficient set-down or no set-down in the wall cavity. When flashings corrode and sealants harden and crack, water can penetrate during rainfall.Rectification often requires installation of a cavity bandage flashing or similar remedial waterproofing system. Richard Cortis can assist in identifying the defects and devising suitable remedial measures.

In complex and existing heritage buildings, specialist flashing and waterproofing works require the use of specialist tradesmen. The cost should be included in maintenance budgets

A simple flashing at a pipe penetration can reduce water penetration and dampness

Some simple flashing details can reduce water penetration


When drainage is neglected and ceases to function, pavements may become unserviceable