Waterproofing concrete roof

Introduction

Concrete roofs have a tendency to hold water and puddles form when it does not have a
proper runoff. When not protected with waterproofing water will enter the concrete slab and
mould will form. Newly laid concrete roofs must be waterproofed and the waterproofing
maintained. If not looking after, waterproofing systems will crack and lift off the slab. Now,
water underneath the waterproofing damages the slab and forms mould.     

Description

This concrete roof was left for too long without any proper maintenance. The waterproofing
system is failing as a result of the attack of Uv beams. It is cracked and starts to lift from the
slab leaving a pocket for water to accumulate. Mould is forming and some interior water
damage in the building is apparent. This is as a result of the deterioration of the old
waterproofing system. 

Old damaged waterproofing

Damaged waterproofing

Removing old waterproofing

Busy removing waterproofing

Old waterproofing removed

Possible outcome

Should the waterproofing not be removed and re-done the reinforcing inside the concrete will
start to corrode. This will weaken the roof structure and water seeping thru will cause internal
ceiling damage. The growth of mould will cause medical issues with occupants even
hospitalised. 

Suggestion

The recommendation in this case, as is in all concrete slab roofs, is to remove the damaged
waterproofing. Then the area should be cleaned of all dust and debris. A new waterproofing
system will only then be able to be installed.  

Decision with customer/owner 

An agreement was struck with the owner and the green light was given to proceed. 

Work commenced

Your step by applying the new waterproofing system is as follows.

Total removal of damaged waterproofing. Removal of dust and debris. The area is cleaned
with a high-power hose. Applying a new bonding agent on top of the concrete slab and the
new waterproofing system as per the manufacturer's specifications. A coat of paint will seal
the waterproofing, protecting it against UV beams.

Sail over the naked area for protection

Removing old waterproofing with new waterproofing attached in the background

Busy applying new waterproofing

Result 

After the application of the new waterproofing system, the building is leak-free. Small
maintenance needs to be done on the waterproofing every 5 years to ensure that it still
serves its purpose. 

Waterproofing in progress

Waterproofing process in progress

Application of waterproofing in progress

Waterproofing before painting

Finishing the painting process

Waterproofing painted as the final process

Finished waterproofing and painting

This waterproofing system offers a lifespan of approximately 20 years with a maintenance plan after every 5 years. Tremco offers a 5-year guarantee on all material and workmanship. An extended guarantee every 5 years is issued every 5years with the maintenance plan.