Comparing bridge waterproofing membranes: Not all liquid waterproofing is created equal

When it comes to waterproofing bridge decks, it’s easy to assume that all liquid waterproofing systems are the same. After all, they may look very similar on paper. However, there are key questions to ask when specifying liquid waterproofing to ensure you get a system that’s durable and can be applied quickly, to help keep the bridge project on track.  

How quickly can the waterproofing membrane be applied? 

Choosing a bridge waterproofing membrane that can be sprayed on fast and cures quickly is the first step. However, the real application time often comes down to what weather and temperature restrictions there are for applying the waterproofing system. Many liquid waterproofing systems are highly sensitive to moisture. 

Unfortunately, this means applicators have to wait around for the right weather conditions before they can apply the waterproofing. This puts added pressure on bridge owners, who may face complaints from the public the longer construction or lane closures go on. Choosing a waterproofing system that is less moisture sensitive helps avoid these delays. This can also be highly beneficial for contractors, who are often rewarded based on completion time.  

How do I ensure the waterproofing membrane is applied correctly?

Your waterproofing system is only as good as those who are applying it. Ask potential bridge deck waterproofing manufacturers if they have an approved contractor program and how their contractors are selected. Be sure to get references for projects that are similar to yours. 

It’s equally important to find out how and when quality control measures are taken. For example, spraying on the liquid waterproofing at the right thickness is essential to performance. Applying too thin a layer will compromise the physical performance of the membrane and applying too thick a layer may stress the bond of the paving.

Applicators using the ELIMINATOR® bridge deck membrane follow on-the-spot quality control measures, so they can quickly identify and resolve any issues. It is important to ensure you have the appropriate film thickness, measurable at the time of application. A two-coat system makes it easy to spray at the correct thickness. Pull testing, wet mil-thickness tests, holiday tests and bond tests are also performed throughout the application process.

How easy is it to repair the bridge deck waterproofing membrane?

Bridges are busy sites that have open exposure to a host of contaminants, not to mention multiple trades working together simultaneously. It’s best to choose a bridge deck waterproofing system that can be repaired on-the-spot if the membrane does get damaged. This helps keep the bridge construction on track. 

How do you test the performance of your waterproofing system?

In many regions, there are independent organizations, such as the British Board of Agrément, the Ministry of Transportation in Quebec, UBAtc in Belgium and CEREMA in France, who validate the performance characteristics of bridge deck waterproofing systems.

Can you demonstrate that your bridge deck waterproofing membrane stands up over the years?

Ask manufacturers both for references from long-term bridge projects as well as accelerated age testing data to see how the membranes have performed over the ensuing decades since they were applied. 

Learn about ELIMINATOR® bridge deck waterproofing.