Q&A Forums
Spray Foam Over Concrete Post New Topic | Post Reply
| Author | Comments |
|---|---|
|
John Thrash
Posted: Apr 23, 2008 12:19 PM
|
Spray Foam Over Concrete
What is the best procedure on spraying foam (2 1/2 lb) over concrete? It is refusing to stick for me. Thanks in advance
|
|
mason
Posted: Apr 23, 2008 01:40 PM
|
Fresh concrete frequently has contaminants on the surface, form oil, laitance, dirt, etc. You may need clean the concrete (powerwash) and spray an adhesive primer. In severe cases, it may require a sweep blast, then a primer. Ask your supplier for their recommendations. |
|
John Thrash
Posted: Apr 23, 2008 03:22 PM
|
Is it always a problem? The concrete has cured for over 90 days. Do you always need to use a primer to spray concrete/masonry block? |
|
Linerman
Posted: Apr 24, 2008 08:21 PM
|
In the coatings industry primer and a sealer must always be used, seal then prime after a shot blast and we have to do a moisture test to check levels of humidity before we can do anything to see if the job is doable. |
|
mason
Posted: Apr 25, 2008 08:41 AM
|
SPFA recommends priming concrete. If there are contaminants on the surface, the primer (as recommended by your foam supplier) may allow the foam to stick to the concrete, Even aged concrete can hold a lot of water that may not show up during a surface moisture meter probe, a primer may prevent moisture within the concrete from coming to the surface during the foam application. This can also affect adhesion. Following painting guidelines works pretty well for SPF. |
|
John Thrash
Posted: Apr 30, 2008 02:41 PM
|
Thanks Mason & Spray Pro. |
